U.S. patent application number 11/876019 was filed with the patent office on 2008-02-14 for system and method for servicing communications using both fixed and mobile wireless networks.
Invention is credited to Paul Morton.
Application Number | 20080037493 11/876019 |
Document ID | / |
Family ID | 34376733 |
Filed Date | 2008-02-14 |
United States Patent
Application |
20080037493 |
Kind Code |
A1 |
Morton; Paul |
February 14, 2008 |
SYSTEM AND METHOD FOR SERVICING COMMUNICATIONS USING BOTH FIXED AND
MOBILE WIRELESS NETWORKS
Abstract
Mobile wireless device(s) roam within and between premises and a
vehicle or other mobile platform and interface to wireless local
area networks within the premises or vehicle. When using the
intra-vehicular network, a communication relay within the vehicle
routes communications from the wireless device to a wide area
wireless network such as cellular network or satellite network.
This allows the power consumption of the mobile wireless device to
be greatly reduced as the mobile device need only communicate with
the local intra-vehicular WLAN. The vehicle acts as the power
supply for the relay. When the coverage area of the intra-vehicular
WLAN overlaps that of another WLAN, seamless handoff allows
continuous data or voice connectivity between the overlapping
wireless networks.
Inventors: |
Morton; Paul; (Vancouver,
CA) |
Correspondence
Address: |
GARLICK HARRISON & MARKISON
P.O. BOX 160727
AUSTIN
TX
78716-0727
US
|
Family ID: |
34376733 |
Appl. No.: |
11/876019 |
Filed: |
October 22, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10673876 |
Sep 29, 2003 |
|
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11876019 |
Oct 22, 2007 |
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Current U.S.
Class: |
370/338 |
Current CPC
Class: |
H04M 1/72412 20210101;
H04W 92/02 20130101; H04W 52/0229 20130101; H04W 88/04 20130101;
H04W 88/06 20130101; H04W 84/12 20130101; H04M 2250/02 20130101;
Y02D 30/70 20200801; H04W 52/0274 20130101; H04W 88/16
20130101 |
Class at
Publication: |
370/338 |
International
Class: |
H04Q 7/24 20060101
H04Q007/24 |
Claims
1. A method to service communications with a mobile wireless
devices, comprising: establishing a communication pathway between
the mobile wireless device and a premises based wireless network,
wherein the communication pathway allows the mobile wireless device
to communicate with resources available through the premises based
wireless network; moving the mobile wireless device to an area
wherein coverage of the premises based wireless network overlaps an
intra-vehicular wireless network; establishing a parallel
communication pathways that comprise: a first communication path
between the mobile wireless device and the premises based wireless
network; and a second communication path between the mobile
wireless device and an extravehicular wireless network via a
vehicular wireless interface, a vehicular mountable relay, and an
extra-vehicular wireless interface; and handing the wireless device
from the premises based wireless network to the intra-vehicular
wireless network, wherein the parallel communication pathways
allows continuous communications between the mobile wireless device
and the resources.
2. The method of claim 33, wherein the premises based wireless
network and the vehicular wireless network are short-range digital
radio networks and wherein the parallel communication pathway is a
cellular network.
3. The method of claim 33, wherein establishing a parallel
communication pathway further comprises: communicating with the
mobile wireless device via a vehicular wireless interface operable
to communicate with the mobile wireless device over the vehicular
wireless network; and relaying communications between the mobile
wireless device and the resources from the vehicular wireless
interface, through a mobile network relay, and to an extravehicular
wireless interface operable to establish a communication pathway
with an external network.
4. The method of claim 35, wherein the mobile wireless device is a
telephone hand set.
5. The method of claim 35, wherein the mobile wireless device is a
Personal Data Assistant or computing device.
6. The method of claim 35, further comprising servicing handoff
from a first premises based wireless network to a cellular network
to a second premises based wireless network.
7. The method of claim 38, wherein the first premises based
wireless network and the second premises based wireless networks
have non-contiguous service coverage areas.
