U.S. patent application number 12/957180 was filed with the patent office on 2011-06-02 for handoff in a self-configuring communication system.
This patent application is currently assigned to SpiderCloud Wireless, Inc.. Invention is credited to Yashwanth Hemaraj, Darshan Purohit, Brett Schein, Murari Srinivasan.
Application Number | 20110130144 12/957180 |
Document ID | / |
Family ID | 44068849 |
Filed Date | 2011-06-02 |
United States Patent
Application |
20110130144 |
Kind Code |
A1 |
Schein; Brett ; et
al. |
June 2, 2011 |
HANDOFF IN A SELF-CONFIGURING COMMUNICATION SYSTEM
Abstract
Methods, devices, and computer program products facilitate
various handoff operations to/from a network. A self-configuring
and self-optimizing topology discovery operation provides detailed
information regarding the various radio nodes that are internal and
external to the network. This information is utilized to construct
a plurality of neighbor lists that identify multiple tiers of
neighboring radio nodes of the network. The neighbor lists and the
measurements obtained from the user equipment within the network
provide up-to-date information that facilitates various types of
handoff operations.
Inventors: |
Schein; Brett; (San Jose,
CA) ; Hemaraj; Yashwanth; (Milpitas, CA) ;
Srinivasan; Murari; (Palo Alto, CA) ; Purohit;
Darshan; (Fremont, CA) |
Assignee: |
SpiderCloud Wireless, Inc.
|
Family ID: |
44068849 |
Appl. No.: |
12/957180 |
Filed: |
November 30, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61265700 |
Dec 1, 2009 |
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Current U.S.
Class: |
455/442 ;
455/436; 455/446 |
Current CPC
Class: |
H04L 41/12 20130101;
H04W 48/16 20130101; H04W 24/02 20130101 |
Class at
Publication: |
455/442 ;
455/436; 455/446 |
International
Class: |
H04W 36/00 20090101
H04W036/00; H04W 16/24 20090101 H04W016/24 |
Claims
1. A method, comprising: constructing a neighbor list associated
with a particular radio node within a network pursuant to an
automated network topology discovery; receiving information
associated with measurements made by user equipment associated with
the particular node; and mapping neighboring radio nodes of the
particular radio node pursuant to the received information to
facilitate a handoff operation.
2. The method of claim 1, further comprising communicating at least
a portion of the constructed neighbor list to one or more user
equipment.
3. The method of claim 1, wherein the automated network topology
discovery assesses characteristics of a plurality of radio nodes
that are within communication range of the network.
4. The method of claim 2, wherein the plurality of radio nodes
comprise radio nodes internal to the network and radio nodes
external to the network.
5. The method of claim 1, wherein the constructed neighbor list
comprises information indicative as to whether each neighboring
radio node is internal to the network or external to the
network.
6. The method of claim 1, wherein the constructed neighbor list
comprises signaling information associated with each neighboring
radio node.
7. The method of claim 1, wherein the constructed neighbor list
comprises information associated with a radio node selected from
the group consisting of: a directly scanned radio node; a
first-tier radio node; a second- or higher-tier radio node; and a
radio node that is suitable for a handoff operation.
8. The method of claim 2, wherein the communicating comprises
broadcasting or unicasting at least a portion of the constructed
neighbor list.
9. The method of claim 1, wherein the handoff operation is selected
from a group of handoff operations consisting of: a soft handoff
operation; a softer handoff operation; a hard handoff operation; an
inter-radio access technology handoff operation; an inter-frequency
handoff operation; and an intra-frequency handoff operation.
10. The method of claim 1, wherein: the received information
relates to a radio node internal to the network; and the radio node
internal to the network is selected as a candidate for a soft
handoff operation.
11. The method of claim 1, wherein: the received information
relates to a radio node external to the network; and the radio node
external to the network is selected as a candidate for a hard
handoff operation.
12. The method of claim 1, further comprising: receiving
information associated with measurements from user equipment
associated with other radio nodes internal to the network; and
mapping neighboring radio nodes of the other radio nodes.
13. A method for adding a new radio node to a network, comprising:
scanning a portion of the network to obtain identities of
neighboring radio nodes that are detectable by the new radio node;
constructing a first-tier neighbor list associated with the new
radio node; and mapping an identifier of the new radio node in
accordance with the first-tier neighbor list.
14. The method of claim 13, wherein the mapping of the identifier
of the new radio node comprises associating a primary scrambling
code with an identification information of the new radio node.
15. The method of claim 13, further comprising reconstructing a
neighbor list associated with at least one radio node other than
the new radio node to reflect a presence of the new radio node.
16. The method of claim 15, wherein the scanning of a portion of
the network identifies the at least one radio node other than the
new radio node.
17. The method of claim 15, wherein the at least one radio node
other than the new radio node is a first-tier scanned neighbor of
the new radio node; and the reconstructing comprises updating the
neighbor list associated with at least one radio node other than
the new radio node to include identification information of the new
radio node based on radio frequency reciprocity.
18. The method of claim 15, wherein the at least one radio node
other than the new radio node is a first-tier scanned neighbor of
the new radio node; and the reconstructing comprises using the at
least one radio node other than the new radio node to conduct a
scan of the network, and updating the neighbor list associated with
at least one radio node other than the new radio node to include
identification information of the new radio node, if the new radio
node is detected as a result of the scan of the network.
19. The method of claim 14, wherein the identification information
comprises at least one of a network controller identity (RNCID), a
cell identifier (CID) and a public land mobile network
identification (PLMNID).
20. The method of claim 13, further comprising updating the
constructed first-tier neighbor list associated with the new radio
node to include multiple tiers of neighboring radio nodes.
21. The method of claim 13, further comprising: receiving
information associated with measurements made by one or more user
equipment.
22. The method of claim 15, wherein at least a portion of the
reconstructed neighbor list is communicated to the one or more user
equipment.
23. The method of claim 21, wherein a mapping of radio nodes is
updated pursuant to the received information.
24. A method for facilitating a hand-in operation from an external
entity to a network, comprising: selecting an external radio node
associated with the external entity; creating a neighbor list
associated with the external radio node, the neighbor list
comprising information associated with one or more candidate radio
nodes, the one or more candidate radio nodes being internal radio
nodes of the network; and communicating the neighbor list to the
external entity to facilitate the hand-in operation.
25. The method of claim 24, wherein the information associated with
the one or more candidate radio nodes are obtained pursuant to an
automated network topology discovery.
26. The method of claim 24, wherein the neighbor list comprises
information associated with first-tier neighbors of the external
radio node.
27. The method of claim 24, wherein the neighbor list comprises
information associated with all radio nodes internal to the
network.
28. The method of claim 24, wherein the neighbor list is created in
accordance with information provided by the internal radio nodes of
the network.
29. The method of claim 24, wherein the communicating comprises
broadcasting or unicasting, by an internal network entity, at least
a portion of the neighbor list to the external entity.
30. A method for facilitating a hand-in operation to a network,
comprising: receiving a neighbor list from an entity internal to
the network at an external network entity, the neighbor list
comprising one or more candidate internal radio nodes for the
hand-in operation; receiving a measurement report from a user
equipment associated with the external entity, the measurement
report comprising an identifier of an internal radio node; mapping
the identifier to a particular internal radio node on the received
neighbor list; producing a hand-out indication; and commencing the
hand-in operation to the particular internal radio node.
31. The method of claim 30, wherein upon the reception of the
neighbor list, a neighbor list associated with an external radio
node is updated.
32. The method of claim 30, wherein the hand-out indication is
produced as part of a serving radio network subsystem (SRNS)
RELOCATION REQUIRED message.
33. The method of claim 30, wherein the identifier is a primary
scrambling code.
34. A device, comprising: a processor; and a memory comprising
processor executable code, the processor executable code, when
executed by the processor, configures the apparatus to: construct a
neighbor list associated with a particular radio node within a
network pursuant to an automated network topology discovery;
receive information associated with measurements made by user
equipment associated with the particular node; and map neighboring
radio nodes of the particular radio node pursuant to the received
information to facilitate a handoff operation.
35. A computer program product, embodied on a computer readable
medium, comprising: program code for constructing a neighbor list
associated with a particular radio node within a network pursuant
to an automated network topology discovery; program code for
receiving information associated with measurements made by user
equipment associated with the particular node; and program code for
mapping neighboring radio nodes of the particular radio node
pursuant to the received information to facilitate a handoff
operation.
36. A device for adding a new radio node to a network, comprising:
a processor; and a memory comprising processor executable code, the
processor executable code, when executed by the processor,
configures the apparatus to: scan a portion of a network to obtain
identities of neighboring radio nodes that are detectable by the
new radio node; construct a first-tier neighbor list associated
with the new radio node; and map an identifier of the new radio
node in accordance with the first-tier neighbor list.
37. A computer program product, embodied on a computer readable
medium, for adding a new radio node to a network, comprising:
program code for scanning a portion of a network to obtain
identities of neighboring radio nodes that are detectable by the
new radio node; program code for constructing a first-tier neighbor
list associated with the new radio node; and program code for
mapping an identifier of the new radio node in accordance with the
first-tier neighbor list.
38. A device for facilitating a hand-in operation from an external
entity to a network, comprising: a processor; and a memory
comprising processor executable code, the processor executable
code, when executed by the processor, configures the apparatus to:
select an external radio node associated with the external entity;
create a neighbor list associated with the external radio node, the
neighbor list comprising information associated with one or more
candidate radio nodes, the one or more candidate radio nodes being
internal radio nodes of the network; and communicate the neighbor
list to the external entity to facilitate the hand-in
operation.
39. A computer program product, embodied on a computer readable
medium, for facilitating a hand-in operation from an external
entity to a network, comprising: program code for selecting an
external radio node associated with the external entity; program
code for creating a neighbor list associated with the external
radio node, the neighbor list comprising information associated
with one or more candidate radio nodes, the one or more candidate
radio nodes being internal radio nodes of the network; and program
code for communicating the neighbor list to the external entity to
facilitate the hand-in operation.
