U.S. patent application number 12/498785 was filed with the patent office on 2010-01-14 for paging and power management schemes for local network access.
This patent application is currently assigned to QUALCOMM Incorporated. Invention is credited to Parag A. Agashe, Rajarshi Gupta, Fatih Ulupinar.
Application Number | 20100008341 12/498785 |
Document ID | / |
Family ID | 41505068 |
Filed Date | 2010-01-14 |
United States Patent
Application |
20100008341 |
Kind Code |
A1 |
Ulupinar; Fatih ; et
al. |
January 14, 2010 |
PAGING AND POWER MANAGEMENT SCHEMES FOR LOCAL NETWORK ACCESS
Abstract
Paging and power consumption are managed in conjunction with
providing local breakout in a wireless wide area network. In some
aspects, if a packet destined for an access terminal is received at
an access point that provides local breakout, the access point may
inform the network so that the network will cause the access point
to page the access terminal. Alternatively, in some aspects an
access point that provides local breakout may maintain idle context
of the access terminal, whereby the access point may autonomously
page the access terminal (i.e., without involving the core
network). In some aspects local breakout traffic is filtered at an
access point to reduce the number of pages or packets sent to an
access terminal. In some aspects an indication of a packet type is
provided with a page message to enable an access terminal to
determine whether to receive the packet. In some aspects a local
link interface may be selectively disabled or enabled to limit
traffic at an access terminal.
Inventors: |
Ulupinar; Fatih; (San Diego,
CA) ; Agashe; Parag A.; (San Diego, CA) ;
Gupta; Rajarshi; (Santa Clara, CA) |
Correspondence
Address: |
QUALCOMM INCORPORATED
5775 MOREHOUSE DR.
SAN DIEGO
CA
92121
US
|
Assignee: |
QUALCOMM Incorporated
San Diego
CA
|
Family ID: |
41505068 |
Appl. No.: |
12/498785 |
Filed: |
July 7, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61079381 |
Jul 9, 2008 |
|
|
|
Current U.S.
Class: |
370/338 ;
455/458 |
Current CPC
Class: |
H04W 52/00 20130101;
H04W 68/00 20130101; H04W 84/027 20130101; H04W 68/02 20130101;
Y02D 30/70 20200801; H04W 52/0216 20130101 |
Class at
Publication: |
370/338 ;
455/458 |
International
Class: |
H04W 48/00 20090101
H04W048/00; H04W 68/00 20090101 H04W068/00 |
Claims
1. A method of communication, comprising: receiving a packet at an
access point via a local network, wherein the packet is destined
for an access terminal served by the access point; and paging the
access terminal only at the access point as a result of the receipt
of the packet.
2. The method of claim 1, wherein the paging further comprises:
sending a first message, as a result of the receipt of the packet,
to a network node that manages paging for the access terminal,
wherein the message comprises an indication that the access point
is to be paged; receiving a second message from the network node in
response to the first message, wherein the second message instructs
the access point to page the access terminal; and sending a page to
the access terminal based on the second message.
3. The method of claim 2, wherein the first message comprises an
indication that the access terminal is to be paged only at the
access point.
4. The method of claim 2, wherein the second message comprises at
least one of the group consisting of: a page identifier associated
with the access terminal and an indication of page timing for the
access terminal.
5. The method of claim 1, further comprising maintaining idle
context information for the access terminal at the access point,
wherein the paging further comprises sending a page to the access
terminal based on the idle context information.
6. The method of claim 5, wherein the paging is accomplished
without receiving a paging message from a network node that manages
paging for the access terminal.
7. The method of claim 5, wherein the idle context information
comprises at least one of the group consisting of: a page
identifier associated with the access terminal and an indication of
page timing for the access terminal.
8. The method of claim 5, further comprising acquiring the idle
context information by sending a request for the idle context
information to a network node that manages paging for the access
terminal.
9. The method of claim 8, further comprising receiving a
registration message from the access terminal, wherein the request
is sent in response to the registration message.
10. The method of claim 5, further comprising acquiring the idle
context information from a page request sent by a network node that
manages paging for the access terminal.
11. The method of claim 1, wherein the local network comprises: a
local area network to which the access point is connected; or an
internet connection that is not accessed via a cellular
network.
12. An apparatus for communication, comprising: a packet processor
configured to receive a packet at an access point via a local
network, wherein the packet is destined for an access terminal
served by the access point; and a paging controller configured to
page the access terminal only at the access point as a result of
the receipt of the packet.
13. The apparatus of claim 12, wherein the paging further
comprises: sending a first message, as a result of the receipt of
the packet, to a network node that manages paging for the access
terminal, wherein the message comprises an indication that the
access point is to be paged; receiving a second message from the
network node in response to the first message, wherein the second
message instructs the access point to page the access terminal; and
sending a page to the access terminal based on the second
message.
14. The apparatus of claim 12, wherein: the paging controller is
further configured to maintain idle context information for the
access terminal at the access point; and the paging further
comprises sending a page to the access terminal based on the idle
context information.
15. The apparatus of claim 14, wherein the paging controller is
further configured to acquire the idle context information by
sending a request for the idle context information to a network
node that manages paging for the access terminal.
16. The apparatus of claim 14, wherein the paging controller is
further configured to acquire the idle context information from a
page request sent by a network node that manages paging for the
access terminal.
17. An apparatus for communication, comprising: means for receiving
a packet at an access point via a local network, wherein the packet
is destined for an access terminal served by the access point; and
means for paging the access terminal only at the access point as a
result of the receipt of the packet.
18. The apparatus of claim 17, wherein the paging further
comprises: sending a first message, as a result of the receipt of
the packet, to a network node that manages paging for the access
terminal, wherein the message comprises an indication that the
access point is to be paged; receiving a second message from the
network node in response to the first message, wherein the second
message instructs the access point to page the access terminal; and
sending a page to the access terminal based on the second
message.
19. The apparatus of claim 17, further comprising means for
maintaining idle context information for the access terminal at the
access point, wherein the paging further comprises sending a page
to the access terminal based on the idle context information.
20. The apparatus of claim 19, further comprising means for
acquiring the idle context information by sending a request for the
idle context information to a network node that manages paging for
the access terminal.
21. The apparatus of claim 19, further comprising means for
acquiring the idle context information from a page request sent by
a network node that manages paging for the access terminal.
22. A computer-program product, comprising: computer-readable
medium comprising code for causing a computer to: receive a packet
at an access point via a local network, wherein the packet is
destined for an access terminal served by the access point; and
page the access terminal only at the access point as a result of
the receipt of the packet.
23. The computer-program product of claim 22, wherein the paging
further comprises: sending a first message, as a result of the
receipt of the packet, to a network node that manages paging for
the access terminal, wherein the message comprises an indication
that the access point is to be paged; receiving a second message
from the network node in response to the first message, wherein the
second message instructs the access point to page the access
terminal; and sending a page to the access terminal based on the
second message.
24. The computer-program product of claim 22, wherein: the
computer-readable medium further comprises code for causing the
computer to maintain idle context information for the access
terminal at the access point; and the paging further comprises
sending a page to the access terminal based on the idle context
information.
25. The computer-program product of claim 24, wherein the
computer-readable medium further comprises code for causing the
computer to acquire the idle context information by sending a
request for the idle context information to a network node that
manages paging for the access terminal.
26. The computer-program product of claim 24, wherein the
computer-readable medium further comprises code for causing the
computer to acquire the idle context information from a page
request sent by a network node that manages paging for the access
terminal.
27. A method of communication, comprising: receiving a first
message from an access point connected to a local network, wherein
the first message indicates that an access terminal served by the
access point is to be paged; and sending a second message to the
access point, wherein the second message instructs the access point
to page the access terminal.
28. The method of claim 27, wherein the first message comprises an
indication that the access terminal is to be paged due to the
access point receiving a packet on the local network that is
destined for the access terminal.
29. The method of claim 27, wherein the first message comprises an
indication that the access terminal is to be paged only at the
access point.
30. The method of claim 27, further comprising determining, based
on the first message, that the access terminal is to be paged only
at the access point.
31. The method of claim 27, wherein the second message comprises at
least one of the group consisting of: a page identifier associated
with the access terminal and an indication of page timing for the
access terminal.
32. The method of claim 27, wherein the local network comprises: a
local area network; or an internet connection that is not accessed
via a cellular network.
33. An apparatus for communication, comprising: a communication
controller configured to receive a first message from an access
point connected to a local network, wherein the first message
indicates that an access terminal served by the access point is to
be paged; and a paging controller configured to send a second
message to the access point, wherein the second message instructs
the access point to page the access terminal.
34. The apparatus of claim 33, wherein the first message comprises
an indication that the access terminal is to be paged due to the
access point receiving a packet on the local network that is
destined for the access terminal.
35. The apparatus of claim 33, wherein the first message comprises
an indication that the access terminal is to be paged only at the
access point.
36. An apparatus for communication, comprising: means for receiving
a first message from an access point connected to a local network,
wherein the first message indicates that an access terminal served
by the access point is to be paged; and means for sending a second
message to the access point, wherein the second message instructs
the access point to page the access terminal.
37. The apparatus of claim 36, wherein the first message comprises
an indication that the access terminal is to be paged due to the
access point receiving a packet on the local network that is
destined for the access terminal.
38. The apparatus of claim 36, wherein the first message comprises
an indication that the access terminal is to be paged only at the
access point.
39. A computer-program product, comprising: computer-readable
medium comprising code for causing a computer to: receive a first
message from an access point connected to a local network, wherein
the first message indicates that an access terminal served by the
access point is to be paged; and send a second message to the
access point, wherein the second message instructs the access point
to page the access terminal.
40. The computer-program product of claim 39, wherein the first
message comprises an indication that the access terminal is to be
paged due to the access point receiving a packet on the local
network that is destined for the access terminal.
41. The computer-program product of claim 39, wherein the first
message comprises an indication that the access terminal is to be
paged only at the access point.