8. The method of claim 33, wherein the extravehicular wireless
network is a satellite based wireless communication network.
9. The method of claim 33, further comprising determining
capabilities of the mobile wireless device.
10. The method of claim 41, further comprising making handoff
decisions based upon the mobile wireless device.
11. The method of claim 42, wherein the mobile wireless device has
Bluetooth.RTM., 802.11, and/or cellular interfaces.
12. The method of claim 43, further comprising directing that the
mobile wireless device be serviced according to a comparison of a
cellular connection though the mobile wireless device's cellular
interface's quality of signal and the quality of signal of a
communication pathway through the extravehicular wireless
network.
13. The method of claim 43, further comprising directing that the
mobile wireless device be serviced by the Bluetooth.RTM., 802.11,
or cellular interfaces based on power consumption associated with
the Bluetooth.RTM., 802.11, and cellular interfaces.
14. The method of claim 43, further comprising initiating handoff
to the extravehicular wireless network when the signal strength
compares unfavorably to a handoff threshold.
15. The method of claim 33, further comprising registering the
mobile wireless device with the vehicular wireless network.
16. A method to service communications with a mobile wireless
devices, comprising: establishing a communication pathway between
the mobile wireless device and a second extravehicular wireless
network, wherein the communication pathway allows the mobile
wireless device to communicate with resources available through the
second extravehicular wireless network; moving the mobile wireless
device to an area wherein coverage of the second extravehicular
wireless network overlaps an intra-vehicular wireless network;
establishing a parallel communication pathways that comprise: a
first communication path between the mobile wireless device and the
second extravehicular wireless network; and a second communication
path between the mobile wireless device and an first extravehicular
wireless network via a vehicular wireless interface, a vehicular
mountable relay, and an extra-vehicular wireless interface; and
handing the wireless device from the second extravehicular wireless
network to the intra-vehicular wireless network, wherein the
parallel communication pathways allows continuous communications
between the mobile wireless device and the resources, and wherein
the first communication path is terminated after a favorable
handoff.
17. The method of claim 16, wherein the premises based wireless
network and the vehicular wireless network are short-range digital
radio networks and wherein the parallel communication pathway is a
cellular network.
18. The method of claim 16, wherein establishing a parallel
communication pathway further comprises: communicating with the
mobile wireless device via a vehicular wireless interface operable
to communicate with the mobile wireless device over the vehicular
wireless network; and relaying communications between the mobile
wireless device and the resources from the vehicular wireless
interface, through a mobile network relay, and to an extravehicular
wireless interface operable to establish a communication pathway
with an external network.
19. The method of claim 18, further comprising servicing handoff
from a first premises based wireless network to a cellular network
to a second premises based wireless network.
20. A mobile network relay device mounted within a vehicle the
mobile network relay device operable to facilitate a wireless
device handoff that includes existing wireless communications,
wherein the handoff of the wireless device and existing
communications occurs between an intra-vehicular wireless network
and a first extravehicular wireless network, comprising: a first
wireless interface operable to communicate with a wireless device
over an intra-vehicular wireless network, wherein the
intra-vehicular wireless network is a short-range digital radio
network, the wireless device operable to communicate through a
second extravehicular wireless network; a second wireless interface
operable to establish an communication pathway with an first
extravehicular wireless network, wherein the first extravehicular
wireless network is a cellular network or a satellite based
network; and a vehicular mountable relay that communicatively
couples the first wireless interface and the second wireless
interface and that routes communications between the wireless
device and the first extravehicular wireless network wherein a
coverage area of the intra-vehicular wireless network overlaps with
a coverage area of the second extravehicular wireless network; and
the vehicular mountable relay controls and services the wireless
device handoff between the second extravehicular wireless network
and the first extravehicular wireless network, and wherein a prior
communication path is terminated after a favorable handoff to a new
communication path.
