U.S. patent number RE42,242 [Application Number 12/179,437] was granted by the patent office on 2011-03-22 for apparatus and method for reallocating communication resources to establish a priority call in a fixed wireless access communication system.
This patent grant is currently assigned to Access Solutions, Ltd.. Invention is credited to Paul F. Struhsaker.
United States Patent |
RE42,242 |
Struhsaker |
March 22, 2011 |
Apparatus and method for reallocating communication resources to
establish a priority call in a fixed wireless access communication
system
Abstract
Apparatus, and an associated method, for a fixed wireless access
communication system, by which to initiate a call to an emergency
dispatch center, or other priority call to a priority location.
When communication resources are initially unavailable to permit
establishment of the call, normal call set-up procedures are
emulated at a subscriber station from which the call is to be
originated. Communication resources are reallocated in the
communication system to permit the establishment of the call is
thereafter established.
Inventors: |
Struhsaker; Paul F. (Plano,
TX) |
Assignee: |
Access Solutions, Ltd. (Dallas,
TX)
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Family
ID: |
34578051 |
Appl.
No.: |
12/179,437 |
Filed: |
July 24, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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60270385 |
Feb 21, 2001 |
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60262712 |
Jan 19, 2001 |
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60262825 |
Jan 19, 2001 |
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60262698 |
Jan 19, 2001 |
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60262827 |
Jan 19, 2001 |
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60262826 |
Jan 19, 2001 |
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60262951 |
Jan 19, 2001 |
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60262824 |
Jan 19, 2001 |
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60263101 |
Jan 19, 2001 |
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60263097 |
Jan 19, 2001 |
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60273579 |
Mar 5, 2001 |
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60262955 |
Jan 19, 2001 |
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60262708 |
Jan 19, 2001 |
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60273689 |
Mar 5, 2001 |
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60273757 |
Mar 5, 2001 |
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60270378 |
Feb 21, 2001 |
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60270430 |
Feb 21, 2001 |
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Reissue of: |
09839727 |
Apr 20, 2001 |
07031738 |
Apr 18, 2006 |
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Current U.S.
Class: |
455/521;
455/404.1; 455/404.2; 455/414.1 |
Current CPC
Class: |
H04L
1/0009 (20130101); H04L 1/007 (20130101); H04W
88/021 (20130101); H04L 1/0005 (20130101); H04M
3/42 (20130101); H04L 12/403 (20130101); H04L
1/0017 (20130101); H01Q 1/246 (20130101); H04L
12/66 (20130101); H04L 12/10 (20130101); H04W
28/18 (20130101); H04W 88/08 (20130101); H04M
2242/06 (20130101); H04M 2207/206 (20130101); H04W
84/14 (20130101); H04L 2001/0098 (20130101); H04M
2242/04 (20130101) |
Current International
Class: |
H04B
7/00 (20060101) |
Field of
Search: |
;455/521,404.1,404.2,414.1,414.2,452.1,422.1,437,509,426.1
;370/338,356 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0 304 955 |
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Mar 1989 |
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EP |
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WO 98/24254 |
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Jun 1998 |
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WO |
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Primary Examiner: Trinh; Tan
Attorney, Agent or Firm: Byrne Poh LLP
Parent Case Text
The present invention claims priority to U.S. Provisional
Application Ser. No. 60/270,385 filed Feb. 21, 2001.