42. A method of communication, comprising: receiving a packet at an
access point via a local network, wherein the packet is destined
for an access terminal served by the access point; determining a
packet type of the packet, wherein the packet type indicates
whether the packet is a non-unicast packet; and selectively
filtering the packet based on the determined type.
43. The method of claim 42, wherein the selective filtering
comprises electing to not page the access terminal as a result of
the receipt of the packet if the packet is a non-unicast
packet.
44. The method of claim 42, wherein the selective filtering
comprises electing to not deliver the packet to the access terminal
if the packet is a non-unicast packet.
45. The method of claim 42, wherein the determination comprises
determining whether the packet is a broadcast packet.
46. The method of claim 42, wherein the local network comprises: a
local area network to which the access point is connected; or an
internet connection that is not accessed via a cellular
network.
47. An apparatus for communication, comprising: a packet processor
configured to receive a packet at an access point via a local
network, and further configured to determine a packet type of the
packet, wherein the packet is destined for an access terminal
served by the access point and the packet type indicates whether
the packet is a non-unicast packet; and a packet filter configured
to selectively filter the packet based on the determined type.
48. The apparatus of claim 47, wherein the selective filtering
comprises electing to not page the access terminal as a result of
the receipt of the packet if the packet is a non-unicast
packet.
49. The apparatus of claim 47, wherein the selective filtering
comprises electing to not deliver the packet to the access terminal
if the packet is a non-unicast packet.
50. An apparatus for communication, comprising: means for receiving
a packet at an access point via a local network, wherein the packet
is destined for an access terminal served by the access point;
means for determining a packet type of the packet, wherein the
packet type indicates whether the packet is a non-unicast packet;
and means for selectively filtering the packet based on the
determined type.
51. The apparatus of claim 50, wherein the selective filtering
comprises electing to not page the access terminal as a result of
the receipt of the packet if the packet is a non-unicast
packet.
52. The apparatus of claim 50, wherein the selective filtering
comprises electing to not deliver the packet to the access terminal
if the packet is a non-unicast packet.
53. A computer-program product, comprising: computer-readable
medium comprising code for causing a computer to: receive a packet
at an access point via a local network, wherein the packet is
destined for an access terminal served by the access point;
determine a packet type of the packet, wherein the packet type
indicates whether the packet is a non-unicast packet; and
selectively filter the packet based on the determined type.
54. The computer-program product of claim 53, wherein the selective
filtering comprises electing to not page the access terminal as a
result of the receipt of the packet if the packet is a non-unicast
packet.
55. The computer-program product of claim 53, wherein the selective
filtering comprises electing to not deliver the packet to the
access terminal if the packet is a non-unicast packet.
56. A method of communication, comprising: determining, at an
access terminal, whether to access a service from a local network;
and selectively disabling a local link interface of the access
terminal based on the determination.
57. The method of claim 56, wherein the disabling of the local link
interface comprises releasing an Internet Protocol address
associated with the local link interface.
58. The method of claim 56, wherein the disabling of the local link
interface comprises turning off at least one component associated
with the local link interface.
59. The method of claim 56, wherein the determination is based on
whether the local link interface has been idle for a period of
time.
60. The method of claim 56, wherein the local link interface is
between the access terminal and a serving access point for the
access terminal that is connected to the local network.
61. The method of claim 56, wherein the local network comprises: a
local area network; or an internet connection that is not accessed
via the cellular network.
62. An apparatus for communication, comprising: a mode controller
configured to determine, at an access terminal, whether to access a
service from a local network; and a communication controller
configured to selectively disable a local link interface of the
access terminal based on the determination.
63. The apparatus of claim 62, wherein the disabling of the local
link interface comprises releasing an Internet Protocol address
associated with the local link interface.
64. The apparatus of claim 62, wherein the determination is based
on whether the local link interface has been idle for a period of
time.
65. An apparatus for communication, comprising: means for
determining, at an access terminal, whether to access a service
from a local network; and means for selectively disabling a local
link interface of the access terminal based on the
determination.
66. The apparatus of claim 65, wherein the disabling of the local
link interface comprises releasing an Internet Protocol address
associated with the local link interface.
67. The apparatus of claim 65, wherein the determination is based
on whether the local link interface has been idle for a period of
time.
68. A computer-program product, comprising: computer-readable
medium comprising code for causing a computer to: determine, at an
access terminal, whether to access a service from a local network;
and selectively disable a local link interface of the access
terminal based on the determination.
69. The computer-program product of claim 68, wherein the disabling
of the local link interface comprises releasing an Internet
Protocol address associated with the local link interface.
70. The computer-program product of claim 68, wherein the
determination is based on whether the local link interface has been
idle for a period of time.
Description
CLAIM OF PRIORITY
[0001] This application claims the benefit of and priority to
commonly owned U.S. Provisional Patent Application No. 61/079,381,
filed Jul. 9, 2008, and assigned Attorney Docket No. 081989P1, the
disclosure of which is hereby incorporated by reference herein.
CROSS-REFERENCE TO RELATED APPLICATION
[0002] This application is related to concurrently filed and
commonly owned U.S. patent application Ser. No. ______, entitled
"PAGING SCHEMES FOR LOCAL NETWORK ACCESS," and assigned Attorney
Docket No. 081989U2, the disclosure of which is hereby incorporated
by reference herein.
BACKGROUND
[0003] 1. Field
[0004] This application relates generally to wireless communication
and more specifically, but not exclusively, to facilitating
efficient local access.
[0005] 2. Introduction
[0006] Wireless communication systems are widely deployed to
provide various types of communication (e.g., voice, data,
multimedia services, etc.) to multiple users. As the demand for
high-rate and multimedia data services rapidly grows, there lies a
challenge to implement efficient and robust communication systems
with enhanced performance.
[0007] To supplement conventional mobile phone network base
stations, small-coverage base stations may be deployed (e.g.,
installed in a user's home) to provide more robust indoor wireless
coverage to mobile access terminals. Such small-coverage base
stations may be referred to as access point base stations, Home
eNodeBs ("HeNBs"), or home femtos. Typically, such small-coverage
base stations are connected to the Internet and the mobile
operator's network via a DSL router or a cable modem.
[0008] In some cases, one or more local services may be deployed at
the same location as a small-coverage base station. For example, a
user may have a home network that supports a local computer, a
local printer, a server, and other components. In such cases, it
may be desirable to provide access to these local services via the
small-coverage base station. For example, a user may wish to use
his or her cell phone to access a local printer when the user is at
home.
[0009] In general, an Internet-enabled access terminal may not be
able to communicate with a device on a home network because this
device is protected by a firewall and the network address
translation ("NAT") within the home router and the access terminal
appears as a node on the public Internet from the perspective of
the home network. There are methods to enable limited access to
some home devices by using port forwarding, however, this requires
detailed technical knowledge about the devices, the associated
applications and the home router equipment, which may be considered
beyond the capabilities of a wireless access terminal user.
Accordingly, a need exists for efficient and effective methods for
accessing local services.
SUMMARY
[0010] A summary of sample aspects of the disclosure follows. It
should be understood that any reference to the term aspects herein
may refer to one or more aspects of the disclosure.
[0011] The disclosure relates in some aspects to managing paging
and power consumption in conjunction with providing access to local
services in a wireless wide area network. For example, an access
terminal that is deployed in a mobile network (e.g., a cellular
network) may access such a local service when the access terminal
is being served by an access point (e.g., a HeNB) that provides
local network access (also known as local breakout).
[0012] The disclosure relates in some aspects to enabling an access
terminal to be paged if a local breakout packet destined for the
access terminal is received at an access point. In some
implementations, upon receipt of such a packet, the access point
informs a network paging management entity (e.g., of the core
operator network) so that this entity will cause the access point
to page the access terminal. Alternatively, in some implementations
the access point may maintain idle context of the access terminal,
whereby the access point may autonomously page the access terminal
(i.e., without involving a network paging management entity). In
this way, the network may be relieved of paging-related operations
for local breakout.
[0013] The disclosure relates in some aspects to filtering local
breakout traffic to reduce the number of pages or packets sent to
an access terminal. In some implementations an access point that
provides local breakout for an access terminal may filter certain
local breakout packets destined for the access terminal. For
example, upon receipt of a non-unicast packet, the access point may
not page that access terminal (if the access terminal is in idle
mode) or the access point may not deliver the packet to that access
terminal (if the access terminal is in active mode). In some
implementations, an access point that provides local breakout may
selectively filter local breakout packets destined for the access
terminal based on the current operating mode of the access
terminal. For example, an election may be made at the access
terminal (e.g., by a user or an application) as to whether
non-unicast packet are to be delivered to the access terminal,
whereupon an indication of this election (e.g., the current
operating mode of the access terminal) is sent to the access
point.
[0014] The disclosure relates in some aspect to providing an
indication of a packet type when paging an access terminal to
enable the access terminal to decide whether to receive the packet.
Here, upon receipt of a local breakout packet destined for the
access terminal, the access point determines a type of the packet
and includes an indication of this type when paging the access
terminal. Upon receipt of this page, the access terminal may decide
whether to receive this packet (e.g., decide whether to switch to
active mode and contact the access point to receive the
packet).