40. A device for facilitating a hand-in operation to a network,
comprising: a processor; and a memory comprising processor
executable code, the processor executable code, when executed by
the processor, configures the apparatus to: receive a neighbor list
from an entity internal to the network at an external network
entity, the neighbor list comprising one or more candidate internal
radio nodes for the hand-in operation; produce a hand-in
indication; receive a measurement report from a user equipment
associated with the external entity, the measurement report
comprising an identifier of an internal radio node; map the
identifier to a particular internal radio node on the received
neighbor list; and commence the hand-in operation to the particular
internal radio node.
41. A computer program product, embodied on a computer readable
medium, for facilitating a hand-in operation to a network,
comprising: program code for receiving a neighbor list from an
entity internal to the network at an external network entity, the
neighbor list comprising one or more candidate internal radio nodes
for the hand-in operation; program code for producing a hand-in
indication; program code for receiving a measurement report from a
user equipment associated with the external entity, the measurement
report comprising an identifier of an internal radio node; program
code for mapping the identifier to a particular internal radio node
on the received neighbor list; and program code for commencing the
hand-in operation to the particular internal radio node.
Description
CROSS REFERENCE TO RELATED APPLICATION(S)
[0001] The present application claims priority to U.S. Provisional
Patent Application Ser. No. 61/265,700, titled "METHOD, SYSTEM AND
DEVICE FOR CONFIGURING TOPOLOGY OF A WIRELESS NETWORK," filed on
Dec. 1, 2009, the entirety of which is hereby incorporated by
reference.
FIELD OF INVENTION
[0002] The present invention relates generally to the field of
wireless communications. More particularly, the present invention
relates to facilitating handoff operations in a wireless
communication system.
BACKGROUND
[0003] This section is intended to provide a background or context
to the invention that is recited in the claims. The description
herein may include concepts that could be pursued, but are not
necessarily ones that have been previously conceived or pursued.
Therefore, unless otherwise indicated herein, what is described in
this section is not prior art to the description and claims in this
application and is not admitted to be prior art by inclusion in
this section.
[0004] In cellular networks, radio nodes, also sometimes referred
to as base stations, access points, cells, Node Bs, eNode Bs, and
the like, are normally installed and commissioned after a careful
upfront planning and survey process, which is followed by extensive
post installation optimization efforts to maximize the network
performance. Such optimization efforts usually involve a
considerable amount of manual intervention that could include
"drive testing" using specialized measurement devices to collect
data on network performance at a variety of geographical locations.
This data is then post-processed and analyzed to effect
optimization steps including power adjustments, antenna tilt
adjustments and the like.
[0005] Such prior planning, installation and post-installation
efforts can become cost prohibitive for networks that cover
complicated physical spaces spanning multiple floors of a building,
including elevator shafts, stairwells, atria and meeting rooms. In
addition, expensive planning, installation and post-installation
procedures often do not make business sense for small-cell (e.g.,
local area) networks that are installed and operated relatively
inexpensively. In particular, the cost of installation procedures
may be prohibitive in enterprise networks that are described
herein, as well as applications that relate to high-density
capacity enhancements of a downtown city square and ad-hoc
deployment of a cellular network such as in military applications.
Nevertheless, proper configuration and optimization of an
enterprise network is important for enabling efficient utilization
of network resources, as well as conducting operations such as
handoffs between and within the networks.
SUMMARY OF THE INVENTION
[0006] The disclosed embodiments relate to methods, devices, and
computer program products that facilitate various handoff
operations by providing relevant and up-date-information related to
the identity and availability of radio resources within and
external to a network. One of the aspects of the disclosed
embodiments relates to a method that includes constructing a
neighbor list associated with a particular radio node within a
network pursuant to an automated network topology discovery. This
method further includes receiving information associated with
measurements made by user equipment associated with the particular
node, and mapping neighboring radio nodes of the particular radio
node pursuant to the received information to facilitate a handoff
operation.
[0007] In one embodiment, the above-noted method further comprises
communicating at least a portion of the constructed neighbor list
to one or more user equipment. In another embodiment, the automated
network topology discovery assesses characteristics of a plurality
of radio nodes that are within communication range of the network.
In one variation, the plurality of radio nodes comprise radio nodes
internal to the network and radio nodes external to the network.
According to another embodiment, the constructed neighbor list
comprises information indicative as to whether each neighboring
radio node is internal to the network or external to the
network.
[0008] In another embodiment, the constructed neighbor list
comprises signaling information associated with each neighboring
radio node. In yet another embodiment, the constructed neighbor
list comprises information associated with a radio node selected
from the group consisting of: a directly scanned radio node, a
first-tier radio node, a second- or higher-tier radio node, and a
radio node that is suitable for a handoff operation. According to
another embodiment, method of claim 1, wherein the communicating of
at least a portion of the constructed neighbor list comprises
broadcasting or unicasting the portion of the constructed neighbor
list.
[0009] In one embodiment, the above-mentioned handoff operation is
selected from a group of handoff operations consisting of: a soft
handoff operation, a softer handoff operation, a hard handoff
operation, an inter-radio access technology handoff operation, an
inter-frequency handoff operation, and an intra-frequency handoff
operation. In another embodiment, where the received information
from the user equipment relates to a radio node internal to the
network, the radio node internal to the network is selected as a
candidate for a soft handoff operation. In still another
embodiment, where, the received information relates to a radio node
external to the network, the radio node external to the network is
selected as a candidate for a hard handoff operation.
[0010] According to another embodiment, the above-noted method
further comprises receiving information associated with
measurements from user equipment associated with other radio nodes
internal to the network, and mapping neighboring radio nodes of the
other radio nodes.
[0011] Another aspect of the disclosed embodiments relates to a
method for adding a new radio node to a network. Such a method
includes scanning a portion of the network to obtain identities of
neighboring radio nodes that are detectable by the new radio node,
and constructing a first-tier neighbor list associated with the new
radio node. This method further comprises mapping an identifier of
the new radio node in accordance with the first-tier neighbor list.
In one embodiment, the mapping of the identifier of the new radio
node comprises associating a primary scrambling code with an
identification information of the new radio node.
[0012] According to another embodiment, the above-noted method for
adding a new radio node further includes reconstructing a neighbor
list associated with at least one radio node other than the new
radio node to reflect a presence of the new radio node. In one
variation, the scanning of a portion of the network identifies the
at least one radio node other than the new radio node. In another
variation, the at least one radio node other than the new radio
node is a first-tier scanned neighbor of the new radio node, and
the reconstructing of the neighbor list comprises updating the
neighbor list associated with at least one radio node other than
the new radio node to include identification information of the new
radio node based on radio frequency reciprocity.
[0013] In another embodiment, where the at least one radio node
other than the new radio node is a first-tier scanned neighbor of
the new radio node, the reconstructing of the neighbor list
comprises using the at least one radio node other than the new
radio node to conduct a scan of the network. In this embodiment,
the reconstructing of the neighbor list also includes updating the
neighbor list associated with at least one radio node other than
the new radio node to include identification information of the new
radio node, if the new radio node is detected as a result of the
scan of the network.
[0014] According to another embodiment, the identification
information of the new radio node comprises at least one of a
network controller identity (RNCID), a cell identifier (CID) and a
public land mobile network identification (PLMNID). In another
embodiment, the above-noted method for adding a new radio node
further includes updating the constructed first-tier neighbor list
associated with the new radio node to include multiple tiers of
neighboring radio nodes. In still another embodiment, such a method
additionally includes receiving information associated with
measurements made by one or more user equipment.
[0015] In one embodiment, at least a portion of the reconstructed
neighbor list is communicated to the one or more user equipment. In
another embodiment, a mapping of radio nodes is updated pursuant to
the received information.
[0016] Another aspect of the disclosed embodiments relates to a
method for facilitating a hand-in operation from an external entity
to a network. Such a method comprises selecting an external radio
node associated with the external entity and creating a neighbor
list associated with the external radio node, where the neighbor
list comprises information associated with one or more candidate
radio nodes and such one or more candidate radio nodes are internal
radio nodes of the network. This method also includes communicating
the neighbor list to the external entity to facilitate the hand-in
operation. In one embodiment, the information associated with the
one or more candidate radio nodes are obtained pursuant to an
automated network topology discovery.
[0017] In another embodiment, the neighbor list comprises
information associated with first-tier neighbors of the external
radio node. In yet another embodiment, the neighbor list comprises
information associated with all radio nodes internal to the
network. In still another embodiment, the neighbor list is created
in accordance with information provided by the internal radio nodes
of the network.
[0018] According to another embodiment, the above-noted method for
facilitating a hand-in operation from an external entity further
includes receiving the neighbor list, and creating a constructed
neighbor list by the external node. In another embodiment, the
communicating of the neighbor list to the external entity comprises
broadcasting or unicasting, by an internal network entity, at least
a portion of the neighbor list to the external entity.
[0019] Another aspect of the disclosed embodiments also relates to
a method for facilitating a hand-in operation to a network. Such a
method comprises receiving a neighbor list from an entity internal
to the network at an external network entity, where the neighbor
list comprises one or more candidate internal radio nodes for the
hand-in operation. This method also includes receiving a
measurement report from a user equipment associated with the
external entity, where the measurement report comprising an
identifier of an internal radio node. Additionally, the method
comprises mapping the identifier to a particular internal radio
node on the received neighbor list, producing a hand-in indication
and commencing the hand-in operation to the particular internal
radio node.
[0020] In one embodiment, upon the reception of the neighbor list,
a neighbor list associated with an external radio node is updated.
In another embodiment, the hand-in indication is received as part
of a serving radio network subsystem (SRNS) RELOCATION REQUIRED
message. In still another embodiment, the identifier is a primary
scrambling code.