Description
RELATED APPLICATIONS
[0001] This application claims priority to and is a continuation of
U.S. patent application Ser. No. 10/673,876, entitled "SYSTEM AND
METHOD FOR SERVICING COMMUNICATIONs USING BOTH FIXED AND MOBILE
WIRELESS NETWORKS," filed Sep. 29, 2003, which is incorporated
herein by reference for all purposes.
TECHNICAL FIELD
[0002] The present invention relates generally to mobile wireless
devices, and more particularly to a mobile network relay device
that allows wireless communication devices adapted to a first local
wireless network to interface with a second wireless network.
BACKGROUND OF THE INVENTION
[0003] Communication technologies that network electronic devices
are well known. Examples of those technologies include: wired
packet data networks; wireless packet data networks; wired
telephone networks; and satellite communication networks, among
others. These communication networks typically include a network
infrastructure that services a plurality of client devices. The
Public Switched Telephone Network (PSTN) is probably the best-known
communication network and has been in existence for many years. The
Internet, another well-known example of a communication network,
has also been in existence for a number of years. Communication
networks like these enable client devices to communicate with one
another on a global basis.
[0004] Local Area Networks (wired LANs), e.g., Ethernets, support
communications between networked computers and other devices within
a serviced area. These wired LANs often link serviced devices to
Wide Area Networks (WANs) such as the Internet. Each of these
networks is generally considered a "wired" network, even though
some of these networks, e.g., the PSTN, may include some
transmission paths that are serviced by wireless links.
[0005] More recently, wireless networks have come into existence.
Examples include cellular telephone networks, wireless LANs
(WLANs), and satellite communication networks. Common forms of
WLANs include Bluetooth.RTM. and IEEE 802.11(a) networks, IEEE
802.11(b) networks, and IEEE 802.11(g) networks some of these
networks are referred to jointly as "IEEE 802.11 networks." In a
typical IEEE 802.11 network, a wired backbone couples to a
plurality of Wireless Access Points (APs), each of which supports
wireless communications with computers and other wireless terminals
that include compatible wireless interfaces within a serviced area.
The wired backbone couples the APs of the IEEE 802.11 network to
other networks, both wired and wireless, and allows serviced
wireless terminals to communicate with devices external to the IEEE
802.11 network. Devices that operate consistently with an IEEE
802.11 protocol may also support ad-hoc networking in which
wireless terminals communicates directly to one another without the
presence of an AP.
[0006] Bluetooth.RTM. enabled wireless devices allow mobile devices
having both low cost and low power consumption. However, these
devices cannot use the Bluetooth.RTM. protocol to access network
resources in a mobile environment that extends beyond the short
range of their digital radio systems. Thus, most mobile systems
rely on wider range cell networks that consume far more power than
Bluetooth.RTM. systems. This higher level of power consumption
reduces the usefulness of these devices by negatively impacting the
battery life of the device.
[0007] WLANs can support both voice and data communications via
wireless terminals. When supporting voice communications, these
wireless terminals often interface with the PSTN through the WLAN.
The communications are routed between the PSTN or other WAN and a
serviced wireless terminal via a WLAN interfaced to a PBX other
like device. Those wireless voice terminals may roam anywhere
within the service area of the WLAN and receive voice service.
However, should the wireless terminal roam outside of the service
area of the WLAN, the call will be dropped. Thus, a need exists for
those wireless terminals to roam and be handed off to and serviced
outside of the coverage area of the WLAN.
SUMMARY OF INVENTION
[0008] This disclosure teaches mobile device(s) that may be located
within a vehicle or other mobile platform. The mobile devices
interface to a mobile wireless network within the vehicle. A relay
routes communications from the mobile device to a wide area
wireless network such as cellular network or satellite network.
This allows the power consumption of the mobile device to be
greatly reduced as the mobile device need only communicate with the
local intra-vehicular WLAN. The vehicle services as the power
supply for the relay.