[0015] The disclosure relates in some aspect to reducing traffic
load associated with local breakout by selectively disabling or
enabling a local link interface. For example, the link interface
may be temporarily disabled if the local link has been idle for a
defined period of time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] These and other sample aspects of the disclosure will be
described in the detailed description and the appended claims that
follow, and in the accompanying drawings, wherein:
[0017] FIG. 1 is a simplified block diagram of several sample
aspects of a communication system where paging and power
consumption are managed in conjunction with providing local
breakout;
[0018] FIG. 2 is a flowchart of several sample aspects of
operations that may be performed to manage paging and power
consumption in conjunction with providing local breakout;
[0019] FIG. 3 is a simplified block diagram of several sample
aspects of components that may be employed in communication nodes
in conjunction with providing local breakout;
[0020] FIG. 4 is a flowchart of several sample aspects of
operations that may be performed in conjunction with paging an
access terminal via a network in response to receipt of a local
breakout packet;
[0021] FIG. 5 is a flowchart of several sample aspects of
operations that may be performed in conjunction with autonomous
paging of an access terminal by an access point in response to
receipt of a local breakout packet;
[0022] FIG. 6 is a flowchart of several sample aspects of
operations that may be performed in conjunction with filtering
local breakout packets destined for an access terminal;
[0023] FIG. 7 is a flowchart of several sample aspects of
operations that may be performed in conjunction with selectively
filtering local breakout packets destined for an access terminal
based on an operating mode of the access terminal;
[0024] FIG. 8 is a flowchart of several sample aspects of
operations that may be performed in conjunction with sending an
indication of a received local breakout packet type when paging the
destination access terminal to enable the access terminal to decide
whether to receive the packet;
[0025] FIG. 9 is a flowchart of several sample aspects of
operations that may be performed in conjunction with disabling a
local link;
[0026] FIG. 10 is a simplified diagram of a wireless communication
system;
[0027] FIG. 11 is a simplified diagram of a wireless communication
system including femto nodes;
[0028] FIG. 12 is a simplified diagram illustrating coverage areas
for wireless communication;
[0029] FIG. 13 is a simplified block diagram of several sample
aspects of communication components; and
[0030] FIGS. 14-21 are simplified block diagrams of several sample
aspects of apparatuses configured to provide local breakout
operations as taught herein.
[0031] In accordance with common practice the various features
illustrated in the drawings may not be drawn to scale. Accordingly,
the dimensions of the various features may be arbitrarily expanded
or reduced for clarity. In addition, some of the drawings may be
simplified for clarity. Thus, the drawings may not depict all of
the components of a given apparatus (e.g., device) or method.
Finally, like reference numerals may be used to denote like
features throughout the specification and figures.
DETAILED DESCRIPTION
[0032] Various aspects of the disclosure are described below. It
should be apparent that the teachings herein may be embodied in a
wide variety of forms and that any specific structure, function, or
both being disclosed herein is merely representative. Based on the
teachings herein one skilled in the art should appreciate that an
aspect disclosed herein may be implemented independently of any
other aspects and that two or more of these aspects may be combined
in various ways. For example, an apparatus may be implemented or a
method may be practiced using any number of the aspects set forth
herein. In addition, such an apparatus may be implemented or such a
method may be practiced using other structure, functionality, or
structure and functionality in addition to or other than one or
more of the aspects set forth herein. Furthermore, an aspect may
comprise at least one element of a claim.
[0033] FIG. 1 illustrates several nodes of a sample communication
system 100 (e.g., a portion of a wireless wide area network). For
illustration purposes, various aspects of the disclosure will be
described in the context of one or more access terminals, access
points, and network nodes that communicate with one another. It
should be appreciated, however, that the teachings herein may be
applicable to other types of apparatuses or other similar
apparatuses that are referenced using other terminology. For
example, in various implementations access points may be referred
to or implemented as base stations, eNodeBs, or HeNBs, while access
terminals may be referred to or implemented as user equipment or
mobile stations, and so on.
[0034] Access points in the system 100 provide one or more services
(e.g., network connectivity) for one or more wireless access
terminals that may be installed within or that may roam throughout
the coverage area of the access points. For example, at various
points in time an access terminal 102 may connect to an access
point 104. To reduce the complexity of FIG. 1, only a single access
point 102 and a single access terminal 104 are shown.
[0035] Each of the access points in the system 100 may communicate
with one or more network nodes (represented, for convenience, by
network node 106) to facilitate wide area network connectivity. A
network node may take various forms such as, for example, one or
more core network entities (e.g., an operation, administration, and
maintenance server, a mobility management entity, or some other
suitable network entity).
[0036] The nodes in the system 100 may employ various means to
communicate with one another. In the example of FIG. 1, the access
point 104 may connect to a router 108 as represented by a
communication link 110, the router 108 may connect to the Internet
112 as represented by a communication link 114, and the network
node 106 may connect to the Internet 112 as represented by a
communication link 116. In addition, the access terminal 102
communicates with the access point 104 via an air interface link
118 (as represented by the RF symbol).
[0037] Through the use of these communication links, the access
terminal 104 may communicate with various correspondent nodes
(e.g., nodes 120, 122, and 124) in the system 100. In some aspects,
access to these different correspondent nodes may be referred to
herein as involving network access or local breakout access.
[0038] For example, network access relates in some aspects to a
service accessed via an operator's core network (e.g., the core
network of a cellular network). That is, an access terminal may
access network services in a similar manner as when the access
terminal is connected to a macro network (e.g., connected to a
macro base station of a wireless operator's network). In the
example of FIG. 1, access to the correspondent node 120 (e.g.,
another access terminal) may thus be defined as a network
(non-local) service since this node is accessed via the operator's
core network 126. Traffic flow between the access terminal 102 and
the correspondent node 120 (e.g., via links 118, 110, 114, and 116)
is represented by dotted line 128. Typically, this traffic is
routed between the access point 104 and the operator's core network
126 (e.g., an IP gateway for the access terminal 102 in the core
network 126) via a protocol tunnel (e.g., an IPsec tunnel) as
represented by a pair of lines 130.
[0039] Local breakout access relates in some aspects to accessing a
local service without going through an operator's core network. For
example, an access terminal may access certain services when the
access terminal is at a home network or some other local network.
Advantageously, by bypassing the operator's core network, latency
(e.g., response times for an access terminal) may be improved and
resources on the operator network may be conserved (e.g., by
off-loading traffic from the operator's core network).
[0040] Local service may take various forms. In some
implementations local service may relate to services provided by
entities on a local network. For example, the correspondent node
124 may represent a device that resides on the same IP subnetwork
as the access point 104 (e.g., a local area network served by the
router 108). In this case, accessing a local network service may
involve accessing a local printer, a local server, a local
computer, another access terminal, or some other entity on the IP
subnetwork. In FIG. 1, traffic (e.g., packet) flow between the
access terminal 102 and the correspondent node 124 is represented
by dashed line 132. The line 132 illustrates that the access
terminal 102 may access this local service via the access point 104
and the router 108 (i.e., via links 118 and 110) without going
through the operator's core network 126.
[0041] In some implementations a local service may relate to a node
that is connected to some other network (e.g., correspondent node
122 connected to the Internet 112). For example, the router 108 may
provide an Internet connection to an Internet service provider
("ISP") and the access terminal 102 may use this Internet
connection to access service provided by the node 122 (e.g., a web
server). Accordingly, through the use of local IP access, different
access terminals in a network may be provided with Internet access
at certain locations (e.g., a user's home, an employer's facility,
an Internet hotspot, etc.) without accessing the wireless
operator's core network. Traffic flow between the access terminal
102 and the correspondent node 122 (e.g., via links 118, 110, and
114) is represented by dashed line 134 in FIG. 1.
[0042] The use of local breakout raises several issues which may
affect system performance. First, an access terminal may need to be
paged to deliver packets that do not arrive via the operator's core
network. However, conventional operator networks are designed to
handle paging at the core network (e.g., the idle context for
paging the access terminal is maintained within the core network).
Second, there may be a significant number of messages associated
with local traffic. Thus, the battery life of an access terminal
may be significantly reduced if the access terminal needs to wake
from idle mode to process these messages. However, access terminals
are typically wireless battery operated devices that are expected
by the users to have a long battery life when left idle.
[0043] With respect to managing paging, in a typical wireless
network (e.g., 1xEvDO, UMB, UMTS, HSPA, LTE, WiMAX), an access
terminal is paged only to send a packet flowing through the
operator's core network. This allows the operator to consolidate
paging functionality of the access terminal in a core network
element (e.g., a mobility management entity, MME, in LTE). This
core network element is the only entity which keeps detailed
information on how and when to page an access terminal, as access
terminals maintain a strict sleep (i.e., idle mode) regime to
extend their battery life. In addition, to further conserve the
battery of the access terminal, the access terminal may only be
required to register with the core network after passing through
the coverage area of several access points (e.g., eNBs)
constituting a paging area (e.g., a zone, a tracking area, etc.).
To accommodate this registration scheme, the access terminal may be
paged by all of the access points in the paging area.
[0044] However, with local breakout, the access terminal may need
to be paged to deliver packets that do not flow through the
wireless operator's core network. Rather these packets may arrive
at a particular access point (e.g., HeNB) that is connected to the
corresponding local network. Moreover, when an access terminal is
to be paged to deliver a packet arriving through a local breakout
interface, it may be desirable to only page the access terminal at
the access point that provides the local breakout, irrespective of
the current paging area of the access terminal.
[0045] With respect to managing power consumption, conventional
operator controlled wireless networks are set up such that only the
traffic the access terminal is interested in is sent to the access
terminal. In contrast, typical local networks (e.g., home networks)
may utilize various protocols that send a large number of broadcast
messages. These protocols include, for example, address resolution
protocol ("ARP") for finding the media access control ("MAC")
address of the nodes on the local network; universal plug-and-play
("UPnP") packets for service advertisement, discovery and
configuration; server message block ("SMB") packets for windows
networking; and specific device beacons (e.g., TIVO.RTM. DVR
beacons).
[0046] Under normal network operation, the packets generated by
such protocols shall be delivered to all nodes in the local network
as they are sent using a broadcast IP address. However, there may
be thousands of such packets in a typical network during a 24 hour
period. As a result, with local breakout, an access terminal could
be paged thousands of times during the day, thereby draining the
battery of the access terminal much faster than normal (e.g., when
the access terminal is served by a macro network).
[0047] FIG. 2 provides an overview of paging and power management
operations that may be employed to address these and other issues.
For convenience, the operations of FIG. 2 (or any other operations
discussed or taught herein) may be described as being performed by
specific components (e.g., components of the system 100). It should
be appreciated, however, that these operations may be performed by
other types of components and may be performed using a different
number of components. It also should be appreciated that one or
more of the operations described herein may not be employed in a
given implementation.