[0021] Other aspects of the disclosed embodiments relate to devices
that are configured to carry out the various operations of the
disclosed methods. For example, such devices can include a
processor and a memory that includes a processor executable code.
The processor executable code, when executed by the processor,
configures the device to carry out various operations that
facilitate handoff operations.
[0022] Additional aspects of the disclosed embodiments relate to
computer program products that are embodied on one or more
non-transitory computer readable media. Such computer program
products comprise computer code for carrying out the operations of
the various disclosed embodiments.
[0023] These and other advantages and features of various
embodiments of the present invention, together with the
organization and manner of operation thereof, will become apparent
from the following detailed description when taken in conjunction
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Embodiments of the invention are described by referring to
the attached drawings, in which:
[0025] FIG. 1 illustrates an exemplary network within which the
disclosed embodiments can be implemented;
[0026] FIG. 2 illustrates an exemplary universal mobile
telecommunication system (UMTS) terrestrial radio access network
(UTRAN) within which the disclosed embodiments can be
implemented;
[0027] FIG. 3 illustrates an exemplary enterprise radio access
network (E-RAN) within which the disclosed embodiments can be
implemented;
[0028] FIG. 4 is a block diagram illustrating operations that are
conducted to facilitate handoff operations in accordance with an
example embodiment;
[0029] FIG. 5 is a simplified diagram that illustrates multi-tier
neighbors in a cellular network;
[0030] FIG. 6 is a block diagram illustrating external cell
discovery in accordance with an example embodiment;
[0031] FIG. 7 is a block diagram illustrating broadcast channel
(BCH) decoding in accordance with an example embodiment;
[0032] FIG. 8 is a block diagram illustrating cell power assignment
operations in accordance with an example embodiment;
[0033] FIG. 9 is a block diagram illustrating operations that are
conducted to add a new radio node in accordance with an example
embodiment;
[0034] FIG. 10 is a block diagram illustrating operations that are
conducted by an internal entity to facilitate a hand-in operation
in accordance with an example embodiment;
[0035] FIG. 11 is a block diagram illustrating operations that are
conducted by an external entity to facilitate a hand-in operation
in accordance with an example embodiment; and
[0036] FIG. 12 is a block diagram of an example device for
implementing the various disclosed embodiments.
DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS
[0037] In the following description, for purposes of explanation
and not limitation, details and descriptions are set forth in order
to provide a thorough understanding of the present invention.
However, it will be apparent to those skilled in the art that the
present invention may be practiced in other embodiments that depart
from these details and descriptions.
[0038] Additionally, in the subject description, the word
"exemplary" is used to mean serving as an example, instance, or
illustration. Any embodiment or design described herein as
"exemplary" is not necessarily to be construed as preferred or
advantageous over other embodiments or designs. Rather, use of the
word exemplary is intended to present concepts in a concrete
manner. Further, some of the disclosed embodiments are described in
the context of an enterprise network. However, it should be
understood that the disclosed concepts are equally applicable to
other types of networks.
[0039] The disclosed embodiments facilitate various types of
handoff operations. A handoff, which is sometimes referred to as a
handover, refers to the transfer of an ongoing communication
session (e.g., a voice or data session) from one radio link to
another radio link. The transfer of the on-going session can be to
another network (e.g., to a network with a different radio access
technology (RAT) or an inter-RAT handoff), to another cell, to
another sector of the same cell, to another frequency within the
same cell and the like. Additionally, or alternatively, the various
handoff scenarios may be described in terms of inter-frequency and
intra-frequency handoff operations. Inter-frequency handoff refers
to adding a radio link for service to the user equipment on a
different logical entity which uses a different channel frequency,
such as a neighboring cell operating on a different frequency.
Inter-frequency handoff can, but does not necessarily, include
terminating the radio link on the source cell (i.e., a hard handoff
that is described in sections that follow). Intra-frequency handoff
refers to adding a radio link on a different logical entity which
uses the same channel frequency. Further, the term "cell" may be
construed in different ways. For example, a cell can be considered
a logical entity that manages a single radio channel (i.e., the
typical definition in the context of Universal Mobile
Telecommunications System (UMTS)). In other examples, a cell may be
considered a logical entity that manages multiple radio channels,
usually on different frequencies. In still other examples, a cell
may can be construed as a logical entity that manages multiple
radio channels, on the same or different frequencies, that have
been sectorized. In other scenarios, a cell can be considered a
physical area covered adequately by RF energy from a particular
sector of a physical base station installation, which can include
just one RF channel or multiple RF channels. In yet other examples,
a cell can be construed as a physical area covered adequately by RF
energy from all sectors of a physical base station installation,
which can also include one or multiple RF channels.
[0040] The disclosed embodiments also facilitate different types of
handoffs that are known as hard, soft and softer handoffs. In a
hard handoff, the connection to the existing radio link is broken
before the connection to the new radio link is established. In a
soft handoff, the existing radio link is retained and used in
parallel with one or more newly acquired radio links of the target
cell(s). The simultaneous connections in a soft handoff may be for
a brief or substantial period of time. A softer handoff, which is
used in Universal Mobile Telecommunications System (UMTS), is a
special case of a soft handoff, where the radio links that are used
in parallel belong to the same Node B.
[0041] A handoff can be initiated for a variety of reasons. For
example, a user equipment that moves to another geographical area,
which is outside of the coverage area of its existing cell, may
initiate a handoff to avoid termination of the on-going session. In
another example, a handoff to another cell may be initiated to free
up resources at an existing cell. In yet another example, a handoff
is used to improve interference from other channels. In order to
initiate a handoff, the user equipment must be aware of potential
target cells (i.e., neighboring radio nodes) that are likely to
accommodate the handoff. The information regarding the neighboring
radio nodes are often provided in a listing that is often referred
to a neighbor list. In the context of an enterprise network,
neighbor radio nodes may include both radio nodes that are internal
to the enterprise network and the ones that operate outside of the
enterprise network.
[0042] FIG. 1 illustrates an exemplary system 100 which may be used
to accommodate some or all of the disclosed embodiments. The system
100 can, for example, be an enterprise network. The system 100
includes a plurality of access points referenced as 101, 102, 104,
106, 108 and 112. The access points that are illustrated in FIG. 1
are connected, directly or indirectly, to an access controller 114
through connection 120. Each of the access points 101, 102, 104,
106, 108 and 112 is herein referred to as an "internal access
point" (or an "internal radio node"). Each internal access point
may communicate with a plurality of user equipment (UE), as well as
other access points. It should be noted that while FIG. 1
illustrates a single central controller 114 that is distinct from
the access points, it is also possible that the access controller
is implemented as part of one or more access points. Further, the
various embodiments of the present invention may also be
implemented using a peer-to-peer network of access points, where
each access point can initiate certain transmissions, including
commands and/or data, to other access points without the
involvement of a central controller.
[0043] The exemplary block diagram that is shown in FIG. 1 is
representative of a single network that may be adjacent to, or
partially overlapping with, other networks. The collection of these
other networks, which may comprise macro-cellular networks,
femtocell networks and the like, are herein referred to as the
external networks. Each "external network" may comprise one or more
access controllers and a plurality of "external access points" (or
"external radio nodes").
[0044] FIG. 2 is another exemplary diagram of a radio network 200,
such as a Universal Mobile Telecommunication System (UMTS)
Terrestrial Radio Access Network (UTRAN), that can accommodate the
various disclosed embodiments. The network that is depicted in FIG.
2 comprises a Core Network (CN) 202, one or more Radio Network
Controllers (RNC) 204a that are in communication with a plurality
of Node Bs 206a and 206b (or base stations or radio nodes) and
other RNCs 202b. Each Node B 206a, 206b is in communication with
one or more UEs 208a, 208b and 208c. There is one serving cell
controlling the serving radio link assigned to each UE 208a, 208b
and 208c. However, as illustrated in FIG. 2 with a dashed line, a
UE 208a may be in communication with more than one Node B. For
example, a Node B of a neighboring cell may communicate with one or
more UEs of the current cell during handoffs and/or to provide
overload indications. While FIG. 2 depicts an exemplary radio
network in a UMTS system, the disclosed embodiments may be extended
to operate with other systems and networks such as CDMA2000, WiMAX,
LTE and the like.
[0045] FIG. 3 illustrates an exemplary Enterprise Radio Access
Network (E-RAN) 300 that can be used to accommodate the various
disclosed embodiments. The E-RAN 300 includes a services node 304
and a plurality of radio nodes 306a, 306 b and 306c. It should be
noted that the E-RAN 300 can include fewer or additional radio
nodes and/or additional services nodes. The services node 304 is
the central control point of the overall cluster of radio nodes
306a, 306b and 306c that are deployed throughout the enterprise
campus 302. The services node 304, which can be deployed inside the
enterprise local area network (LAN) provides, for example, session
management for all mobile sessions delivered by the radio nodes
306a, 306b and 306c. Each of the radio nodes 306a, 306b and 306c
are in communication with one or more UEs (not depicted). The radio
nodes 306a, 306b and 306c can support a multi-radio architecture
that allows a flexible upgrade path to higher user counts, as well
as the ability to support different radio access technologies. In
one example, the E-RAN 300 configuration allows the creation of a
unified mobile corporate network that integrates mobile workers
distributed throughout the overall enterprise domain with centrally
located corporate assets. FIG. 3 also illustrates an operator 308
that is in communication with the services node 304, which can
monitor the operations of the services node 304 and can provide
various input and control parameters to the services node 304. The
interactivity between the operator 308 and the services node 304
can be provided through, for example, a command line interface
(CLI) and/or industry-standard device configuration protocols, such
as TR-69 or TR-196.
[0046] It should be noted that while the exemplary radio networks
that are depicted in FIGS. 1-3 all include a central controller,
the disclosed embodiments are equally applicable to non-centralized
network architectures. Such architectures can, for example,
comprise isolated home Node Bs, radio nodes and/or a
femtocell-based enterprise deployments that do not use a central
controller.