[0009] When the coverage area of the intra-vehicular WLAN overlaps
that of another WLAN, a seamless handoff allows continuous data or
voice connectivity between the overlapping wireless networks. Thus,
a Bluetooth.RTM. equipped voice handset phone can safely range
between a premises-based network(s) and mobile vehicle network(s)
without negatively impacting data connectivity.
[0010] This disclosure more specifically teaches that
Bluetooth.RTM. enabled wireless devices may roam between WLANs that
support Bluetooth.RTM. voice and/or data communications by
establishing parallel communication pathways between the
Bluetooth.RTM. enabled wireless terminal and overlapping
Bluetooth.RTM. enabled WLANs. In one example, a first WLAN is fixed
to a physical location while a second WLAN has mobile APs. The
second WLAN communicatively couples to a WAN such as a cellular
satellite network. Parallel communications are established, and
handoff criteria govern seamlessly switching communications between
the WLANs in order to avoid any lost or dropped communications.
[0011] Another embodiment provides the mobile network relay device
itself. This mobile network relay device has a first wireless
interface operable to communicate with the wireless device over an
intra-vehicular WLAN. A second wireless interface communicatively
couples to an extravehicular wireless network. The mobile network
relay device routes communications between the first wireless
interface and the second wireless interface and thus between the
wireless device and the extravehicular wireless WAN. This
arrangement allows the power consumption requirements of the
wireless device to be reduced as this burden shifts to the mobile
network relay. The intra-vehicular WLAN is typically a low-power,
short-range, digital radio network such as Bluetooth.RTM. or
another like network. The extravehicular network(s) typically are
cellular, satellite, or other like network(s) known to those
skilled in the art.
[0012] Additionally, parallel pathways allow wireless device(s) to
roam between dynamically overlapping coverage areas of the
intra-vehicular wireless network and premises based WLANs.
[0013] Processors, within either the vehicular mountable relay or
wireless device itself, govern which network services the
communications and the handoff of the wireless device between
premises based WLANs and intra-vehicular WLANs serviced by
extravehicular WANs. During handoff, parallel communication paths
service the wireless device. These parallel communication paths
include: (1) the wireless device to the premises based wireless
network; and (2) the wireless device to the extra-vehicular
wireless network via the first intra-vehicular wireless interface,
the vehicular mountable relay, and the second extravehicular
wireless interface.
[0014] As previously stated, the wireless device(s) may handle
voice, data, or video communications. Thus, the wireless device may
take the form of a telephone handset, camera, mobile computing
device, personal data assistant, laptop computer, or other like
device known to those skilled in the art.
[0015] Additionally, the wireless device may have the internal
ability to communicate over Bluetooth.RTM., 802.11, cellular,
satellite or other like networks. Here, internal processors choose
which network is to be used to balance the signal quality,
transmission cost, and power consumption. Furthermore, these
internal or external abilities, when coupled to a mobile relay,
allow the mobile device to range between a first premises based
WLAN and a second premises based WLAN that have non-contiguous
service coverage areas.
[0016] To simplify the construction of the wireless device, the
decision making process may be executed by processors within the
mobile network relay device. In one example, a cellular connection
though the wireless devices' cellular interface has a first quality
of signal. A communication pathway through the extravehicular
network wireless has a second quality of signal. The processor
directs that communications of the wireless device be serviced by
the cellular connection or extravehicular wireless network after
comparing the first quality of signal and the second quality of
signal. Alternatively, the handoffs may be initiated after
comparing the signal strength of the premises based WLAN and the
extravehicular WLAN.
[0017] To limit the number of wireless devices attempting to
communicate through the mobile network relay device, the wireless
device may be required to register with the module network relay
device. Communications from unregistered wireless devices may be
ignored. Mobile network relay device may be mounted within a
vehicle, such as a plane, train, boat or automobile.
[0018] Another embodiment provides a method of servicing
communications to mobile wireless device(s). First, a communication
pathway between the mobile wireless device and a premises based
wireless network is established. This communication pathway allows
the mobile wireless device to communicate with resources available
through the premises based wireless network. These communications
may convey images, voice, or data communications. The mobile
wireless device may be repositioned to an area wherein coverage of
the premises based wireless network overlaps that of an
intra-vehicular wireless network.