[0048] As represented by block 202, at some point in time a packet
destined for the access terminal 102 (FIG. 1) arrives at the access
point 104 via a local network. For example, the packet may
originate at or be relayed by the correspondent node 124 or the
correspondent node 122.
[0049] As represented by block 204, the access point 104 determines
whether and/or how to page the access terminal 102 based on the
particular paging and/or power management scheme implemented by the
access point 104 and/or the access terminal 102. In accordance with
the teachings herein, in some aspects these schemes may limit
paging and/or packet traffic directed to the access terminal 102.
For example, as discussed in more detail below in conjunction with
FIGS. 6 and 7, in some implementations the access point 104 (e.g.,
by operation of a packet filter 136) filters local breakout traffic
to reduce the number of pages or packets sent to the access
terminal 102. Here, the filtering may be accomplished in a static
manner (e.g., as described at FIG. 6) or in a dynamic manner based
on an operating mode of the access terminal (e.g., as described at
FIG. 7). In the latter case, the access terminal 102 (e.g., a
filter mode controller 138) sends an indication of a current
operational mode of the access terminal 102 to the access point 104
to enable the access point 104 (e.g., a filter mode controller 140)
to control the packet filtering operation accordingly. As discussed
in more detail below in conjunction with FIG. 8, in some
implementations the access point 104 (e.g., a local breakout paging
controller 142) sends an indication of a packet type while paging
the access terminal 102, whereby the access terminal 102 determines
whether to receive the packet based on the indication. As discussed
in more detail below in conjunction with FIG. 9, in some
implementations the access terminal 102 (e.g., a link interface
controller 144) selectively disables a local link interface to
limit traffic at the access terminal 102.
[0050] As represented by block 206 of FIG. 2, in the event the
access terminal 102 is to be paged (e.g., a received local breakout
packet is not filtered), the access point 104 (e.g., the local
breakout paging controller 142) initiates operations to cause the
access terminal 102 to be paged. In some cases the access terminal
102 is only paged at the access point 104. In some cases the access
terminal may be paged at some other reduced set of access points
(e.g., reduced as compared to the set of access points that provide
the current operator network paging area of the access terminal
102).
[0051] As discussed in more detail below in conjunction with FIG.
4, in some implementations the access point 104 (e.g., the local
breakout paging controller 142) sends a request to the core network
entity responsible for idle mode operations of the access terminal
102 to cause that entity to invoke a page of the access terminal
102. In the example of FIG. 1, this entity is represented in some
aspects by the network node 106 which may include paging controller
functionality (e.g., an MME). In some cases the request from the
access point 104 may include an indication for the access terminal
102 to be paged only at the access point 104 (or at some other
reduced set of access points). Alternatively, in other cases the
core network entity may determine that the access terminal 102 is
to be paged only at one of these reduced access point sets (e.g.,
based on receipt of the request from the access point 104). Here,
paging at any other access points may be unnecessary since the
access terminal 102 needs to be in the coverage area of the access
point 104 to receive the local breakout packet. Consequently, it is
highly likely that the access terminal 102 will hear the page from
the access point 104.
[0052] As discussed in more detail below in conjunction with FIG.
5, in some implementations the access point 104 (e.g., the local
breakout paging controller 142) autonomously pages the access
terminal, without contacting the core network entity responsible
for idle mode of the access terminal 102. Here, the access point
104 may acquire (e.g., retrieve) and store a copy of the idle
context of the access terminal. Then, when a packet is received on
the local breakout, the access point 104 pages the access terminal
directly.
[0053] With the above overview in mind, additional details relating
to providing paging and power management in accordance with the
teachings herein will be described with reference to FIGS. 3-9.
FIG. 3 illustrates several components that may be employed in
communication nodes. The flowcharts of FIGS. 4 and 5 relate to
various paging techniques. The flowcharts of FIGS. 6-9 relate to
various power management techniques.
[0054] For purposes of illustration, FIG. 3 depicts sample
components incorporated into the access terminal 102, the access
point 104, and the network node 106 to perform paging and/or power
management as taught herein. The described components also may be
incorporated into other nodes in a communication system. For
example, other nodes in a system may include components similar to
those described for the access terminal 102, the access point 104,
and the network node 106 to provide similar functionality. In
addition, a given node may contain one or more of the described
components.
[0055] As shown in FIG. 3, the access terminal 102, the access
point 104, and the network node 106 may each include at least one
transceiver block 302, 304, and 306 respectively, for communicating
with other nodes. The transceiver block 302 depicts a transmitter
308 for sending signals and a receiver 310 for receiving signals.
For example, the access terminal 102 may send messages such as mode
indications to the access point 104 and receive pages, beacons,
packets, and various other messages from the access point 104. The
transceiver block 304 depicts a transmitter 312 for sending signals
and a receiver 314 for receiving signals. For example, the access
point 104 may transmit pages, beacons, packets, and various
messages to the access terminal 102 and receive messages such as
mode indications from the access terminal 102. In addition, the
access point 104 may send messages such as requests to the network
node 106 and receive page requests, idle context information, and
network packets from the network node 106. The transceiver block
306 depicts a transmitter 316 for sending signals and a receiver
318 for receiving signals. For example, the network node 106 may
send page requests, idle context information, and network packets
to the access point 104 and receive messages such as requests from
the access point 104.
[0056] Depending on the connectivity of the nodes of FIG. 3, the
transceiver blocks of FIG. 3 may support different communication
technologies. For example, a transceiver block may represent one or
more transceivers that enable communication via a wired link and/or
a wireless link. For example, communication between the access
terminal 102 and the access point 104 is accomplished using
wireless communication technology. In addition, in some cases
communication (e.g., backhaul communication) between the network
node 106 and the access point 104 is accomplished using wired
communication technology. In other cases wireless technology may be
employed here (e.g., where an access point accesses the network via
a wireless relay).
[0057] The access terminal 102, the access point 104, and the
network node 106 also include other components that may be used in
conjunction with paging and/or power management as taught herein.
For example, the access terminal 102, the access point 104, and the
network node 106 may include communication controllers 320, 322,
and 324, respectively, for managing communication with other nodes
(e.g., establishing communication interfaces, sending and receiving
messages/indications) and for providing other related functionality
as taught herein. In addition, the access terminal 102, the access
point 104, and the network node 106 may include a paging controller
326, a paging controller 328 (e.g., corresponding to controller 142
in FIG. 1), and a paging controller 330, respectively, for
performing paging-related operations (e.g., receiving or sending
pages or sending or receiving page-related requests) and for
providing other related functionality as taught herein. The access
terminal 102 and the access point 104 may include packet processors
332 and 334, respectively, for processing (e.g., sending and
receiving) packets and for providing other related functionality as
taught herein. The access terminal 102 and the access point 104 may
include a mode controller 336 (e.g., corresponding to controller
138) and a mode controller 338 (e.g., corresponding to controller
140), respectively, for performing access terminal operating
mode-related operations (e.g., generating an indication of the mode
or determining the mode) and for providing other related
functionality as taught herein. The access point 104 also may
include a packet filter 340 (e.g., corresponding to filter 136) for
filtering packets (e.g., determining whether to page the access
terminal or deliver a packet to the access terminal) and for
providing other related functionality as taught herein.
[0058] For convenience the access terminal 102, the access point
104, and the network node 106 are shown in FIG. 3 as including
components that may be used in the various examples described below
in conjunction with FIGS. 4-9. In practice, one or more of the
illustrated components may not be used in a given example. As an
example, in some implementations the access terminal 102 may not
include the mode controller 336. Also, in some implementations the
access point 104 may not include one or more of the packet filter
340 or the mode controller 33 8.
[0059] Furthermore, different operations may be performed by an
illustrated component in different implementations. As an example,
in some implementations the paging controller 328 may perform
operations such as those described in FIG. 4 while in other
implementations the paging controller 328 may perform operations
such as those described in FIG. 5.
[0060] Referring now to FIG. 4, operations relating to a sample
implementation where a network node manages local breakout paging
will be described in more detail. As mentioned above, in this
example, the access point 104 informs the network node 106 that a
local breakout packet destined for the access terminal 102 has been
received, whereupon the network node sends a message to cause the
access point 104 to page the access terminal 102.
[0061] As represented by block 402, at some point in time the
access point 104 (e.g., the packet processor 334, FIG. 3) receives
a local breakout packet destined for the access terminal 102. As
discussed herein, this packet may be received via a local breakout
(e.g., from correspondent node 124 or 122) provided by the access
point 104.
[0062] As represented by block 404, in response to the receipt of
the packet at block 402, the access point 104 (e.g., the paging
controller 328) sends a message to the network node 106 (e.g., an
MME), wherein the message indicates (e.g., requests) that the
access terminal 102 is to be paged. This message may take various
forms. For example, in some cases the message includes an
indication that a local breakout packet has been received.
[0063] In some cases the message includes an indication that a
reduced access point set should be used to page the access
terminal. Such an indication may comprise, for example, an
identifier of the access point 104, an identifier of several access
points (e.g., a set of neighboring access points), or an indication
that a local breakout packet has been received.
[0064] The network node 106 receives this message as represented by
block 406. For example, this message may be processed by the
communication controller 324 depicted in FIG. 3.
[0065] As represented by block 408, the network node 106 (e.g., the
paging controller 330) determines where to page the access terminal
102. For example, the network node 106 may determine that the
access terminal 102 is to be paged at a reduced access point set.
This determination may be based on an indication received in
conjunction with the message from the access point 104 or based on
other information available to the network node 106. As examples of
the latter case, the network node 106 may determine that a reduced
access point set is to be used: based on the packet being a local
breakout packet; based on the message being sent from an access
point that provides local breakout; based on the message being sent
by an access point; or based on some on some other criterion or
criteria.
[0066] As represented by block 410, in response to the message
received at block 406, the network node 106 (e.g., the paging
controller 330) sends a message to the access point 104 to instruct
the access point 104 to page the access terminal 102. For example,
the message may comprise a page request that includes a page
identifier (e.g., an identifier assigned to the access terminal for
paging) and page timing information (e.g., an indication of a
paging interval and/or a paging offset).