CROSS-REFERENCE TO RELATED APPLICATIONS
The present invention is related to those disclosed in the
following U.S. Provisional and Non-Provisional Patent
Applications:
1) Ser. No. 09/713,684 filed on Nov. 15, 2000, entitled "SUBSCRIBER
INTEGRATED ACCESS DEVICE FOR USE IN WIRELESS AND WIRELESS ACCESS
SYSTEMS";
2) Ser. No. 09/838,810, filed Apr. 20, 2001, entitled "WIRELESS
COMMUNICATION SYSTEM USING BLOCK FILTERING AND FAST
EQUALIZATION-DEMODULATION AND METHOD OF OPERATION";
3) Ser. No. 09/839,726, filed Apr. 20, 2001, entitled "APPARATUS
AND ASSOCIATED METHOD FOR OPERATING UPON DATA SIGNALS RECEIVED AT A
RECEIVING STATION OF A FIXED WIRELESS ACCESS COMMUNICATION
SYSTEM";
4) Ser. No. 09/839,729, filed Apr. 20, 2001, entitled "APPARATUS
AND METHOD FOR OPERATING A SUBSCRIBER INTERFACE IN A FIXED WIRELESS
SYSTEM";
5) Ser. No. 09/839,719, filed Apr. 20, 2001, entitled "APPARATUS
AND METHOD FOR CREATING SIGNAL AND PROFILES AT A RECEIVING
STATION";
6) Ser. No. 09/838,910, filed Apr. 20, 2001, entitled "SYSTEM AND
METHOD FOR INTERFACE BETWEEN A SUBSCRIBER MODEM AND SUBSCRIBER
PREMISES INTERFACES";
7) Ser. No. 09/839,509, filed Apr. 20, 2001, entitled "BACKPLANE
ARCHITECTURE FOR USE IN WIRELESS AND WIRELINE ACCESS SYSTEMS";
8) Ser. No. 09/839,514, filed Apr. 20, 2001, entitled "SYSTEM AND
METHOD FOR ON-LINE INSERTION OF LINE REPLACEABLE UNITS IN WIRELESS
AND WIRELINE ACCESS SYSTEMS";
9) Ser. No. 09/839,512, filed Apr. 20, 2001, entitled "SYSTEM FOR
COORDINATION OF TDD TRANSMISSION BURSTS WITHIN AND BETWEEN CELLS IN
A WIRELESS ACCESS SYSTEM AND METHOD OF OPERATION";
10) Ser. No. 09/839,259, filed Apr. 20, 2001, entitled "REDUNDANT
TELECOMMUNICATION SYSTEM USING MEMORY EQUALIZATION APPARATUS AND
METHOD OF OPERATION";
11) Ser. No. 09/839,457, filed Apr. 20, 2001, entitled "WIRELESS
ACCESS SYSTEM FOR ALLOCATING AND SYNCHRONIZING UPLINK AND DOWNLINK
OF TDD FRAMES AND METHODS OF OPERATION";
12) Ser. No. 09/839,075, filed Apr. 20, 2001, entitled "TDD FDD AIR
INTERFACE";
13) Ser. No. 09/839,499, filed Apr. 20, 2001, entitled "APPARATUS,
AND AN ASSOCIATED METHOD, FOR PROVIDING WLAN SERVICES IN A FIXED
WIRELESS ACCESS COMMUNICATION SYSTEM";
14) Ser. No. 09/839,458, filed Apr. 20, 2001, entitled "WIRELESS
ACCESS SYSTEM USING MULTIPLE MODULATION";
15) Ser. No. 09/839,456, filed Apr. 20, 2001, entitled "WIRELESS
ACCESS SYSTEM AND ASSOCIATED METHOD USING MULTIPLE MODULATION
FORMATS IN TDD FRAMES ACCORDING TO SUBSCRIBER SERVICE TYPE";
16) Ser. No. 09/838,924, filed Apr. 20, 2001, entitled "APPARATUS
FOR ESTABLISHING A PRIORITY CALL IN A FIXED WIRELESS ACCESS
COMMUNICATION SYSTEM";
17) Ser. No. 09/839,734, filed Apr. 20, 2001, entitled "METHOD FOR
ESTABLISHING A PRIORITY CALL IN A FIXED WIRELESS ACCESS
COMMUNICATION SYSTEM";
18) Ser. No. 09/839,513, filed Apr. 20, 2001, entitled "SYSTEM AND
METHOD FOR PROVIDING AN IMPROVED COMMON CONTROL BUS FOR USE IN
ON-LINE INSERTION OF LINE REPLACEABLE UNITS IN WIRELESS AND
WIRELINE ACCESS SYSTEMS";
19) Ser. No. 60/262,712, filed on Jan. 19, 2001, entitled "WIRELESS
COMMUNICATION SYSTEM USING BLOCK FILTERING AND FAST
EQUALIZATIAON-DEMODULATION AND METHOD OF OPERATION";
20) Ser. No. 60/262,825, filed on Jan. 19, 2001, entitled
"APPARATUS AND ASSOCIATED METHOD FOR OPERATING UPON DATA SIGNALS
RECEIVED AT A RECEIVING STATION OF A FIXED WIRELESS ACCESS
COMMUNICATION SYSTEM";
21) Ser. No. 60/262,698, filed on Jan. 19, 2001, entitled
"APPARATUS AND METHOD FOR OPERATING A SUBSCRIBER INTERFACE IN A
FIXED WIRELESS SYSTEM";
22) Ser. No. 60/262,827, filed on Jan. 19, 2001, entitled
"APPARATUS AND METHOD FOR CREATING SIGNAL AND PROFILES AT A
RECEIVING STATION";
23) Ser. No. 60/262,826, filed on Jan. 19, 2001, entitled "SYSTEM
AND METHOD FOR INTERFACE BETWEEN A SUBSCRIBER MODEM AND SUBSCRIBER
PREMISES INTERFACES";
24) Ser. No. 60/262,951, filed on Jan. 19, 2001, entitled
"BACKPLANE ARCHITECTURE FOR USE IN WIRELESS AND WIRELINE
SYSTEMS";
25) Ser. No. 60/262,824, filed on Jan. 19, 2001, entitled "SYSTEM
AND METHOD FOR ON-LINE INSERTION OF LINE REPLACEABLE UNITS IN
WIRELESS AND WIRELINE ACCESS SYSTEMS";
26) Ser. No. 60/263,101, filed on Jan. 19, 2001, entitled "SYSTEM
FOR COORDINATION OF TDD TRANSMISSION BURSTS WITHIN AND BETWEEN