[0019] Parallel communication pathways to the wireless device allow
communications to be routed between the mobile wireless device and
the premises based wireless network, or the mobile wireless device
and an extravehicular wireless network via a vehicular wireless
interface, a vehicular mountable relay, and an extra-vehicular
wireless interface. Handoffs of servicing the wireless device occur
between the premises based wireless network(s) and the
intra-vehicular wireless network based on predetermined criteria.
Continuous communications are maintained between the mobile
wireless device and the resources ensuring that no losses of data
or dropped calls are experienced.
[0020] This decision making process may direct how the mobile
wireless device be serviced after comparing the WLAN(s) and other
connection to the mobile wireless device's quality of signal and
the quality of signal of a communication pathway through the
extravehicular wireless network. Other factors such as cost and
network traffic may be factored into this decision making
process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] For a more complete understanding of the present invention
and the advantages thereof, reference is now made to the following
description taken in conjunction with the accompanying drawings in
which like reference numerals indicate like features and
wherein:
[0022] FIGS. 1A-1D provide is a system diagram illustrating a
premises and mobile Wireless Local Area Network (WLAN) deployed to
service wireless devices;
[0023] FIG. 2 illustrates a network connection servicing the
wireless communications;
[0024] FIG. 3 is a partial system diagram of a WLAN and a cellular
network;
[0025] FIG. 4A-4F provide diagrams illustrating the embodiments of
wireless devices;
[0026] FIG. 5 provides a flow chart illustrating incoming call
operations according to the present invention.
[0027] FIG. 6 is a flow chart illustrating outgoing call
operations; and
[0028] FIG. 7 provides a flow chart illustrating handoff operations
according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] Preferred embodiments of the present invention are
illustrated in the FIGs, like numerals being used to refer to like
and corresponding parts of the various drawings.
[0030] FIG. 1A provides a system overview in which WLANs serve
fixed locations, such as those tied to building 102 and building
104, and mobile locations such as vehicle 106. Building 102 has at
least one Wireless Access Point (AP) 108 which enables Personal
Data Assistants (PDAs), telephone handsets, laptops, mobile
computing devices and other wireless devices to interface with WLAN
110. This WLAN may connect to Wide Area Network (WAN) 112 such as
the Internet or other like WANs known to those skilled in the art.
Similarly, building 104 has AP 114 used to serve wireless devices
within coverage area 116. As shown in callout 118, a wireless AP
120 within vehicle 106 may serve wireless handset 122, PDA 124,
laptop 126 or other wireless devices as known to those skilled in
the art. The coverage area of WLAN 128 serviced by AP 120, as shown
in FIG. 1A, overlaps the coverage area of WLAN 110. Directional
arrow 133 shows that vehicle 106 may travel between various
WLANs.
[0031] WLAN 110 may service wireless handset 122, initially located
within WLAN 110, initially. A user carrying and communicating via
wireless handset 122 may leave building 102 to travel to vehicle
106. As the user and wireless handset 122 leave building 102, they
enter an overlapping coverage area of WLAN 128 tied to vehicle 106.
When this occurs, the handset's communications will be serviced in
parallel with and then handed off to WLAN 128, which is tied to
vehicle 106, in favor of WLAN 110. To maintain a continuous
connection with WAN 112, communications from handset 122 are routed
in parallel through WLAN 110 and WLAN 128. In the case of WLAN 128,
AP 120 within vehicle 106 routes the communications to RF Interface
130 for servicing through a Satellite communications system 132,
Cellular Communications System 134, or other like network. When
serviced by the cellular network, received communications travel
between RF Interface 130 and Base Station 134. This communication
is then routed through the Cellular Infrastructure 136 to its
intended destination over WAN 112. WAN 112 may be the Internet, the
PSTN, or other like network known to those skilled in the art.