[0067] The access point 104 receives this message as represented by
block 412. As represented by block 414, the access point 104 (e.g.,
the paging controller 328) then pages the access terminal 102 in
response to the receipt of this message.
[0068] Referring to FIG. 5, operations relating to a sample
implementation where an access point autonomously manages local
breakout paging will be described in more detail. In this example,
the access point 104 does not send a message to the network node
106 to invoke paging of the access terminal 102.
[0069] As represented by block 502, at some point in time the
access terminal 102 connects to the access point 104. For example,
in an implementation where the access point 104 is a HeNB, the
access terminal 102 may register with the access point 104 when the
user of the access terminal 102 is at home. Once this connection is
made, the access point 104 may become the serving access point for
the access terminal 102.
[0070] As represented by block 504, the access point 104 (e.g., the
paging controller 328) acquires the idle context of the access
terminal 102. This may be accomplished in various ways. For
example, in some implementations the access point 104 sends a
request to the network (e.g., network node 106) or to some other
node for the idle context. In some implementations the access point
104 acquires the idle context from a prior page of the access
terminal 102. For example, at some other point in time the network
node 106 may have sent a page request to the access point 104
instructing the access point 104 to page the access terminal 102.
As discussed above, such a page request may include idle context
information such as a page identifier and an indication of page
timing.
[0071] As represented by block 506, the access point 104 (e.g., the
paging controller 328) may thus maintain the idle context of the
access terminal 102 for use in one or more subsequent paging
operations. For example, the access point 104 may temporarily store
the page identifier and page timing information (or other
information derived from the idle context) in a data memory.
[0072] As represented by block 508, at some point in time the
access point 104 receives a local breakout packet destined for the
access terminal 102. The access point 104 (e.g., the paging
controller 328) may thus retrieve the idle context for this access
terminal, and page the access terminal 102 using the idle context
as represented by block 510. That is, the access point 104 may send
a page comprising the page identifier at a time designated by the
page timing information.
[0073] The operations of FIG. 5 may be implemented in various ways.
In some implementations the access terminal 104 may acquire the
idle context when the access terminal 102 connects to the access
point 104. For example, the access point 104 may send a request for
the idle context after a registration message from the access
terminal 102 is received by the access point 104 (e.g., the
communication controller 322). In some implementations the access
terminal 104 may acquire the idle context after receiving the local
packet. For example, the access point 104 may send a request for
the idle context after receiving the packet. In such a case, the
access point 104 may continue to maintain the idle context for
subsequent packets or may acquire new context each time a packet or
set of packets is received (i.e., the context is maintained for
only a short period of time).
[0074] Referring to FIG. 6, operations relating to a sample
implementation where the access point 104 filters local breakout
packets destined for the access terminal 102 will be described in
more detail. In this example, the access point 104 filters out all
non-unicast packets. It should be appreciated that different types
of packets may be filtered (e.g., only broadcast packets) in other
cases.
[0075] As represented by block 602, at some point in time the
access point 104 receives a local breakout packet destined for the
access terminal 102. For example, the packet may be received at the
packet processor 334 which may be configured to process the packet
to identify a packet type associated with the packet (block 604).
For example, the packet type may indicate whether the packet is a
unicast packet or a non-unicast packet (e.g., a broadcast packet or
a multicast packet).
[0076] As represented by block 606, the access point 104 (e.g., the
packet filter 340) selectively filters the received packet based on
the determined packet type. For example, if the access terminal 102
is not in an active mode (e.g., the access terminal 102 is in a
power saving idle mode), the access point 104 may elect to not page
the access terminal 102 in response to the receipt of a non-unicast
packet via the local breakout. Conversely, if the access terminal
102 is in an active mode (e.g., the access terminal 102 is actively
communicating with the access point 104), the access point 104 may
elect to not deliver a local breakout non-unicast packet to the
access terminal 102.
[0077] The scheme of FIG. 6 thus reduces power consumption of the
access terminal 102 by reducing the number of pages or packets sent
to the access terminal 102. However, this scheme limits the
usability of the local breakout feature to some extent. For
example, it is preferable for the access terminal 102 to receive at
least some broadcast packets so that the access terminal 102 may
discover the devices that are connected on the network (e.g., a
printer). In this way, the access terminal 102 may be able to
readily communicate with such devices when requested by a user.
[0078] Referring to FIG. 7, operations relating to a sample
implementation where an access point selectively filters local
breakout packets destined for the access terminal 102 will be
described in more detail. In this example, the access point 104
filters out non-unicast packets based on the current operating mode
of the access terminal 102. For example, in a regular operating
mode the access terminal 102 is not paged for any broadcast packets
to conserve battery power. In this case, the access terminal 102
only communicates with the other devices on the local network via
unicast IP addresses. As a result, the access terminal 102 may not
perform service discovery on the local network during this mode of
operation. In contrast, in a broadcast-enabled operating mode, all
packets (e.g., including broadcast and multicast packets) may be
forwarded to the access terminal 102. In this mode, the access
terminal 102 may perform service discovery on the local network. It
should be appreciated that different types of packets may be
filtered (e.g., only broadcast packets) in other cases and/or the
selective filtering may be based on some other criterion or
criteria in other cases.
[0079] As represented by block 702, at various points in time the
access terminal 102 may select an operating mode that indicates
whether the access terminal 102 is to be paged for certain types of
packets. For example, at certain times the access terminal 102
(e.g., the mode controller 336) may elect to only receive unicast
packets while at other times the access terminal 102 may elect to
receive all packets (e.g., unicast and non-unicast packets).
[0080] The election of block 702 may be made in various ways. In
some cases a user may initiate this election. For example, if the
user decides that he or she wishes to access a local service (e.g.,
a printer on a home network), the user may manipulate a user input
device of the access terminal 102 to enable paging for non-unicast
packets. Otherwise, the user may place the access terminal 102 in a
unicast-only mode. In these cases, the mode controller 336 may
receive a signal from the input device to make the election.
[0081] In some cases an application on the access terminal 102 may
make the election of block 702. For example, if an application
determines that it (or some other application) needs to access a
local service (e.g., a printer on a home network), the application
may autonomously switch the operating mode to enable paging for
non-unicast packets. In some cases, this determination may be based
on some action of a user (e.g., invocation of an application such
as a printing application). In addition, an application may cause
the access terminal 102 to automatically revert back to the
unicast-only mode (e.g., after a period of time or upon termination
of a local access).
[0082] As represented by block 704, the access terminal 102 (e.g.,
the communication controller 320) sends an indication of the
selected mode to the access point 104. This indication may be sent
in various ways.
[0083] In some implementations the indication is sent via a layer 2
("L2") air interface protocol between the access terminal 102 and
the access point 104. This technique may thus require support from
each air interface technology used by the access terminal 102 and
the access point 104.
[0084] In some implementations the indication is sent via a layer 3
("L3") protocol between the access terminal 102 and the access
point 104. For example, a service discovery/advertisement protocol
may be enhanced to convey the mode of the access terminal 102 to
the access point 104. A potential protocol for accomplishing this
is UPnP. Using UPnP, the access terminal 102 sends device
advertisement messages, which contain information about the access
terminal 102 and the mode it will be operating in (e.g., regular or
broadcast-enabled). A discussed below, the access point 104
intercepts this message and controls the broadcast addressed packet
delivery accordingly. Advantageously, the L3 technique may be air
interface technology independent and may be utilized by any air
interface technology.
[0085] The access point 104 receives the indication as represented
by block 706. Accordingly, the access point 104 (e.g., the mode
controller 338) may determine the operating mode of the access
terminal 102 as represented by block 708.
[0086] As represented by block 710, at some point in time the
access point 104 receives a local breakout packet destined for the
access terminal 102. In addition, at block 712 the access point 104
may determine the type of this packet as discussed herein (e.g., if
the access terminal 102 is operating in unicast-only mode). For
example, the packet processor 334 may determine whether the packet
is a non-unicast packet or a unicast packet.
[0087] As represented by block 714, the access point 104 (e.g., the
paging controller 328) may then determine whether to page the
access terminal 102 in response to the receipt of the packet. In
some aspects, this determination may be based on the operating mode
of the access terminal 102. In addition, this determination may be
based on the determined packet type (e.g., if the access terminal
is operating in unicast-only mode).
[0088] Referring to FIG. 8, operations relating to a sample
implementation where an access terminal may elect to ignore a local
breakout packet received at an access point will be described in
more detail. In this example, the access point includes an
indication of packet type when paging the access terminal to enable
the access terminal to make this decision.
[0089] As represented by block 802, at some point in time the
access point 104 receives a local breakout packet destined for the
access terminal 102. In addition, at block 804 the access point 104
determines a packet type of this packet as discussed herein. For
example, the packet processor 334 may determine whether the packet
is one or more of: a unicast packet, a non-unicast packet, a
broadcast packet, a local breakout packet, a network packet (e.g.,
received via a core network of a cellular network), a packet of a
particular protocol, associated with a particular port number
(e.g., a TCP port or UDP port), and so on.
[0090] As represented by block 806, the access point 104 (e.g., the
paging controller 328) pages the access terminal 102 in response to
the receipt of the packet. In this case, the page comprises an
indication of the packet type determined at block 804. For example,
the indication may comprise one or more bits that have been added
to the page, or the indication may be encoded in the page. As a
specific example, two bits may be added to the page message as
follows: A first bit indicates whether the page is to deliver a
packet from the local breakout interface or from operator's core
network; while a second bit indicates whether the page is to
deliver a packet with a unicast IP address or a non-unicast (e.g.,
broadcast/multicast) IP address.
[0091] The access terminal 102 (e.g., the paging controller 326)
receives the page as represented by block 808. Accordingly, as
represented by block 810, the access terminal 102 (e.g., the packet
processor 332) may determine whether to receive the packet based on
the packet type. For example, the access terminal 102 may elect to
not receive certain types of packets (e.g., at certain times) to
conserve battery power. In some implementations, the decision to
receive a particular type of packet may be based on user input
and/or a decision made by an application as discussed above in
conjunction with block 702.