CELLS IN A WIRELESS ACCESS SYSTEM AND METHOD OF OPERATION";
27) Ser. No. 60/263,097, filed on Jan. 19, 2001, entitled
"REDUNDANT TELECOMMUNICATION SYSTEM USING MEMORY EQUALIZATION
APPARATUS AND METHOD OF OPERATION";
28) Ser. No. 60/273,579, filed Mar. 5, 2001, entitled "WIRELESS
ACCESS SYSTEM FOR ALLOCATING AND SYNCHRONIZING UPLINK AND DOWNLINK
OF TDD FRAMES AND METHOD OF OPERATION";
29) Ser. No. 60/262,955, filed Jan. 19, 2001, entitled "TDD FDD AIR
INTERFACE";
30) Ser. No. 60/262,708, filed on Jan. 19, 2001, entitled
"APPARATUS, AND AN ASSOCIATED METHOD, FOR PROVIDING WLAN SERVICE IN
A FIXED WIRELESS ACCESS COMMUNICATION SYSTEM";
31) Ser. No. 60/273,689, filed Mar. 5, 2001, entitled "WIRELESS
ACCESS SYSTEM USING MULTIPLE MODULATION";
32) Ser. No. 60/273,757, filed Mar. 5, 2001, entitled "WIRELESS
ACCESS SYSTEM AND ASSOCIATED METHOD USING MULTIPLE MODULATION
FORMATS IN TDD FRAMES ACCORDING TO SUBSCRIBER SERVICE TYPE";
33) Ser. No. 60/270,378, filed Feb. 21, 2001, entitled "APPARATUS
FOR ESTABLISHING A PRIORITY CALL IN A FIXED WIRELESS ACCESS
COMMUNICATION SYSTEM"; and
24) Ser. No. 60/270,430, filed Feb. 21, 2001, entitled "METHOD FOR
ESTABLISHING A PRIORITY CALL IN A FIXED WIRELESS ACCESS
COMMUNICATION SYSTEM".
The above applications are commonly assigned to the assignee of the
present invention. The disclosures of these related patent
applications are hereby incorporated by reference for all purposes
as if fully set forth herein. The present application hereby claims
the benefit under Title 35, U.S. Code .sctn.119(e) of the above
provisional and non-provisional U.S. Patent Applications.
Claims
What is claimed is:
1. In a multi-user FWA (fixed wireless access) communication system
in which a plurality of subscriber stations are operable to
communicate by way of radio links with network infrastructure to
which a correspondent node is coupled, an improvement of apparatus
for a selected subscriber station of the plurality of subscriber
stations at which a priority call .[.of selected call-type.]. is
selectably originated, said apparatus comprising: a call
establishment message generator coupled to receive an indication of
initiation at the selected subscriber station of origination of the
priority call, said call establishment message generator for
generating a call establishment message for communication to the
network infrastructure to initiate call set-up procedures
precursing a request to establish the priority call between the
selected subscriber station and the correspondent node; a response
detector coupled to receive an indication of a
network-infrastructure generated response to the call establishment
message generated by said call establishment message generator,
said response detector for detecting whether the response to the
call establishment message indicates communication resources to be
available to establish the priority call; and a call set-up
emulator coupled to said response detector, said call set-up
emulator operable to emulate at the selected subscriber station
normal call set-up operations thereat at least for a selected
period responsive to detection by said response detector of
unavailability of the communication resources to establish the
priority call, wherein said correspondent node comprises an
emergency dispatch center having a pseudo-universal dialing code
associated therewith for .Iadd.originating .Iaddend.said priority
call and wherein the selected period is sufficient to determine
whether the pseudo-universal dialing code has been dialed at the
selected subscriber station.
2. The apparatus of claim 1 wherein said call set-up emulator
comprises a dial-tone generator, said dial-tone generator for
generating an audio dial-tone at the selected subscriber station
responsive to detection by said response detector of the
unavailability of the communication resources.
3. The apparatus of claim 2 wherein said .Iadd.selected
.Iaddend.subscriber station comprises a telephonic station having
an actuation keypad actuatable by a user to enter dialing digits
associated with the correspondent node and wherein generation of
the audio dial-tone by said dial-tone generator is terminated upon
commencement of entry of the dialing digits.