Similarly, when RF Interface 130 communicates with Satellite 132,
receiving station 135 and satellite infrastructure 137 deliver
communications via the satellite to WAN 112 as shown in FIG.
1B.
[0032] This disclosure teaches that wireless devices, such as
handset 122, computing device 126 or PDA 124 may communicate with
the WAN through mobile AP 120 and RF Interface 130. This allows the
power consumption of the wireless device to be greatly reduced when
communications are routed through AP 120 and RF Interface 130.
Power consumption is reduced and battery life extended by allowing
the wireless device to maximize its use of low power, short-range,
digital radio. Communication with alternative networks, such as
cellular network 134 or satellite network 132, requires more power
and is executed by the vehicle. Thus, the cost and complexity of
the wireless device may be reduced as only short-range
communications with local APs must be established in order to
maintain and serve continuous communications between the wireless
device and their destination via the wide area network.
[0033] This arrangement allows continuous low power communications
to be maintained with the wireless device as a user leaves building
102, and transits to vehicle 106. Vehicle 106 has an
intra-vehicular WLAN 128 that travels with the vehicle as the
vehicle transits between building 102 and building 104 as shown in
FIG. 1C. Upon arrival at building 104, as depicted in FIG. 1D, WLAN
128 overlaps WLAN 116. This overlap allows the servicing of the
communications for the wireless device to be handed off from the
intra-vehicular network, WLAN 128s, to WLAN 116.
[0034] FIG. 2 depicts various WLANs interconnected by WAN 230 in
which communications to wireless devices are serviced. Each
building 102 and 104, as well as vehicle 106 has placed therein APs
210A, 210B and 210C that service corresponding WLANS 226A, 226B and
226C. Each of these APs 210A-210C may couple to WAN 230 via wired
or wireless network infrastructure.
[0035] Serviced within the buildings 102 and 104 are wireless
telephones/data terminals 220, PDA's 225 and laptop computers 224,
which may be referred to jointly as "wireless devices" or stations
(STAs). Each of these wireless devices communicates with a
servicing AP. For example, laptop computer 224 and wireless
terminal 212 wirelessly communicate with AP 210. Each of the APs
210 supports wireless communications primarily within a designated
area. However, the coverage area of each AP 210 may extend beyond
the boundaries of the serviced building or vehicle so that
overlapping coverage areas exist. For example, in FIG. 1A, APs 108
and 120 simultaneously provide service between building 102 and
vehicle 106. This allows wireless terminals that roam between the
building and vehicle to continue to receive wireless
communications. Some or all of the STAs may also support ad-hoc
networking in which they communicate directly, without AP
interaction.
[0036] Each WLAN has a given coverage area, which may or may not
overlap with the coverage areas of other WLANs. Wireless terminals
220, 222 and 224 and 225 may roam between WLANs 226. A backbone or
transport network 230 communicatively couples the WLANs 226. In
this way, wireless terminals within the covered area of a WLAN
226A, can communicate to other wireless terminals within other
networks. Alternatively, WLANs 226 may communicate with WAN 230 via
an alternative network 232 as shown. This allows WLANs to become
mobile in nature.
[0037] A processor may regulate the data flow and communications
between WLANs 226 to ensure that communications requiring real time
transmissions, such as voice communications or other multi-media
applications take priority and potentially delay communications
having lower priorities. Alternatively, the processor may direct
that should the backbone of the WAN be unable to support the
bandwidth requirements of the real time communications, those
communications may be routed through an alternative network such as
the PSTN, cellular network, a satellite communications network, or
any other like network known to those skilled in the art.