[0092] As represented by blocks 812 and 814, if the access terminal
102 elects to not receive the packet, the access terminal 102 may
simply continue idle mode operations. That is, the access terminal
102 may continue with its normal sleep cycle instead of switching
to active mode to retrieve the packet from the access point
104.
[0093] Conversely, if the access terminal 102 elects to receive the
packet, the access terminal 102 may switch to active mode operation
as represented by block 816. In this case, the access terminal 102
accesses the access point 104 to retrieve the packet.
[0094] Through the use of the power management scheme of FIG. 8,
the access terminal 102 may implement algorithms to optimize its
battery usage and connectivity. Moreover, this scheme does not need
an interface between the access terminal 102 and the access point
104. To fully utilize this solution, some user interaction may be
needed. For example, a user may put the access terminal 102 in
scanning mode, in which case the access terminal 102 may wake up
for all broadcast packets to discover all the other devices in a
local (e.g., home) network. In regular mode, the access terminal
102 may not wake up for page messages that indicate a non-unicast
page.
[0095] Referring to FIG. 9, operations relating to a sample
implementation where an access terminal may selectively enable and
disable a local link interface will be described in more detail.
Here, the local link interface may be provided between the access
terminal 102 and the access point 104 (that provides local breakout
for the access terminal 102).
[0096] As represented by block 902, the access terminal 102 (e.g.,
the communication controller 320) determines whether access to a
local network (i.e., local breakout) is needed. For example, the
access terminal 102 may elect to turn off its local link interface
when the local link has been idle for a certain amount of time so
that the access terminal 102 will not be paged for any packet on
the local link.
[0097] As represented by blocks 904 and 906, if local access is not
needed, the access terminal 102 (e.g., the communication controller
320) disables the local link interface. For example, the access
terminal 102 may release the corresponding IP address and "switch
off" the corresponding L2 link. In some implementations, to save
additional power, the access terminal 102 may turn off one or more
components associated with the local link interface.
[0098] As represented by block 908, if local access is needed, the
access terminal 102 keeps the local link enabled or re-enables the
link. For example, if the local link had been disable, when the
access terminal 102 needs a local breakout service, the link would
be re-established (e.g., in a broadcast-enabled mode).
[0099] As represented by blocks 910 and 912, the access terminal
102 may continue processing network packets (e.g., packets to and
from the core network of a cellular network) irrespective of
whether the local link is enabled.
[0100] If the access terminal 102 later needs to access a local
service (e.g., send a print job) the access terminal 102 may: 1)
connect and thereby enable the local link interface (block 908); 2)
discover the local services (e.g., printer); 3) process local
network packets at block 914 (e.g., send a print job); and 4)
disconnect, if desired (thereby disabling the local link interface
again at block 906). An advantage of this scheme is that there may
be no change to default access point behavior or no need for a new
protocol to exchange mode information. If the access terminal 102
needs to stay on for a long period (e.g., to send streaming video)
the access terminal 102 may simply receive all local network (e.g.,
broadcast) packets as well.
[0101] As mentioned above, the teachings herein may be employed in
a network that includes macro scale coverage (e.g., a large area
cellular network such as a 3G network, typically referred to as a
macro cell network or a WAN) and smaller scale coverage (e.g., a
residence-based or building-based network environment, typically
referred to as a LAN). As an access terminal ("AT") moves through
such a network, the access terminal may be served in certain
locations by access points that provide macro coverage while the
access terminal may be served at other locations by access points
that provide smaller scale coverage. In some aspects, the smaller
coverage nodes may be used to provide incremental capacity growth,
in-building coverage, and different services (e.g., for a more
robust user experience). A node (e.g., an access point) that
provides coverage over a relatively large area may be referred to
as a macro node while a node that provides coverage over a
relatively small area (e.g., a residence) may be referred to as a
femto node. Similar principles may be applicable to nodes
associated with other types of coverage areas. For example, a pico
node may provide coverage (e.g., coverage within a commercial
building) over an area that is smaller than a macro area and larger
than a femto area.
[0102] In various applications, other terminology may be used to
reference a macro node, a femto node, or other access point-type
nodes. For example, a macro node may be configured or referred to
as an access node, base station, access point, eNodeB, macro cell,
and so on. Also, a femto node may be configured or referred to as a
Home NodeB, Home eNodeB, access point base station, femto cell, and
so on. In some implementations, a node may be associated with
(e.g., divided into) one or more cells or sectors. A cell or sector
associated with a macro node, a femto node, or a pico node may be
referred to as a macro cell, a femto cell, or a pico cell,
respectively.
[0103] FIG. 10 illustrates a wireless communication network 1000,
configured to support a number of users, in which the teachings
herein may be implemented. The system 1000 provides communication
for multiple cells 1002, such as, for example, macro cells
1002A-1002G, with each cell being serviced by a corresponding
access point 1004 (e.g., access points 1004A-1004G). As shown in
FIG. 10, access terminals 1006 (e.g., access terminals 1006A-1006L)
may be dispersed at various locations throughout the system over
time. Each access terminal 1006 may communicate with one or more
access points 1004 on a forward link ("FL") and/or a reverse link
("RL) at a given moment, depending upon whether the access terminal
1006 is active and whether it is in soft handoff, for example. The
wireless communication network 1000 may provide service over a
large geographic region. For example, macro cells 1002A-1002G may
cover a few blocks in a neighborhood or several miles in rural
environment.
[0104] FIG. 11 illustrates an exemplary communication system 1100
where one or more femto nodes are deployed within a network
environment (e.g., network 1000). Specifically, the system 1100
includes multiple femto nodes 1110 (e.g., femto nodes 1110A and
1110B) installed in a relatively small scale network environment
(e.g., in one or more user residences 1130). Each femto node 1110
may be coupled to a wide area network 1140 (e.g., the Internet) and
a mobile operator core network 1150 via a DSL router, a cable
modem, a wireless link, or other connectivity means (not shown). As
will be discussed below, each femto node 1110 may be configured to
serve associated access terminals 1120 (e.g., access terminal
1120A) and, optionally, other (e.g., hybrid or alien) access
terminals 1120 (e.g., access terminal 1120B). In other words,
access to femto nodes 1110 may be restricted whereby a given access
terminal 1120 may be served by a set of designated (e.g., home)
femto node(s) 1110 but may not be served by any non-designated
femto nodes 1110 (e.g., a neighbor's femto node 1110).
[0105] FIG. 12 illustrates an example of a coverage map 1200 where
several tracking areas 1202 (or routing areas or location areas)
are defined, each of which includes several macro coverage areas
1204. Here, areas of coverage associated with tracking areas 1202A,
1202B, and 1202C are delineated by the wide lines and the macro
coverage areas 1204 are represented by the larger hexagons. The
tracking areas 1202 also include femto coverage areas 1206. In this
example, each of the femto coverage areas 1206 (e.g., femto
coverage area 1206C) is depicted within one or more macro coverage
areas 1204 (e.g., macro coverage area 1204B). It should be
appreciated, however, that some or all of a femto coverage area
1206 may not lie within a macro coverage area 1204. In practice, a
large number of femto coverage areas 1206 may be defined with a
given tracking area 1202 or macro coverage area 1204. Also, one or
more pico coverage areas (not shown) may be defined within a given
tracking area 1202 or macro coverage area 1204.
[0106] Referring again to FIG. 11, the owner of a femto node 1110
may subscribe to mobile service, such as, for example, 3G mobile
service, offered through the mobile operator core network 1150. In
addition, an access terminal 1120 may be capable of operating both
in macro environments and in smaller scale (e.g., residential)
network environments as discussed above. In other words, depending
on the current location of the access terminal 1120, the access
terminal 1120 may be served by a macro cell access point 1160
associated with the mobile operator core network 1150 or by any one
of a set of femto nodes 1110 (e.g., the femto nodes 1110A and 1110B
that reside within a corresponding user residence 1130). For
example, when a subscriber is outside his home, he is served by a
standard macro access point (e.g., access point 1160) and when the
subscriber is at home, he is served by a femto node (e.g., node
1110A). Here, a femto node 1110 may be backward compatible with
legacy access terminals 1120.
[0107] A femto node may be restricted in some aspects. For example,
a given femto node may only provide certain services to certain
access terminals. In deployments with so-called restricted (or
closed) association, a given access terminal may only be served by
the macro cell mobile network and a defined set of femto nodes
(e.g., the femto nodes 1110 that reside within the corresponding
user residence 1130). In some implementations, a node may be
restricted to not provide, for at least one node, at least one of:
signaling, data access, registration, paging, or service.
[0108] In some aspects, a restricted femto node (which may also be
referred to as a Closed Subscriber Group Home NodeB) is one that
provides service to a restricted provisioned set of access
terminals. This set may be temporarily or permanently extended as
necessary. In some aspects, a Closed Subscriber Group ("CSG") may
be defined as the set of access points (e.g., femto nodes) that
share a common access control list of access terminals.
[0109] Various relationships may thus exist between a given femto
node and a given access terminal. For example, from the perspective
of an access terminal, an open femto node may refer to a femto node
with no restricted association (e.g., the femto node allows access
to any access terminal). A restricted femto node may refer to a
femto node that is restricted in some manner (e.g., restricted for
association and/or registration). A home femto node may refer to a
femto node on which the access terminal is authorized to access and
operate on (e.g., permanent access is provided for a defined set of
one or more access terminals). A guest femto node may refer to a
femto node on which an access terminal is temporarily authorized to
access or operate on. An alien femto node may refer to a femto node
on which the access terminal is not authorized to access or operate
on, except for perhaps emergency situations (e.g., 911 calls).
[0110] From a restricted femto node perspective, a home access
terminal may refer to an access terminal that is authorized to
access the restricted femto node (e.g., the access terminal has
permanent access to the femto node). A guest access terminal may
refer to an access terminal with temporary access to the restricted
femto node (e.g., limited based on deadline, time of use, bytes,
connection count, or some other criterion or criteria). An alien
access terminal may refer to an access terminal that does not have
permission to access the restricted femto node, except for perhaps
emergency situations, for example, such as 911 calls (e.g., an
access terminal that does not have the credentials or permission to
register with the restricted femto node).