[0047] One of the problems associated with configuration and set up
of enterprise networks is that the system is not programmed with
the locations of the radio nodes, the desired coverage area of the
network, a listing of radio nodes that are considered neighbors of
each other for internal handoff purposes, or the relevant external
radio nodes (or their signaling parameters) for hand-in/hand-out
from/to external networks. Creating the neighbor lists and
acquiring information related to network coverage area are not
trivial tasks and, as noted earlier, require various measurements,
planning and post-installation tuning operations. Traditional
macro-cellular approaches require extensive RF mapping and RF
planning, drive tests with specialized measurement devices and
manual configuration. The manual configuration includes manually
configuring the neighbor lists for every radio node in the
network.
[0048] The disclosed embodiments facilitate different types of
handoff operations, including, but not limited to, soft handoffs,
intra-frequency hard handoffs and inter-frequency hard handoffs.
The disclosed embodiments take advantage of self-configuration
techniques that enable an automated discovery of external and
internal radio nodes that are connected in a radio frequency (RF)
sense. Such self-configuration techniques further allow an
intelligent assignment of primary scrambling/spreading codes (PSC)
and facilitate the various types of handoffs between and within the
networks, all with no, or minimal, manual intervention. The
disclosed self-configuration features provide a complete assessment
and mapping of the RF environment associated with internal and
external radio nodes and accurately identify multiple tiers of
neighboring radio nodes, as well as the associated signaling
parameters. This discovery of network topology further enables the
addition of new cells to the network and allows the propagation of
relevant information to an external entity to conduct hand-in
operations. It should be noted that in some embodiments a handoff
operation may be more specifically described by using the terms
"hand-in" and "hand-out." A hand-in operation is associated with
receiving an on-going session that is transferred into the current
network from an external network, while a hand-out operation is
associated with the transfer of an on-going session out from the
current network to an external network.
[0049] To enable the various operations that are carried out in
some of the disclosed embodiments, the radio nodes within the
internal network (e.g., the enterprise network and/or a network
that is configured within a larger network) are configured to make
measurements of the broadcast transmissions made by other radio
nodes within the internal network, as well as in external cells. In
particular, broadcast transmissions that are mandated by, for
example, UMTS R99, Rels. 5 to 9, as well as future 3GPP standard
drafts may be used to acquire the necessary measurement
information. The U.S. patent application Ser. No. 12/487,277,
titled "METHODS AND APPARATUS FOR COORDINATING NETWORK MONITORING
AND/OR AUTOMATING DEVICE CONFIGURATIONS BASED ON MONITORING
RESULTS," which claims the benefit of the filing date of U.S.
provisional application No. 61/073,747 filed on Jun. 18, 2008, and
is assigned to the present assignee, describes example techniques
related to conducting certain measurements through broadcast
information transmissions. This application is hereby incorporated
by reference in its entirety.
[0050] Once the measurements are made, a controller, such as the
central controller that is depicted in FIG. 1, may be used to
coordinate the measurements made by the access points, such that
the final set of measurements are collated easily for processing in
accordance with the algorithms that are described below. The
processing algorithms derive information about the internal
topology and the external or neighboring networks and produce
"neighbor lists." These lists comprise identification information
corresponding to the first- and second-tier neighbors of each
access point within both the internal and external networks. For
example, this identification information may comprise both the
received signal strengths from each access point, as well as
protocol signaling parameters. Based on the pooled measurement
information, and the neighbor lists, primary scrambling codes (PSC)
may be assigned to internal access points. The assignment is
carried out to minimize the downlink interference between internal
access points, as well as between the internal and external cells.
Further, the assignment of the same PSC to different first-tier
neighbors of the same (external or internal) cell is avoided.
[0051] It should be also noted that the term internal node or
internal radio node are used to refer to radio nodes that are
controlled by the internal network. Further, the terms internal
cell and internal radio node are sometimes used interchangeably to
describe cells with associated radio nodes that are internal to the
radio network.
[0052] Using the standards-mandated measurement reporting
capability of the UEs allows a subset of UEs to be configured to
deliver periodic measurement reports to their serving access
points. This provides an accurate sampling of the propagation
conditions within the deployment region at locations where users
are expected to be present. The periodic measurement reporting,
unlike events-based reporting, provides an unbiased sampling of the
propagation environment, regardless whether the RF conditions are
good, bad, changing, or nearly static. Due to the periodic nature
of these measurements, however, the data associated with the
on-going measurements may become too large for efficient handling
and/or storage. The disclosed embodiments address this issue by
processing and condensing the information obtained from a number of
measurements into a critical set of measurements that is sufficient
to assign transmit powers to the access points to satisfy the
desired operating conditions. The computational and storage
requirements associated with such processing can be kept relatively
small by processing the incoming measurement data on-the-fly.
[0053] According to another embodiment, the above-noted critical
set of UE measurements are processed to produce a set of assigned
transmit powers for all access points and to identify possible
coverage "holes" in the network. In particular, coverage holes can
be identified by noting the locations where a transmit power
assignment cannot satisfy the desired operating conditions for a
particular critical point. Once the initial power assignment has
taken place, the periodic UE measurements may be used to
subsequently reassign transmit powers to different access points.
Furthermore, subsequent, but infrequent, full scanning may be
carried out to refresh the system's knowledge of internal and
external cells and neighbors.
[0054] Using some or all of the above-noted techniques, together
with stored operating and topology information, it is possible to
quickly recover from system-wide shutdowns, such as power outages,
without repeating the entire topology-discovery and measurement
procedures. In addition, since the topology and access point
characteristics of the network is known, new access points may be
readily added and certain access points may be readily deleted from
the network. It should be also noted that the various disclosed
embodiments provide a detailed assessment and automated
configuration of the access network with no, or little, human
involvement. In addition, they provide inter-cell coordination that
is necessary to pool and process the collected information to
obtain the topology information and optimized parameter settings
for the network components.
[0055] FIG. 4 is a block diagram illustrating some the
self-configuration operations that are conducted to facilitate the
various handoff operations pursuant to the disclosed embodiments.
In step 402, external cell discovery takes place. This step
involves using one or more access points to assess the presence and
strength of external networks. In one example, each internal radio
node is configured to conduct scans to discover external cells.
Such scans may reveal both signal strength and signaling parameters
associated with the external cells that are required for hand-out
and, potentially, for hand-in operations. In an alternate
embodiment, an operator may configure information regarding
external cells. For example, the operator can include the
configured cell(s) as neighbors. Alternatively, the operator can
exclude the configured cell(s) as neighbors. These configuration
operations can be carried out according to the TR-69 and TR-196
standards. In other examples, the result of external cell discovery
can be combined with the above noted operator configuration steps.
For example, the information that is obtained during the detection
and decoding of the cells as part of the external cell discovery
process can be augmented by the operator input to allow the
operator to configure particular cells that are preferred for
handout, to configure cells that are discouraged for hand-out, to
update the information with current loading on particular cells, to
include particular capabilities or preferences that are not
broadcast, and the like.
[0056] Referring to back to FIG. 4, step 402 can further include
detecting the primary scrambling codes (PSCs) that are used by the
external neighbors. Once the PSC of a cell has been identified, the
PSCs of its neighboring cells can be detected by decoding UMTS
system information block 11 (SIB11), SIB11bis and/or SIB12 on the
broadcast channel (BCCH). This knowledge can be used to avoid PSC
collision when new PSCs are assigned. To illustrate this feature,
let's assume an external cell X with an associated downlink PSC 1
broadcasts SIB11, indicating cell X has another external cell
neighbor Y with downlink PSC 2. Let's further assume that when an
external cell topology discovery is conducted using internal cell
Z, external cell X is detected while external cell Y remains
undetected. By decoding cell X's SIB11, however, internal cell Z
can ascertain that cell X (with PSC 1) has a neighbor with PSC 2,
and avoid assigning PSC 2 to cell Z. Assigning PSC 2 to cell Z can
interfere with the operations of cell X since if a user equipment
in cell X reported a "good" cell with PSC 2, it would be unclear
whether the UE is referring to cell Y or to cell Z.
[0057] The external cell discovery of step 402 can include using a
radio node to scan multiple channels (e.g., Universal Terrestrial
Radio Access Absolute Radio Frequency Channel Number (UARFCN)
downlink channels, hereinafter "UARFCNDL"). Based on the
measurements of the multiple channels, a single channel may be
designated for use with the radio node. As such, the network may
potentially designate a different UARFCNDL for each radio node. For
example, multiple UARFCNDL can be assigned to minimize interference
between cells on the same UARFCNDL. In one example, the UARFCNDL is
assigned to produce maximally spread UARFCNDL values. Such an
assignment can be conducted similar to the assignment of PSCs,
which will be described in connection with step 406 of FIG. 4.
[0058] In other embodiments, the same UARFCNDL is assigned to all
radio nodes within the network. The assignment of a single UARFCNDL
can facilitate soft handoffs in UMTS or CDMA, where only soft
handoffs between cells on the same UARFCN are supported. In one
example, the particular value of the UARFCNDL is assigned by an
operator. In some scenarios, the operator does not have a large
number of channels available. For example, only two channel numbers
may be available, where one is assigned to the macro network and
the other is used for the local or enterprise network. In another
example, a single UARFCNDL can be selected pursuant to the scanning
and measurement of external signal strengths on each allowable
UARFCNDL during the external cell discovery (at step 402 of FIG.
4). In this example, a particular UARFCNDL with the smallest
measured signal strength, or minimum external interference can be
selected.
[0059] Referring back to FIG. 4, in step 404, internal topology
discovery is conducted. In one embodiment, one access point is
selected and placed in the operational mode while the remaining
access points of the internal network are placed in the monitoring
mode. In this embodiment, the operating radio node broadcasts using
a particular PSC, while every other radio node attempts to detect
the particular PSC. The selection of the particular PSC may be
carried out with the help of information obtained during the
above-described external cell discovery. For example, a particular
PSC may be selected such that the maximum received signal code
power (RSCP) measured over all access points is minimized. More
specifically, if a PSC was not detected by any of the access
points, that particular PSC is selected. Failing to find such an
undetected PSC, a PSC that has not been strongly detected by any of
the access points during the external discovery is chosen.