[0038] FIG. 3 provides a partial system diagram wherein WLAN 110
services building 102. WLAN 110 supports at least one standardized
operation having provisions for servicing voice communications,
e.g., IEEE 802.11(a), IEEE 802.11(b), IEEE 802.11(g), etc. The
portion of the WLAN shown includes AP 108 that supports wireless
communications within a serviced area. AP 108 communicatively
couple to WAN 112 to service wireless communications for wireless
devices 122, 124 and 126. Service areas supported by APs 108 and
128 may partially overlap. To service voice calls, WAN 112 may
couple to a Private Branch Exchange (PBX) 304. The PBX couples to
the PSTN, another WAN or an alternative network. These alternative
networks may also tie into WAN 112. These networks may include
cellular infrastructure 136 or satellite infrastructure 137 or
other like networks known by those skilled in the art.
[0039] A PBX may service voice communications for the premises, may
employ packet switched or circuit switched operations, may support
digital or analog operations, include advanced features such as
voice messaging, and support incoming call servicing, outgoing call
servicing, and wireless terminal roaming. A PBX, in conjunction
with WAN 112 and APs 108 and 120, may facilitate roaming operations
between WLAN 110 and 128 and other alternative networks. Roaming
operations may begin prior to a wireless terminal leaving the
coverage area of one WLAN to enter the coverage area of another
WLAN, and during an ongoing call.
[0040] FIGS. 4A-4F provides block diagrams illustrating the typical
components of various wireless terminals used according to this
disclosure. FIG. 4A depicts wireless terminal 400 having only a
short-range digital radio WLAN RF unit 404A that supports
Bluetooth.RTM. or like wireless communications with the WLAN. FIG.
4B includes a cellular RF unit 404B that supports wireless
communications with the cellular network. In this instance, the
parallel path may be established internal to the wireless device.
FIG. 4C includes a WLAN RF unit 404A and satellite RF unit 404C.
FIG. 4D includes cellular RF unit 404B and satellite unit 4004C.
FIG. 4E includes WLAN RF unit 404A, cellular RF unit 404B, and
satellite RF unit 404C. RF units, 404A, 404B and 404C couple to
antennas 402A, 402B and 402C respectively. These antennas 402A,
402B, and 402C may be located internal or external to the case of
the wireless terminal 400. Further, in some embodiments, a single
RF unit and/or a single antenna may support communications with
both the WLAN and the cellular network. Processor 406 may be an
Application Specific Integrated Circuit (ASIC) or another type of
processor capable of operating the wireless terminal 400 according
to this disclosure. Memory 408 includes both static and dynamic
components, e.g., DRAM, SRAM, ROM, EEPROM, etc. In some
embodiments, the memory 408 may be partially or fully contained
upon an ASIC that also includes the processor 406. A user interface
410 includes a display, indicators, a keyboard, a speaker, a
microphone, and/or a data interface, and may include other user
interface components known to those still in the art. RF interfaces
404A, 404B, and 404C, processor 406, memory 408, and user interface
410 couple via one or more communication buses/links 416. Battery
412 or power port 418 couples to and powers RF interfaces,
processor, memory and the user interface.
[0041] FIG. 4F provides a block diagram of a wireless terminal,
which receives wireless communications through antenna 450. A
wireless interface 452 allows the communications received through
antenna 450 to be temporarily stored in a reception buffer 454
prior to being provided to a user, through a user interface, having
a display and/or speaker. Similarly, camera 460 or microphone 462
may be used to take input from the user, which is coded, at CODEC
463 and provided to the transmission buffer 464. A microprocessor
468 may control the functions of the wireless interface with
transmission buffer 464, reception buffer 454, and CODEC 463.
Furthermore, the microprocessor may direct that the CODEC be
adjusted, dependent on the traffic contained within the WLAN or any
path between the transmitting wireless terminal and the
communication's intended destination. By adjusting the CODEC,
quality is adjusted up or down dependent on the available bandwidth
contained within the weakest link in the communication pathway.
[0042] The embodiments of the wireless terminal 400 illustrated in
FIGS. 4A-4F provide examples of wireless terminal configurations.
Many other varied wireless terminal structures may be operated
according to the teachings of the present invention.