[0111] For convenience, the disclosure herein describes various
functionality in the context of a femto node. It should be
appreciated, however, that a pico node may provide the same or
similar functionality for a larger coverage area. For example, a
pico node may be restricted, a home pico node may be defined for a
given access terminal, and so on.
[0112] A wireless multiple-access communication system may
simultaneously support communication for multiple wireless access
terminals. Each terminal may communicate with one or more access
points via transmissions on the forward and reverse links. The
forward link (or downlink) refers to the communication link from
the access points to the terminals, and the reverse link (or
uplink) refers to the communication link from the terminals to the
access points. This communication link may be established via a
single-in-single-out system, a multiple-in-multiple-out ("MIMO")
system, or some other type of system.
[0113] A MIMO system employs multiple (N.sub.T) transmit antennas
and multiple (N.sub.R) receive antennas for data transmission. A
MIMO channel formed by the N.sub.T transmit and N.sub.R receive
antennas may be decomposed into N.sub.S independent channels, which
are also referred to as spatial channels, where N.sub.S.ltoreq.min
{N.sub.T, N.sub.R}. Each of the N.sub.S independent channels
corresponds to a dimension. The MIMO system may provide improved
performance (e.g., higher throughput and/or greater reliability) if
the additional dimensionalities created by the multiple transmit
and receive antennas are utilized.
[0114] A MIMO system may support time division duplex ("TDD") and
frequency division duplex ("FDD"). In a TDD system, the forward and
reverse link transmissions are on the same frequency region so that
the reciprocity principle allows the estimation of the forward link
channel from the reverse link channel. This enables the access
point to extract transmit beam-forming gain on the forward link
when multiple antennas are available at the access point.
[0115] The teachings herein may be incorporated into a node (e.g.,
a device) employing various components for communicating with at
least one other node. FIG. 13 depicts several sample components
that may be employed to facilitate communication between nodes.
Specifically, FIG. 13 illustrates a wireless device 1310 (e.g., an
access point) and a wireless device 1350 (e.g., an access terminal)
of a MIMO system 1300. At the device 1310, traffic data for a
number of data streams is provided from a data source 1312 to a
transmit ("TX") data processor 1314.
[0116] In some aspects, each data stream is transmitted over a
respective transmit antenna. The TX data processor 1314 formats,
codes, and interleaves the traffic data for each data stream based
on a particular coding scheme selected for that data stream to
provide coded data.
[0117] The coded data for each data stream may be multiplexed with
pilot data using OFDM techniques. The pilot data is typically a
known data pattern that is processed in a known manner and may be
used at the receiver system to estimate the channel response. The
multiplexed pilot and coded data for each data stream is then
modulated (i.e., symbol mapped) based on a particular modulation
scheme (e.g., BPSK, QSPK, M-PSK, or M-QAM) selected for that data
stream to provide modulation symbols. The data rate, coding, and
modulation for each data stream may be determined by instructions
performed by a processor 1330. A data memory 1332 may store program
code, data, and other information used by the processor 1330 or
other components of the device 1310.
[0118] The modulation symbols for all data streams are then
provided to a TX MIMO processor 1320, which may further process the
modulation symbols (e.g., for OFDM). The TX MIMO processor 1320
then provides N.sub.T modulation symbol streams to N.sub.T
transceivers ("XCVR") 1322A through 1322T. In some aspects, the TX
MIMO processor 1320 applies beam-forming weights to the symbols of
the data streams and to the antenna from which the symbol is being
transmitted.
[0119] Each transceiver 1322 receives and processes a respective
symbol stream to provide one or more analog signals, and further
conditions (e.g., amplifies, filters, and upconverts) the analog
signals to provide a modulated signal suitable for transmission
over the MIMO channel. N.sub.T modulated signals from transceivers
1322A through 1322T are then transmitted from N.sub.T antennas
1324A through 1324T, respectively.
[0120] At the device 1350, the transmitted modulated signals are
received by N.sub.R antennas 1352A through 1352R and the received
signal from each antenna 1352 is provided to a respective
transceiver ("XCVR") 1354A through 1354R. Each transceiver 1354
conditions (e.g., filters, amplifies, and downconverts) a
respective received signal, digitizes the conditioned signal to
provide samples, and further processes the samples to provide a
corresponding "received" symbol stream.
[0121] A receive ("RX") data processor 1360 then receives and
processes the N.sub.R received symbol streams from N.sub.R
transceivers 1354 based on a particular receiver processing
technique to provide N.sub.T "detected" symbol streams. The RX data
processor 1360 then demodulates, deinterleaves, and decodes each
detected symbol stream to recover the traffic data for the data
stream. The processing by the RX data processor 1360 is
complementary to that performed by the TX MIMO processor 1320 and
the TX data processor 1314 at the device 1310.
[0122] A processor 1370 periodically determines which pre-coding
matrix to use (discussed below). The processor 1370 formulates a
reverse link message comprising a matrix index portion and a rank
value portion. A data memory 1372 may store program code, data, and
other information used by the processor 1370 or other components of
the device 1350.
[0123] The reverse link message may comprise various types of
information regarding the communication link and/or the received
data stream. The reverse link message is then processed by a TX
data processor 1338, which also receives traffic data for a number
of data streams from a data source 1336, modulated by a modulator
1380, conditioned by the transceivers 1354A through 1354R, and
transmitted back to the device 1310.
[0124] At the device 1310, the modulated signals from the device
1350 are received by the antennas 1324, conditioned by the
transceivers 1322, demodulated by a demodulator ("DEMOD") 1340, and
processed by a RX data processor 1342 to extract the reverse link
message transmitted by the device 1350. The processor 1330 then
determines which pre-coding matrix to use for determining the
beam-forming weights then processes the extracted message.
[0125] FIG. 13 also illustrates that the communication components
may include one or more components that perform paging/power
control operations as taught herein. For example, a paging/power
control component 1390 may cooperate with the processor 1330 and/or
other components of the device 1310 to send/receive signals to/from
another device (e.g., device 1350) as taught herein. Similarly, a
paging/power control component 1392 may cooperate with the
processor 1370 and/or other components of the device 1350 to
send/receive signals to/from another device (e.g., device 13 10).
It should be appreciated that for each device 1310 and 1350 the
functionality of two or more of the described components may be
provided by a single component. For example, a single processing
component may provide the functionality of the paging/power control
component 1390 and the processor 1330 and a single processing
component may provide the functionality of the paging/power control
component 1392 and the processor 1370.
[0126] The teachings herein may be incorporated into various types
of communication systems and/or system components. In some aspects,
the teachings herein may be employed in a multiple-access system
capable of supporting communication with multiple users by sharing
the available system resources (e.g., by specifying one or more of
bandwidth, transmit power, coding, interleaving, and so on). For
example, the teachings herein may be applied to any one or
combinations of the following technologies: Code Division Multiple
Access ("CDMA") systems, Multiple-Carrier CDMA ("MCCDMA"), Wideband
CDMA ("W-CDMA"), High-Speed Packet Access ("HSPA," "HSPA+")
systems, Time Division Multiple Access ("TDMA") systems, Frequency
Division Multiple Access ("FDMA") systems, Single-Carrier FDMA
("SC-FDMA") systems, Orthogonal Frequency Division Multiple Access
("OFDMA") systems, or other multiple access techniques. A wireless
communication system employing the teachings herein may be designed
to implement one or more standards, such as IS-95, cdma2000,
IS-856, W-CDMA, TDSCDMA, and other standards. A CDMA network may
implement a radio technology such as Universal Terrestrial Radio
Access ("UTRA)", cdma2000, or some other technology. UTRA includes
W-CDMA and Low Chip Rate ("LCR"). The cdma2000 technology covers
IS-2000, IS-95 and IS-856 standards. A TDMA network may implement a
radio technology such as Global System for Mobile Communications
("GSM"). An OFDMA network may implement a radio technology such as
Evolved UTRA ("E-UTRA"), IEEE 802.11, IEEE 802.16, IEEE 802.20,
Flash-OFDM.RTM., etc. UTRA, E-UTRA, and GSM are part of Universal
Mobile Telecommunication System ("UMTS"). The teachings herein may
be implemented in a 3GPP Long Term Evolution ("LTE") system, an
Ultra-Mobile Broadband ("UMB") system, and other types of systems.
LTE is a release of UMTS that uses E-UTRA. Although certain aspects
of the disclosure may be described using 3GPP terminology, it is to
be understood that the teachings herein may be applied to 3GPP
(Rel99, Rel5, Rel6, Rel7) technology, as well as 3GPP2 (IxRTT,
IxEV-DO RelO, RevA, RevB) technology and other technologies.
[0127] The teachings herein may be incorporated into (e.g.,
implemented within or performed by) a variety of apparatuses (e.g.,
nodes). In some aspects, a node (e.g., a wireless node) implemented
in accordance with the teachings herein may comprise an access
point or an access terminal.
[0128] For example, an access terminal may comprise, be implemented
as, or known as user equipment, a subscriber station, a subscriber
unit, a mobile station, a mobile, a mobile node, a remote station,
a remote terminal, a user terminal, a user agent, a user device, or
some other terminology. In some implementations an access terminal
may comprise a cellular telephone, a cordless telephone, a session
initiation protocol ("SIP") phone, a wireless local loop ("WLL")
station, a personal digital assistant ("PDA"), a handheld device
having wireless connection capability, or some other suitable
processing device connected to a wireless modem. Accordingly, one
or more aspects taught herein may be incorporated into a phone
(e.g., a cellular phone or smart phone), a computer (e.g., a
laptop), a portable communication device, a portable computing
device (e.g., a personal data assistant), an entertainment device
(e.g., a music device, a video device, or a satellite radio), a
global positioning system device, or any other suitable device that
is configured to communicate via a wireless medium.