[0060] As part of the operations in step 404, if a radio node is
able to detect the particular PSC, the detecting radio node is
considered a first-tier neighbor of the transmitting radio node. In
some embodiments, the transmitting radio node is also considered a
first-tier neighbor of the detecting radio node due to RF
reciprocity. This process may be repeated by placing each radio
node, one at-a-time, in operational mode while placing the
remaining radio nodes in monitoring mode to identify all the
neighbors within the network. It should be noted that an ambiguity
may arise if a monitoring access point which had previously
detected the PSC during the external discovery process makes the
detection during the internal discovery process. In one embodiment,
the controller may decide to mark the operational access point as a
first-tier neighbor if the newly measured PSC strength exceeds the
one found during the external discovery process by a particular
threshold.
[0061] The neighbors that are produced according to the above
operations represent a limited collection of "scanned" neighbors
for each radio node that may be placed on a neighbor list
associated with that radio node. However, as will be described in
the sections that follow, according to the disclosed embodiments,
an expanded neighbor list is also constructed (i.e., a "constructed
neighbor list") for each radio node that includes additional
neighbors. Such a constructed neighbor list includes the identity
and other information associated with multiple tiers of neighbors
that can be candidates for a handoff operation. As such, the cells
that are listed on a constructed neighbor list are sometimes
referred to as a "handoff" neighbor.
[0062] In an alternate embodiment, more than one access point may
be configured to operate in the operational mode to allow faster
internal topology discovery. For example, after a first radio node
is placed in the operational mode for a given amount of time, a
second radio node is placed in the operational mode. The remaining
radio nodes that are still monitoring then determine whether or not
they can detect the second radio node that just become operational.
If the second radio node is detected, the detecting radio node is
considered a first-tier neighbor of the second radio node and, by
reciprocity, the second radio node is considered a first-tier
neighbor of the detecting radio node. In another variation, a
similar detection procedure is carried out while two or more radio
nodes with different PSCs are simultaneously placed in the
operational mode. The groups of operational access points selected
for simultaneous transmission may be chosen, for example, at random
or based on the discovered external topology so that they are
unlikely to be neighbors.
[0063] In describing the various disclosed embodiments, references
are made to multi-tier neighbor lists. The following is a
simplified example that, with the help of FIG. 5, facilitates the
understanding of multi-tier neighbors. Let's assume that during the
topology discovery, radio node A is discovered by radio nodes B, C
and D. In this case, radio node A is the first-tier scanned
neighbor of radio nodes B, C and D and, by reciprocity, each of the
radio nodes B, C and D are first-tier neighbors of radio node A.
Therefore, first-tier neighbors can be discovered via direct
scanning and/or reciprocity principle as applied to the directly
scanned neighbors. Let's further assume that during the discovery
process, radio node E is discovered by radio node B, radio node F
is discovered by radio node D, and radio node G is discovered by
radio node F. In such a scenario, radio node E is the first-tier
scanned neighbor of radio node B, and a second-tier neighbor of
radio node A. Further, radio node F is a first-tier scanned
neighbor of radio node D, and a second-tier neighbor of radio node
A. Finally, radio node G is a first-tier scanned neighbor of radio
node F, a second-tier neighbor of radio node D, and a third-tier
neighbor of radio node A. A constructed neighbor list for each of
the nodes A through G includes the scanned first-tier neighbors, as
well as any number of multiple tiers of additional neighbors, which
collectively constitute a listing of handoff neighbors for that
particular cell. It should be noted that in FIG. 5, for the sake of
simplicity, the coverage area associated with the nodes are
depicted as non-overlapping hexagonal blocks. However, in practical
scenarios, the coverage areas of the various radio nodes may be
overlapping and/or have different shapes.
[0064] Returning to the block diagram of FIG. 4, after the
completion of internal topology discovery, the appropriate PSCs are
assigned to the discovered internal cells (see step 406 of FIG. 4).
The PSC assignment is designed to minimize the downlink
interference between the radio nodes. The set of assignable PSC's
may be significantly smaller than the number of radio nodes and,
therefore, any assignment scheme must consider the possibility of
considerable re-use of the PSCs. This could be particularly true if
the deployment of the network consists multiple buildings with
different PSCs in use by the neighboring external radio nodes.
Furthermore, wherever possible, it must be ensured that PSC's are
not assigned within two tiers of each other. If this condition is
violated, an access point may end up having two different
first-tier neighbors that use the same PSC. Such a scenario is
likely to cause a number of handoff problems to/from that
particular access point and its neighbors. However, the information
necessary to make the proper PSC assignments are readily available
from the information collected during the above-described external
and internal cell discovery processes.
[0065] According to an example embodiment, PSC's are assigned to
the internal access points according to the following example
hierarchy, proceeding serially in arbitrary order through the
access points:
[0066] (1) A PSC not yet assigned to any access point in the
internal network, and one which is not used in the first- or
second-tier neighbors.
[0067] (2) A PSC assigned to at least one access point in the
internal network, but one which is not used in the first- or
second-tier neighbors. In case of a tie between two or more PSCs,
the PSC that is thus far assigned the fewest number of times to the
internal access points is selected.
[0068] (3) A PSC used in the second-tier neighbors but not used in
the first-tier neighbors. In case of a tie between two or more PSCs
that are used in second-tier neighbors, the PSC that was detected
by a first-tier neighbor with the smallest common pilot channel
(CPICH) RSCP is selected.
[0069] (4) A PSC used in the first-tier neighbors. In case of a tie
between two or more PSCs, the PSC detected with the smallest CPICH
RSCP is selected.
[0070] Step 406 in FIG. 4 can also include assigning transmit power
levels for each of the internal radio nodes. The power level
assignment may be carried out to allow proper operation of the
network based on the desired coverage criteria. Power allocation
may be made and readjusted based on different coverage scenarios
that can occur in the network. For example, a higher power level
may be assigned to a radio node in a part of the network with a
"coverage hole." In contrast, the allocated power may be reduced in
a scenario where the radio node's transmissions are likely to cause
interference with the transmissions of neighboring radio nodes
across an area larger than the intended zone of coverage. The power
levels may further be re-adjusted based on periodic measurements by
one or more UEs that may be carried out on an on-going basis.
[0071] At the end of steps 406, the topology of the network and the
appropriate PSC's associated with each radio node has been
determined with zero, or minimal, manual intervention. More
specifically, the set of internal radio nodes (i.e., radio nodes
within the network), a set of discovered external radio nodes, the
first-tier neighbor relationships between the internal and external
radio nodes, the PSC's assignments to internal radio nodes, the
PSC's associated with external radio nodes, as well as the
appropriate signaling parameters for each internal radio node and
relevant external radio nodes are discovered. By the way of
example, and not by limitation, in a UMTS embodiment, the signaling
parameters include a radio network controller identity (RNCID), a
cell identifier (CID) that identifies a cell within an RNS, a
public land mobile network identification (PLMNID), a channel
number (e.g., UARFCNDL) and the like.
[0072] Next, in step 408 of FIG. 4, the neighbor list for each
radio node is constructed. Such a constructed neighbor can include
a listing of all cells that are candidates for a handoff operation
(i.e., a listing of all handoff neighbors). An entry in such a
constructed neighbor list includes all relevant discovered
information to enable soft handoff and/or hard handoff to the
listed radio node. An entry in the neighbor list can include an
identification that designates the radio node as an internal or
external node, various signaling parameters, such as RNCID, CID,
PLMNID, channel number, PSC, etc. In one example embodiment, the
constructed neighbor list only includes the information associated
with the first-tier scanned neighbors of a radio node. In another
example, the constructed neighbor list includes the first N tiers
of neighbors of a radio node. As noted earlier, the multiple tiers
of neighbors may have been detected by one or more neighboring
radio nodes. The size of the constructed neighbor list may be
limited arbitrarily or by an implied limit of the wireless
air-interface. For example, the UMTS R99 through REL6 limits the
number of intra-frequency cell handles in the CELL_INFO_LIST to a
maximum of 32, the number of inter-frequency cell handles in the
CELL_INFO_LIST to a maximum of 32, and the number of inter-RAT cell
handles in the CELL_INFO_LIST to a maximum of 32. In each of the
above UMTS categories, the selection of the 32 cell handles can be
decided based on several factors. By the way of example, and not by
limitation, these factors include the tier numbers of the
neighbors, the measured signal strengths of the neighbors obtained
during the topology discovery phase and the classification of the
neighbors as either internal or external.
[0073] In step 410 of FIG. 4, the constructed neighbor list (or
portions thereof) may optionally be broadcast by each radio node.
In one example that is applicable to UMTS, all or portions of the
contents of the constructed neighbor list is broadcast using SIB11,
SIB11bis, and/or SIB12. In this example, the SIB's may also include
measurement reporting criteria for the user equipment that receive
the broadcast information. The constructed neighbor list (or
portions thereof) that is broadcast by the radio node can become
the intra-frequency, inter-frequency, and inter-RAT portions of the
CELL_INFO_LISTs for user equipment before, and when, the user
equipment first connect to the network. Specifically, the
information that is broadcast in step 410 instructs the user
equipment as to which other cells to look for and under what
measured RF conditions to send various Measurement Report Messages
to the system. It should be noted that while the above examples
associated with step 410 are described in the context of UMTS, the
broadcast of constructed neighbor list can be carried out in
systems that employ other technologies, such as GSM, EDGE, CDMA2000
and the like.
[0074] In step 412 of FIG. 4, the constructed neighbor list (or
portions thereof) is transmitted to each user equipment by a radio
node, once the user equipment connects to the system. Step 412 can
be carried out instead of, or in addition, to step 410 of FIG. 4.