[0043] Wireless terminal 400 may execute software instructions,
i.e., Network Interface Instructions (NWII) 414. NWII 414 enables
the wireless terminal 400 to establish parallel communications
between various wireless networks and seamlessly switch the call's
primary servicing network. NWII 414 load from memory 408 into
processor 406 for execution. In other embodiments, these
instructions may be based upon hardware function, firmware
instructions, or a combination of any/all of these. Additionally,
this functionality may be coordinated through an external
processor.
[0044] FIG. 5 provides a flow chart illustrating how an incoming
voice communication may be handled. An incoming voice communication
may be routed to a home WLAN after being received from the PSTN or
other WAN at step 502. A determination is made as to whether the
destination wireless device is currently being serviced by the WLAN
at step 504. If so, WLAN resources are allocated to service of the
incoming call in step 506. The call is then delivered to the
wireless device via the WLAN at step 508.
[0045] When the wireless terminal is not serviced by the home WLAN,
alternative WLANs may be queried to determine if the wireless
device is registered with alternative WLANs. An attempt to route
the call via an alternative network may be made at step 510. The
communication pathway to those alternative WLANs may include
cellular network, e.g., a GSM cellular network, satellite
network(s) or other like network known to those skilled in the art.
If communications are established with the wireless device at step
512, the communication is delivered to the wireless terminal.
[0046] If communications with the wireless terminal cannot be
established (as determined at step 512), the call may be delivered
to another destination such as voice mail or another operator at
step 514.
[0047] FIG. 6 provides a flow chart that depicts the servicing of
an outgoing call. At step 602, the WLAN receives an outbound call
request from the wireless device. A determination is made as to
whether the destination wireless device is currently being serviced
by the same WLAN at step 604. If so, WLAN resources are internally
allocated to service the call at step 606. To allocate resources,
the WLAN may delay some communications having lower priorities. The
call is then delivered to the destination wireless device via the
WLAN at step 608. When the outgoing call is not intended for a
destination serviced by the WLAN, the call is outwardly routed via
the WAN. This communication pathway may include the PSTN, a
cellular network, satellite network, or the Internet, depending on
which WAN the WLAN is coupled to.
[0048] When the destination is not currently being serviced by the
WLAN, attempts are made to reach the destination wireless service
via an alternative network such as cellular. If the wireless
terminal can be reached (as determined at step 612), the call is
delivered to the wireless terminal via the WAN at step 616. If the
wireless terminal cannot be reached via the alternative
network(s)(as determined at step 612), the call is delivered to
another destination at step 614.
[0049] FIG. 7 depicts one method by which communication services
are handed off. Normal call servicing does not require a handoff
(step 700). However, when a handoff may be required, the system
determines the required type of handoff. When a WLAN to WLAN
handoff is required, a parallel communication path is established
and may involve an alternate network at step 704. Then, a
determination is made as to whether the handoff is actually
required by monitoring the communication quality another factor is
between the wireless device and the WLAN at step 706. The
communication quality may be measured by considering the received
signal strength at a servicing AP, the wireless terminal, by
measuring the bit error rate at either the AP or the wireless
terminal, or other method known to those skilled in the art. The
determination may also be based on the location of the wireless
terminal relative to the boundaries of the various WLAN coverage
areas. If handoff is required (as determined at step 706), one of
the parallel paths is dropped and servicing continues via the
remaining pathways. If handoff is not required (as determined at
step 706 by comparing signal quality to predetermined threshold
levels) due to an increase in the communication quality of the
servicing WLAN, the new communication path is dropped at step 710.
From each of steps 708 and 710, operation proceeds to step 700.
[0050] The invention disclosed herein is susceptible to various
modifications and alternative forms. Specific embodiments therefore
have been shown by way of example in the drawings and detailed
description. It should be understood, however, that the drawings
and description thereto are not intended to limit the invention to
the particular form disclosed, but on the contrary, the invention
is to cover all modifications, equivalents and alternatives falling
within the spirit and scope of the present invention as defined by
the claims.
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