[0129] An access point may comprise, be implemented as, or known as
a NodeB, an eNodeB, a radio network controller ("RNC"), a base
station ("BS"), a radio base station ("RBS"), a base station
controller ("BSC"), a base transceiver station ("BTS"), a
transceiver function ("TF"), a radio transceiver, a radio router, a
basic service set ("BSS"), an extended service set ("ESS"), a macro
cell, a macro node, a Home eNB ("HeNB"), a femto cell, a femto
node, a pico node, or some other similar terminology.
[0130] In some aspects a node (e.g., an access point) may comprise
an access node for a communication system. Such an access node may
provide, for example, connectivity for or to a network (e.g., a
wide area network such as the Internet or a cellular network) via a
wired or wireless communication link to the network. Accordingly,
an access node may enable another node (e.g., an access terminal)
to access a network or some other functionality. In addition, it
should be appreciated that one or both of the nodes may be portable
or, in some cases, relatively non-portable.
[0131] Also, it should be appreciated that a wireless node may be
capable of transmitting and/or receiving information in a
non-wireless manner (e.g., via a wired connection). Thus, a
receiver and a transmitter as discussed herein may include
appropriate communication interface components (e.g., electrical or
optical interface components) to communicate via a non-wireless
medium.
[0132] A wireless node may communicate via one or more wireless
communication links that are based on or otherwise support any
suitable wireless communication technology. For example, in some
aspects a wireless node may associate with a network. In some
aspects the network may comprise a local area network or a wide
area network. A wireless device may support or otherwise use one or
more of a variety of wireless communication technologies,
protocols, or standards such as those discussed herein (e.g., CDMA,
TDMA, OFDM, OFDMA, WiMAX, Wi-Fi, and so on). Similarly, a wireless
node may support or otherwise use one or more of a variety of
corresponding modulation or multiplexing schemes. A wireless node
may thus include appropriate components (e.g., air interfaces) to
establish and communicate via one or more wireless communication
links using the above or other wireless communication technologies.
For example, a wireless node may comprise a wireless transceiver
with associated transmitter and receiver components that may
include various components (e.g., signal generators and signal
processors) that facilitate communication over a wireless
medium.
[0133] The functionality described herein (e.g., with regard to one
or more of the accompanying figures) may correspond in some aspects
to similarly designated "means for" functionality in the appended
claims. Referring to FIGS. 14-21, apparatuses 1400, 1500, 1600,
1700, 1800, 1900, 2000, and 2100 are represented as a series of
interrelated functional modules. Here, a packet receiving module
1402 may correspond at least in some aspects to, for example, a
packet processor as discussed herein. A paging module 1404, an idle
context maintaining module 1406, an idle context acquiring module
1408, and a page request idle context maintaining module 1412 may
each correspond at least in some aspects to, for example, a paging
controller as discussed herein. A registration message receiving
module 1410 may correspond at least in some aspects to, for
example, a communication controller as discussed herein. A message
receiving module 1502 may correspond at least in some aspects to,
for example, a communication controller as discussed herein. A
message sending module 1504 may correspond at least in some aspects
to, for example, a paging controller as discussed herein. A page
determining module 1506 may correspond at least in some aspects to,
for example, a paging controller as discussed herein. A packet
receiving module 1602 and a packet type determining module 1604 may
each correspond at least in some aspects to, for example, a packet
processor as discussed herein. A selective filtering module 1606
may correspond at least in some aspects to, for example, a packet
filter as discussed herein. An operating mode determining module
1702 may correspond at least in some aspects to, for example, a
mode controller as discussed herein. A packet receiving module 1704
and a packet type determining module 1706 may each correspond at
least in some aspects to, for example, a packet processor as
discussed herein. A page determining module 1708 may correspond at
least in some aspects to, for example, a paging controller as
discussed herein. An operating mode electing module 1802 may
correspond at least in some aspects to, for example, a mode
controller as discussed herein. An indication sending module 1804
may correspond at least in some aspects to, for example, a
communication controller as discussed herein. A packet receiving
module 1902 and a packet type determining module 1904 may each
correspond at least in some aspects to, for example, a packet
processor as discussed herein. A page sending module 1906 may
correspond at least in some aspects to, for example, a paging
controller as discussed herein. A page receiving module 2002 may
correspond at least in some aspects to, for example, a paging
controller as discussed herein. A packet reception determining
module 2004 may correspond at least in some aspects to, for
example, a packet processor as discussed herein. An access
determining module 2102 may correspond at least in some aspects to,
for example, a mode controller as discussed herein. A local link
interface disabling module 2104 may correspond at least in some
aspects to, for example, a communication controller as discussed
herein.
[0134] The functionality of the modules of FIGS. 14-21 may be
implemented in various ways consistent with the teachings herein.
In some aspects the functionality of these modules may be
implemented as one or more electrical components. In some aspects
the functionality of these blocks may be implemented as a
processing system including one or more processor components. In
some aspects the functionality of these modules may be implemented
using, for example, at least a portion of one or more integrated
circuits (e.g., an ASIC). As discussed herein, an integrated
circuit may include a processor, software, other related
components, or some combination thereof. The functionality of these
modules also may be implemented in some other manner as taught
herein. In some aspects one or more of any dashed blocks in FIGS.
14-21 are optional.
[0135] It should be understood that any reference to an element
herein using a designation such as "first," "second," and so forth
does not generally limit the quantity or order of those elements.
Rather, these designations may be used herein as a convenient
method of distinguishing between two or more elements or instances
of an element. Thus, a reference to first and second elements does
not mean that only two elements may be employed there or that the
first element must precede the second element in some manner. Also,
unless stated otherwise a set of elements may comprise one or more
elements. In addition, terminology of the form "at least one of: A,
B, or C" used in the description or the claims means "A or B or C
or any combination of these elements."
[0136] Those of skill in the art would understand that information
and signals may be represented using any of a variety of different
technologies and techniques. For example, data, instructions,
commands, information, signals, bits, symbols, and chips that may
be referenced throughout the above description may be represented
by voltages, currents, electromagnetic waves, magnetic fields or
particles, optical fields or particles, or any combination
thereof.
[0137] Those of skill would further appreciate that any of the
various illustrative logical blocks, modules, processors, means,
circuits, and algorithm steps described in connection with the
aspects disclosed herein may be implemented as electronic hardware
(e.g., a digital implementation, an analog implementation, or a
combination of the two, which may be designed using source coding
or some other technique), various forms of program or design code
incorporating instructions (which may be referred to herein, for
convenience, as "software" or a "software module"), or combinations
of both. To clearly illustrate this interchangeability of hardware
and software, various illustrative components, blocks, modules,
circuits, and steps have been described above generally in terms of
their functionality. Whether such functionality is implemented as
hardware or software depends upon the particular application and
design constraints imposed on the overall system. Skilled artisans
may implement the described functionality in varying ways for each
particular application, but such implementation decisions should
not be interpreted as causing a departure from the scope of the
present disclosure.
[0138] The various illustrative logical blocks, modules, and
circuits described in connection with the aspects disclosed herein
may be implemented within or performed by an integrated circuit
("IC"), an access terminal, or an access point. The IC may comprise
a general purpose processor, a digital signal processor (DSP), an
application specific integrated circuit (ASIC), a field
programmable gate array (FPGA) or other programmable logic device,
discrete gate or transistor logic, discrete hardware components,
electrical components, optical components, mechanical components,
or any combination thereof designed to perform the functions
described herein, and may execute codes or instructions that reside
within the IC, outside of the IC, or both. A general purpose
processor may be a microprocessor, but in the alternative, the
processor may be any conventional processor, controller,
microcontroller, or state machine. A processor may also be
implemented as a combination of computing devices, e.g., a
combination of a DSP and a microprocessor, a plurality of
microprocessors, one or more microprocessors in conjunction with a
DSP core, or any other such configuration.
[0139] It is understood that any specific order or hierarchy of
steps in any disclosed process is an example of a sample approach.
Based upon design preferences, it is understood that the specific
order or hierarchy of steps in the processes may be rearranged
while remaining within the scope of the present disclosure. The
accompanying method claims present elements of the various steps in
a sample order, and are not meant to be limited to the specific
order or hierarchy presented.
[0140] In one or more exemplary embodiments, the functions
described may be implemented in hardware, software, firmware, or
any combination thereof. If implemented in software, the functions
may be stored on or transmitted over as one or more instructions or
code on a computer-readable medium. Computer-readable media
includes both computer storage media and communication media
including any medium that facilitates transfer of a computer
program from one place to another. A storage media may be any
available media that can be accessed by a computer. By way of
example, and not limitation, such computer-readable media can
comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage,
magnetic disk storage or other magnetic storage devices, or any
other medium that can be used to carry or store desired program
code in the form of instructions or data structures and that can be
accessed by a computer. Also, any connection is properly termed a
computer-readable medium. For example, if the software is
transmitted from a website, server, or other remote source using a
coaxial cable, fiber optic cable, twisted pair, digital subscriber
line (DSL), or wireless technologies such as infrared, radio, and
microwave, then the coaxial cable, fiber optic cable, twisted pair,
DSL, or wireless technologies such as infrared, radio, and
microwave are included in the definition of medium. Disk and disc,
as used herein, includes compact disc (CD), laser disc, optical
disc, digital versatile disc (DVD), floppy disk and blu-ray disc
where disks usually reproduce data magnetically, while discs
reproduce data optically with lasers. Combinations of the above
should also be included within the scope of computer-readable
media. It should be appreciated that a computer-readable medium may
be implemented in any suitable computer-program product.
[0141] The previous description of the disclosed aspects is
provided to enable any person skilled in the art to make or use the
present disclosure. Various modifications to these aspects will be
readily apparent to those skilled in the art, and the generic
principles defined herein may be applied to other aspects without
departing from the scope of the disclosure. Thus, the present
disclosure is not intended to be limited to the aspects shown
herein but is to be accorded the widest scope consistent with the
principles and novel features disclosed herein.
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