In one example that is applicable to UMTS, the constructed neighbor
list (or portions thereof) is transmitted to the user equipment in
step 412 using one or more Measurement Control Messages. If step
410 were never carried out, the information received by the user
equipment in step 412 would provide the necessary information
related to the neighbors and the associated signaling parameters.
If, on the other hand, the broadcast information in step 410 were
sent, the information received by the user equipment in step 412
would modify or replace the relevant information for the user
equipment. It should be noted again that while the above examples
associated with step 412 are described in the context of UMTS, the
transmission of the constructed neighbor list to the user equipment
can be carried out in systems that employ other technologies, such
as GSM, EDGE, CDMA2000, LTE and the like. At the completion of
steps 410 and/or 412, each user equipment has been instructed by
the network as to which radio nodes to measure (based on the
received PSC) and under what measured conditions to send various
Measurement Report Messages to the system. The set of radio nodes
to measure reflects the neighbor list constructed in 408. It should
be also noted that steps 410 and 412 are included, in-part, to
allow faster measurements of the PSCs. However, in some
embodiments, both steps 410 and 412 can be omitted. In these
embodiments, the neighbor list is not transmitted to the user
equipment at all. Therefore, the user equipment conducts
measurements associated with the PSC's all on its own and reports
the measured results to the network.
[0075] Based on the instructions from steps 410 and/or 412 of FIG.
4, the user equipment can conduct the appropriate RF measurements
and transmit one or a number of measurement reports over the air to
the radio node. In step 414 of FIG. 4, the measurement reports are
received from one of more user equipment. In one example related to
UMTS, the measurement reports are sent using UMTS Measurement
Report Messages that include, among other items, the type of
measurement report (e.g., Event 1A/B/C/D, Event 2B/D/F, etc.), the
relevant PSC's and the measured RF signal strengths.
[0076] In step 416, based on the information received from the user
equipment, the internal and external radio nodes are mapped to
facilitate handoff operations to/from the appropriate internal or
external cells. The following example illustrates some of the
operations that may be carried out in step 416. Let's assume that a
user equipment has a current Serving Cell X and other cells, Y and
Z, in its Active Set. Let's further assume that the user equipment
sends a measurement report indicating PSC A is measured with some
strength. The controller may then examine the constructed neighbor
list associated with cell X, and perhaps with cells Y and Z, to
locate a neighbor of cell X (and perhaps Y and Z) with PSC A. If a
neighbor cell (e.g. Cell W) with PSC A is listed in one of the
constructed neighbor lists, then the controller associates/maps the
user equipment's measurement of PSC A with that of cell W. If, on
the other hand, a neighbor cell with PSC A is not found within the
constructed neighbor list(s), the measurement information
associated with the received PSC A can be compared against the
information associated with the PSCs on the constructed neighbor
list in order to validate the status of existing neighbors and/or
to update the neighbor list. For example, a radio node may be added
to, or deleted from, a user equipment's Active Set, or a user
equipment's Best Cell and/or Serving Cell may be modified. In one
scenario in the context of the above noted example, a cell within
the system with PSC A may be added to the neighbor list of Cell X.
In one embodiment, when the PSCs that are received from the user
equipment are mapped to internal radio nodes, the corresponding
radio nodes are considered candidates for a soft handoff
operations. In another embodiment, when the reported PSCs are
mapped to external radio nodes, the corresponding radio nodes are
considered for hard handoff operations to an adjacent network.
[0077] Steps 408 to 416 facilitate handoff operations of the user
equipment for at least the reasons that follow. Cells are
internally represented by a unique internal cell handle, or by the
unique pair (RNC ID, CID). Communications that are conducted with
the core network are carried out using the unique identifier (RNC
ID, CID, etc.). However, the user equipment measurements are
reported over the air interface with the associated PSCs. These
PSCs may be reused throughout the internal network, reused many
times throughout the macro network, reused between different
enterprise networks, and may be reused between the enterprise
network and the macro network. The operations that are conducted in
steps 408 through 416 facilitate at least the mapping of the
reported PSCs to particular internal or external cell identities
(e.g., the PSC is associated with particular RNCID and/or CID of
the cells). Further, in embodiments that utilize steps 408 and 412,
the user equipment can conduct rapid measurements of the particular
PSC's of interest around a serving cell.
[0078] The operations of steps 410 through 416 further enhance the
utility of the constructed neighbor lists by enabling the inclusion
of additional cells (i.e., with particular PSCs that are discovered
through the measurement reporting process) on the constructed
neighbor lists. In one example, when a new PSC is discovered, the
most likely "other" cell in the system with that particular PSC can
be selected and added to the constructed neighbor list. In other
embodiments, the measurement reports of step 414 can facilitate the
removal of cells from the constructed neighbor lists. For example,
over time, the system can learn that a particular PSC is not being
reported by any user equipment. In such a scenario, the cell
associated with that PSC can be removed from the constructed
neighbor list. In another example, the system may discover that
when a particular cell is added to the Active Set of a user
equipment which is in a particular cell, the new radio link is
usually or always unreliable or inoperable. In this scenario, that
radio node may be removed from the constructed neighbor list.
[0079] It should also be noted that the information contained in
the measurement reports that are received at step 414 can also
facilitate handoff operations in other ways. For example, a user
that is in cell A may report the detection of intra-frequency cells
C and D in its measurement report, both with similar signal
strengths. In a scenario where C is an internal cell and D is an
external cell, the system may choose to effect a soft-handover to
cell C rather than a hard handover to cell D to minimize the impact
on system operations.
[0080] As described in connection with step 402 of FIG. 4, one
feature of the disclosed embodiments relates to discovering
external cells. The following provides an example procedure for
making such discovery that utilized a central controller. However,
it is entirely possible to effect this and other disclosed
embodiments using a network topology that comprises merely of peer
access points, and/or one or more controllers that reside within
one or more access points. FIG. 6 illustrates a flow diagram for
performing external cell discovery in accordance with an example
embodiment. In step 602, all access points are placed in monitoring
mode at the same time. While in monitoring mode, the access point
monitors and collects information on signals sent to and/or
transmitted by, one or more access points, e.g., access points that
are in operational mode of communication. Since all internal access
points are intentionally placed in the monitoring mode, all
incoming information collected by the internal access points thus
correspond to the access points from external networks.
[0081] In step 604, each access point (that is now in monitoring
mode) performs an RF scan that returns detected PSCs and the
associated measured signal strengths that are detectable from
external networks. This information is received at the controller.
In step 606, the controller transmits a command to each access
point to successively lock onto each of the detected PSCs and
decode the broadcast channel (BCH) of the detected external cell.
In an alternate embodiment, the controller does not have to
transmit a command to each access point for BCH decoding, but
rather each access point autonomously decodes the BCH for any
detected PSC. BCH decoding is done in parallel by each of the
access points within the internal network. In one example
embodiment, instead of allowing all access points to simultaneously
perform the decoding, the decoding process may be throttled by
allowing only up to N access points to work in parallel.
[0082] In an example embodiment, the BCH decode process may be
bypassed by having a user/operator provision a set of external
cells and their signaling parameters comprising their identities.
For example, if each external cell is assumed to have a unique PSC,
then this provisioning may be carried out by (a) listing each
external cell as a neighbor of every internal cell, or (b)
configuring each internal cell to only perform the PSC detection
and measurement to discover the neighboring external cells and
their (measured) signal strengths.
[0083] Referring back to FIG. 6, in step 608, the controller
collects the decoded information obtained from the various access
points. In step 610, it is determined if all the needed information
has been collected for all external cells that were detected by at
least one access point or their attempts to do so have resulted in
a time-out failure. If neither of the two conditions are satisfied,
the process returns to step 608, otherwise, in step 612, system
information is updated. The update may comprise adding the detected
external cells to the relevant neighbor lists of the individual
internal cells. At the end of this process, information relevant to
hand-in and hand-out between internal cells and external cells is
available and the measured signal strengths of each external
neighbor for each access point are also known.
[0084] FIG. 7 is another flow chart that illustrates a set of
exemplary steps that may be carried out by each access point in
response to the command issued in step 606 of FIG. 6. In step 702,
BCH decoding is conducted until at least a unique set of
identifiers is determined from that broadcast channel. For example,
for each known channel frequency and a particular PSC, a unique
identifier comprising a radio network controller identification
(RNC ID) and a cell identification (CID) may be obtained. In step
704, it is determined if another access point has already decoded
the remaining broadcast information associated with this particular
RNC ID and CID. If the information has already been decoded, in
step 706, BCH decoding stops. If, on the other hand, the necessary
information has not been decoded by other access points, the
process is directed to step 708, where BCH decoding continues until
all needed information is decoded. For example, the needed
information may comprise Public Land Mobile Network Identification
(PLMN ID), primary common transmit channel (PCPICH), transmit power
and neighbor PSCs in use. In step 710, it is determined if all the
needed information is decoded or a time-out condition has occurred.
If the answer is yes to either of the above condition, the process
is terminated in step 706, otherwise, the process returns to step
708 to continue with the BCH decoding.
[0085] As noted in connection with step 406 of FIG. 4, a feature of
the disclosed embodiments relates to determining transmit power
levels for each internal cell. FIG. 8 is a block diagram for
determining transmit power levels for internal cells according to
an example embodiment. In step 802, all access points within the
internal network are configured to operate in the operational mode
with either a default power assignment or one based on the
measurements obtained during the external and internal discovery
processes. In step 804, a list of user equipment identification
information, such as a list of International Mobile Subscriber
Identities (IMSIs), is configured in the system. The list may be
empty (i.e., with no IMSI's) or may include a wildcard (i.e., all
IMSI's). In step 806, an installer connects to the network using a
UE with an IMSI that was included on the above-noted list.
[0086] In step 808 of FIG. 8, measurement commands are sent to the
UE with the listed IMSI. The measurement commands instruct the UE
to send periodic measurement reports. The measurements may include
information related to measured CPICH RSCP and/or CPICH Ec/No
(i.e., the received energy per chip divided by the power density in
the band) corresponding to a particular set of cells and their
PSCs. These cells are typically the first-tier and possibly the
second-tier neighbor cells in both the internal and external
networks. The measurement commands that are issued to the UE in
step 808 instruct the UE to provide periodic measurement reports.
Thus, unlike some event-based reports that are typically designed
for handoff and active cell maintenance, periodic measurement
reporting ensures a continuous sampling of the RF environment. In
step 810, the installer physically walks around the deployment area
carrying the UE, which is now configured to send periodic
measurement reports to the controller. According to an alternate
embodiment of the present invention, the installation walk-through
is optional. Instead, the measurement results and the corresponding
power adjustments are carried out over time based on measurement
reports from true users. For example, in one embodiment, the subset
of users chosen for periodic reporting may be chosen to maximize
coverage across the network. In a similar, but distinct embodiment,
the subset of users chosen for periodic reporting may be varied
dynamically in time to maximize the battery life of the user
terminals, and to prevent undue battery drain on a small subset of
users.
[0087] In step 812 of FIG. 8, the measurement reports are
optionally filtered to produce a small set of critical measurement
points that represent the most difficult areas of the deployment
area in terms of adequacy of network coverage. It should be noted
that the filtering that is carried out in step 812 may be performed
either before or after the completion of step 814. In step 814, the
installer instructs the system to compute the transmit power
assignment for all the access points within the internal network.
In step 816, the controller applies a power allocation algorithm
based on the UE measurements that have been captured and optionally
filtered. This results in the access points' usage of newly
computed power for CPICH, maximum total power, and possibly other
channel power configurations. In making the above assessments,
coverage target for the deployment of the network may be designed
based on power measurements of the external cells that were carried
out during the external discovery operations. Further, power
assignment may be premised based on an attempt to "cover" every
measurement point using one of more access points.
[0088] Utilizing a central controller to conduct the assignments
allows coordination and allocation of resources as needed. For
example, an area may be covered by possibly selecting a single
access point with the smallest pathloss, a single access point that
does not have the smallest pathloss (e.g., if that access point
needs a high power level to cover a different measurement point),
or multiple access points potentially with a lower coverage target
(e.g., corresponding to soft handoff gains). Further, the
above-noted processes allow automatic identification and
designation of coverage "holes" when an inability to cover a
measurement point is observed. Moreover, the various embodiments of
the present invention may be carried out without the use of central
controller, for example, by a peer group of access points.
[0089] The disclosed embodiments also facilitate the addition of a
cell to an existing network. FIG. 9 is a block diagram that
illustrates the steps for adding a radio node to an existing
network pursuant to an exemplary embodiment. In step 902, the newly
added radio node scans its environment while the rest of the
network is operational. During the scanning process, the newly
added radio node detects PSCs that are in use around its local area
and measures the signal strengths associated with each of the
detected radio nodes. In step 904, the newly added radio node
determines the identity of the detected radio nodes. In one
example, the newly added radio node decodes the broadcast channels
associated with each of its detected radio nodes. In doing so, the
newly added radio node learns the identity of each associated cell
by obtaining parameters such as PSC, RNCID, CID, PLMNID, and the
like.
[0090] In step 906, a first-tier neighbor list for the newly added
radio node is constructed. As part of step 906, based on the
initially known topology and PSC assignments (which were obtained,
for example, through steps 402 to 416 of FIG. 4), as well as the
information obtained from steps 902 and 904, the first-tier
neighbors associated with the newly added radio node are
constructed. The constructed neighbor list includes first-tier
associations between the newly added radio node and all other known
radio nodes in the system (internal and external to the network),
and potentially newly discovered external radio nodes. For example,
a newly discovered radio node can be identified when the newly
added radio node discovers parameters, such a UARFCNDL, PSC, RNCID,
CID, PLMNID, that do not match any of the known radio nodes. As
part of the operations in step 906, a PSC is intelligently assigned
to the newly added radio node. The various considerations for
assigning the PSC were previously discussed in connection with step
406 of FIG. 4. In addition, an appropriate initial transmit power
level can also assigned to the newly added radio node.
[0091] In step 908, the neighbor lists for all radio nodes are
reconstructed. In one embodiment, the reconstruction of step 608 is
carried out by applying RF reciprocity. In this embodiment, it is
assumed that if the newly added radio node detects a radio node as
a first-tier scanned neighbor with a particular signal strength,
then the detected first-tier neighbor would also detect the newly
added radio node with the same signal strength. Therefore, the
newly added radio node is also a first-tier neighbor of all of its
own first-tier scanned neighbors. In another embodiment, upon the
addition of a new radio node, the operations described in FIG. 4
may be repeated to update the neighbor lists for all radio nodes.
Such an approach, while expensive for networks with a large number
of radio nodes, may be feasible in smaller network deployments. In
yet another embodiment, rather than applying reciprocity or
performing a comprehensive scan of the entire network, only the
detected (i.e., scanned) first-tier neighbors of the newly added
radio node are instructed to conduct a scan to determine if the
newly added radio node can be detected. As a part of step 908, or
in a separate step, the multi-tier neighbor lists for all radio
nodes, including the new radio node, is updated to reflect the
presence of the newly added radio node and to include second-,
third- and higher-tier relationships. This additional step is not
required if, as noted above, a comprehensive scan of the entire
network is conducted.
[0092] In step 910 of FIG. 9, the reconstructed neighbor lists may
be broadcast to the entire network. This step is similar to step
410 of FIG. 4. For example, the broadcast SIB11, SIB11bis and/or
SIB12 may be modified based on the updated neighbor lists.
Additionally, or alternatively, updated neighbor lists may be
transmitted to each user equipment in step 912. For example,
Measurement Control Messages (with an updated intra-frequency
CELL_INFO_LIST) may be sent to each connected user equipment. The
operations carried out in step 912 are similar to those in step 412
of FIG. 4. In addition, the connected user equipment may be
requested to measure the PSC assigned to the newly added radio
node. In such a scenario, the measurement reports are received in
step 914, where they can be used to update the mapping of internal
and external radio nodes in step 916. In one example related to
UMTS, Measurement Report Messages are received in step 916. The
integration of the received measurement reports with other
information that facilitate the various handoff operations are
conducted similar to the operations in step 416 of FIG. 4.
[0093] When a radio node is deleted or disabled (rather than
added), the inverse operations may be applied. Specifically, the
deleted or disabled radio nodes are removed from the detected
topology, the neighbor lists are recomputed and updated broadcast
and/or unicast messages are sent to the user equipment to reflect
the new topology.
[0094] The disclosed embodiments can further facilitate hand-in to
a network by an external entity by propagating the relevant
information to the external entity. FIG. 10 is a block diagram that
describes the various operations associated with facilitating
hand-in operations pursuant to an example embodiment. The
operations in FIG. 10 are illustrated from the point of view of an
entity within the internal network. Based on the operations that
were described in connection with FIG. 4, the relevant signaling
and configuration information (e.g., UARFCNDL, PSC, RNCID, CID,
PLMNID, etc.) associated with detected external radio nodes are
known. In step 1002 of FIG. 10, an external radio node is selected.
In step 1004, a neighbor list associated with the selected external
node is created. Such a list, which can be created from the
information obtained as a result of steps 402 to 408 of FIG. 4,
includes all internal radio nodes that detected the external node
as a first-tier neighbor. Such a list can further include second-
and higher-tier neighbors. The neighbor list also includes various
signaling information associated with each of the listed internal
radio nodes. The neighbor list that is created in step 1004, thus,
provides the pertinent information regarding all internal radio
nodes that are considered candidates for a hand-in operation from
the external radio node.
[0095] In one embodiment, the neighbor list that is created in step
1004, can comprise one or more "closest" internal radio nodes to
the external radio node. The closest internal radio node can be
selected based on the internal cell's measured signal strength of
the external cell and/or the number of tiers between the internal
and the external cell. For example, an internal cell that is a
first-tier neighbor of the external cell is considered to be
"closer" than an internal cell that is a second-tier neighbor of
that external cell. As another example, internal cell A that
measures an external cell stronger than internal cell B, is
considered to be "closer" to the external cell than internal cell
B. In yet another embodiment, the neighbor list that is created in
step 1004 can simply include all internal radio nodes known to the
network. In still another embodiment, the first-tier neighbor
relationships can be populated in a data model and queried via a
standard device configuration, such as TR-69 or TR-196.
[0096] After the completion of step 1004, the neighbor list can be
sent to the external entity (see step 1008). However, in one
embodiment, after the completion of step 1004, it is determined, in
step 1006, whether more external radio nodes are recognized by the
network. If the answer is yes, the process returns to step 1002,
where another external radio node is selected and the associated
neighbor list is created. Once all external radio nodes have been
considered, the process continues to step 1008, where the neighbor
lists associated with all recognized external radio nodes are sent
to the external entity. The external entity can then use the
information provided in the neighbor list(s) to select the proper
radio node for conducting a handoff operation.
[0097] FIG. 11 illustrates the operations associated with a hand-in
operation in accordance with an example embodiment. The operations
in FIG. 10 are illustrated from the point of view of an entity
within the external network. In step 1102, the neighbor lists,
which were produced pursuant to the operations of FIG. 10, are
received. In step 1104, the external entity updates the neighbor
lists of the external cells with the received information. In
addition, step 1104 can include operations that are similar to the
procedures described in steps 408 to 416 of FIG. 4. These
operations are not explicitly diagramed in the flow chart of FIG.
11. However, it is understood that some or all of the operations
that are similar to steps 408 to 416 of FIG. 4 can be conducted as
part of step 1104. The updated neighbor lists that are produced in
step 1104 can be used by the external cells to facilitate hand-in
to the internal cell(s). Specifically, each external cell has a
list of cells associated with the internal network and their
associated PSC and identification information (e.g., PSC, RNCID,
CID, PLMNID). A user equipment with an on-going session with an
external network may be a candidate for a hand-in operation to the
internal network.
[0098] At step 1106 of FIG. 11, a measurement report is received
from the user equipment with an on-going session with the external
cell. The measurement report comprises a PSC associated with one of
the cells of the internal network. At step 1108, the external
network maps the reported PSC to the corresponding internal cell
and its associated signaling parameters (e.g., RNC ID, CID,
PLMNID). Next, a hand-out indication is produced at 1110. In one
example, a particular core network message from the external RNC to
the core network provides such an indication from the external
network that includes the associated signaling information. For
instance, such a message can be a UMTS serving radio network
subsystem (SRNS) RELOCATION REQUIRED message that includes the
target internal cell's identification information (e.g., RNC ID,
CID). In this example, the core network, which receives the SRNS
RELOCATION REQUIRED message from the external entity, translates
the message into an SRNS RELOCATION REQUEST message, including the
target internal cell's identification information (e.g., RNC ID,
CID), that is sent to the controller of the internal network. As
such, from the perspective of the internal network (e.g., internal
network's controller' perspective), a "hand-in indication" (e.g.,
in the form of the SRNS RELOCATION REQUEST message) is received.
Although the above example has been described using SRNS RELOCATION
messages, it is to be understood that other messages that convey a
hand-out/hand-in operation can be communicated between the external
and the internal entity.
[0099] Referring back to FIG. 11, at 1112, the external network
commences a hand-in operation from the external network to the cell
within the internal network which was mapped/identified in step
1108. The hand-in operation at step 1112 can be, for example, a
hard hand-in operation.
[0100] As noted earlier, the mapping of the received PSCs to the
internal (or external) cells is done by comparing the newly
detected PSCs with the PSCs that are already recognized by the
system as corresponding to a particular cell (i.e., a particular
RNCID and/or CID). For example, a user equipment's report can
indicate the detection of PSC A at signal strength S.sub.A, PSC B
at strength S.sub.B, and so on. In this scenario, the network can
check the constructed neighbor list of the user equipment's serving
cell in search of an entry with PSC A. If a single match is found,
the detected PSC A is mapped to the cell with the associated RNCID
and/or CID.
[0101] In some embodiments, the above described search operations
can produce no matches in the serving cell's constructed neighbor
list. In such a scenario, the search can be expanded to include the
constructed neighbor lists of the serving cell's neighbors. In
other embodiments, the search operation may produce more than one
match. That is, multiple radio nodes on the constructed neighbor
list may have been assigned to the same PSC. In one embodiment,
when multiple matches are found, the detected PSC can be mapped to
the cell that is "closest" in RF sense to the serving cell of the
user equipment that produced the measurement report. In another
embodiment, when multiple matches are detected, all the reported
PSC's (e.g., PSC A, PSC B, etc.) and their reported signal
strengths (S.sub.A, S.sub.B, etc.) are used to algorithmically
provide a best estimate as to which cell corresponds to the
reported PSC.
[0102] In another embodiment, the detection of multiple PSC matches
are circumvented all together by selectively eliminating multiple
listings of the same PSC on a constructed neighbor list. In one
example, during the construction of a neighbor list, upon finding
multiple listings of the same PSC, only one PSC associated with one
radio node is retained. For instance, the radio node that is
"closest" to the serving cell is selected. In one example, the
lowest tier neighbor cell is selected (e.g., a first-tier neighbor
cell is retained over a second-tier neighbor cell). In the event of
a tie, the cell that is detected with the highest signal strength
is selected.
[0103] While some of the exemplary embodiments have been described
in the context of a self-configuring and self-optimizing wireless
network with multiple radio nodes and one or more central
controllers, it is understood that the disclosed embodiments are
equally applicable to networks without a central controller (e.g.,
an autonomous collection of femtocells). In a de-centralized
network, direct radio node-to-radio node communications (over the
air or through a wired communication link) may be carried out to
conduct the various scans, report measurement results and utilize
the pooled measurement information to construct the neighbor lists.
Similarly, the disclosed embodiments can be applied to hybrid
systems that utilize both a central controller and peer-to-peer
radio node communications.
[0104] These disclosed embodiments can be further extended to a
number of different wireless systems with a hierarchical structure
that include entities that are functionally equivalent to radio
nodes and user equipment. For example, a wireless network where the
radio nodes are placed without extensive planning (e.g., mesh
networks and/or military field networks) can analogously utilize
the disclosed embodiments. In such networks, an installed radio
node scans for its neighbors to discover the local topology,
differentiates between radio nodes that can coordinate in a
cohesive network (i.e., internal radio nodes) against a distinct
network (i.e., external radio nodes), sends the discovered
topological information to one or more user equipment for
conducting measurements, uses the measurement results reported by
the user equipment to correlate measurements at the user equipment
location with the associated topological neighbors, and informs and
enables handoff decisions between a user equipment that is
operating with the radio node to a neighboring radio node.
[0105] The disclosed embodiments that relate to internal topology
discovery and the construction of neighbor lists may further
include features that are based on observations of the user
equipment behavior in the network. For example, let's assume a user
equipment reports a particular PSC in a Measurement Report Message
that is not part of the constructed neighbor list of radio node A.
Let's further assume that the user equipment's session is
subsequently dropped due to bad RF conditions, and that the same
user equipment next reappears at radio node B with the reported
PSC. In such a scenario, the constructed neighbor list of radio
node A can be updated to include radio node B as a neighbor and,
similarly, the constructed neighbor list of radio node B can be
updated to list radio node A as its neighbor. Furthermore, this
modification of neighbor lists may be fed back into the PSC
assignment algorithm to account for the "newly discovered"
topological change when assigning the appropriate PSCs. As such,
the topological map of the network, the neighbor lists and the
associated parameters can be modified based on the behavior of the
user equipment.
[0106] It is understood that the various embodiments of the present
invention may be implemented individually, or collectively, in
devices comprised of various hardware and/or software modules and
components. These devices, for example, may comprise a processor, a
memory unit, an interface that are communicatively connected to
each other, and may range from desktop and/or laptop computers, to
consumer electronic devices such as media players, mobile devices
and the like. For example, FIG. 12 illustrates a block diagram of a
device 1200 within which the various embodiments of the present
invention may be implemented. The device 1200 comprises at least
one processor 1202 and/or controller, at least one memory 1204 unit
that is in communication with the processor 1202, and at least one
communication unit 1206 that enables the exchange of data and
information, directly or indirectly, with other entities, devices
and networks 1208a to 1208f. For example, the device 1200 may be in
communication with mobile devices 1208a, 1208b, 1208c, with a
database 1208d, a sever 1208e and a radio node 1208f. The
communication unit 1206 may provide wired and/or wireless
communication capabilities, through communication link 1210, in
accordance with one or more communication protocols and, therefore,
it may comprise the proper transmitter/receiver antennas, circuitry
and ports, as well as the encoding/decoding capabilities that may
be necessary for proper transmission and/or reception of data and
other information. The exemplary device 1200 that is depicted in
FIG. 12 may be integrated as part of the various entities that are
depicted in FIGS. 1-3, including an access controller 114, an
access point 101, 102, 104, 106, 108 and 112, a radio node
controller 204a and 204b, a Node B 206a and 206b, a user equipment
208a, 208b and 208c, a services node 304 and/or a radio node 306a,
306b and 306c. The device 1200 that is depicted in FIG. 12 may
reside as a separate component within or outside the above-noted
entities that are depicted in FIGS. 1-3.
[0107] The various components or sub-components within each module
of the disclosed embodiments may be implemented in software,
hardware, firmware. The connectivity between the modules and/or
components within the modules may be provided using any one of the
connectivity methods and media that is known in the art, including,
but not limited to, communications over the Internet, wired, or
wireless networks using the appropriate protocols.
[0108] Various embodiments described herein are described in the
general context of methods or processes, such as the processes
described in FIGS. 4 and 6 through 11 of the present application.
It should be noted that processes that are described in FIGS. 4 and
6 through 11 may comprise additional or fewer steps. For example,
two or more steps may be combined together. The disclosed methods
may be implemented in one embodiment by a computer program product,
embodied in a computer-readable medium, including
computer-executable instructions, such as program code, executed by
computers in networked environments. A computer-readable medium may
include removable and non-removable storage devices including, but
not limited to, Read Only Memory (ROM), Random Access Memory (RAM),
compact discs (CDs), digital versatile discs (DVD), etc. Therefore,
the disclosed embodiments can be implemented as computer program
products that reside on a non-transitory computer-readable medium.
Generally, program modules may include routines, programs, objects,
components, data structures, etc. that perform particular tasks or
implement particular abstract data types. Computer-executable
instructions, associated data structures, and program modules
represent examples of program code for executing steps of the
methods disclosed herein. The particular sequence of such
executable instructions or associated data structures represents
examples of corresponding acts for implementing the functions
described in such steps or processes.
[0109] The foregoing description of embodiments has been presented
for purposes of illustration and description. The foregoing
description is not intended to be exhaustive or to limit
embodiments of the present invention to the precise form disclosed,
and modifications and variations are possible in light of the above
teachings or may be acquired from practice of various embodiments.
For example, the disclosed embodiments are equally applicable to
networks that utilize different communication technologies,
including but not limited to UMTS (including R99 and all high-speed
packet access (HSPA) variants), as well as LTE, WiMAX, GSM and the
like. The embodiments discussed herein were chosen and described in
order to explain the principles and the nature of various
embodiments and its practical application to enable one skilled in
the art to utilize the present invention in various embodiments and
with various modifications as are suited to the particular use
contemplated. The features of the embodiments described herein may
be combined in all possible combinations of methods, apparatus,
modules, systems, and computer program products.
* * * * *