4. The apparatus of claim 3 further comprising a dialing-digit
signal generator coupled to receive indications of entry of the
dialing digits at the actuation keypad said dialing-digit signal
generator for generating a dialing-digit indication signal for
communication to the network infrastructure pursuant to the request
to establish the .Iadd.priority .Iaddend.call between the
.Iadd.selected .Iaddend.subscriber station and the correspondent
node.
.[.5. The apparatus of claim 4 wherein the correspondent node
comprises an assistance center having a dialing code formed of
dialing digits associated with the assistance center, wherein the
call of the selected call-type comprises a priority call, and
wherein the dialing-digit signal generated by said dialing-digit
signal generator is of values corresponding to the dialing code
associated with the assistance center when the user actuates the
actuation keypad to cause entry of the dialing digits forming the
dialing code associated with the assistance center..].
.[.6. The apparatus of claim 5 wherein the assistance center
comprises said emergency dispatch center having said
pseudo-universal dialing code associated therewith, wherein the
priority call comprises an emergency call, and wherein the
dialing-digit signal generated by said dialing-digit signal
generator is of values corresponding to the pseudo-universal
dialing code associated with the emergency dispatch center when the
user actuates the actuation keypad to cause entry of the dialing
digits forming the pseudo-universal dialing code..].
7. In the multi-user FWA communication system of claim 1, a further
improvement of apparatus for the network infrastructure, said
apparatus comprising: a call establishment message detector coupled
to receive indications of receipt at the network infrastructure of
the call establishment message; and a response generator coupled to
said call establishment message detector, said response generator
for generating the response of the call establishment message.
8. The apparatus of claim 7 further comprising a communication
resource availability determiner operable responsive to detection
of the call establishment message by said call establishment
message detector, said communication resource availability
determiner for determining whether communication resources are
available to establish the .Iadd.priority .Iaddend.call.
9. The apparatus of claim 8 wherein the network infrastructure is
coupled to the correspondent node by way of a network backbone, and
wherein said communication resource availability determiner
determines both whether communication resources are available upon
the network backbone to establish the .Iadd.priority .Iaddend.call
and whether communication resources are available upon the radio
links to establish the .Iadd.priority .Iaddend.call.
10. The apparatus of claim 8 wherein the .Iadd.selected
.Iaddend.subscriber station further sends a dialing digit
indication signal to the network infrastructure and wherein said
apparatus for the network infrastructure further comprises a
dialing digit indication detector coupled to receive indications of
receipt at the network infrastructure of the dialing digit
indication signal.
11. The apparatus for the network infrastructure of claim 10
further comprising a resource reallocator coupled to said dialing
digit indication detector and to said resource availability
determiner, said resource reallocator selectably operable to
reallocate communication resources in the multi-user FWA
communication system responsive to selected values contained in the
dialing digit indication signal detected by said dialing digit
indication device.
12. The apparatus of claim 11 wherein .[.the correspondent node
comprises said emergency dispatch center having said
pseudo-universal dialing code associated therewith, wherein.]. the
dialing digit indication signal to which said dialing digit
indication detector is coupled to receive indications thereof is of
values corresponding to the pseudo-universal dialing code and
wherein said resource allocator reallocates the communication
resources to provide communication resources to establish .[.a.].
.Iadd.the priority .Iaddend.call between the .Iadd.selected
.Iaddend.subscriber station and the emergency dispatch center.
13. The apparatus of claim 12 wherein the communication resources
of the FWA communication system are utilized pursuant to a
plurality of communication resources with a plurality of subscriber
stations and wherein reallocation made by said resource reallocator
include termination of selected communication resources, thereby to
reallocate resources to establish the .Iadd.priority .Iaddend.call
between the .Iadd.selected .Iaddend.subscriber station and the
emergency dispatch center.
14. The apparatus of claim 13 wherein the communication sessions
have priority levels associated therewith and wherein selection of
termination .Iadd.of .Iaddend.selected communication sessions is
made responsive to the priority levels associated with the
communication sessions.
15. In a multi-user FWA (fixed wireless access) communication
system in which a plurality of subscriber stations are operable to
communicate by way of radio links with network infrastructure to
which a correspondent node is coupled, a method for a selected
subscriber station of the plurality of subscriber stations to
selectably originate a priority call.[.of selected call-type.]. ,
said method comprising: receiving an indication of initiation at
the selected subscriber station of origination of the priority
call; generating a call establishment message for communication to
the network infrastructure to initiate call set-up procedures
precursing a request to establish the priority call between the
selected subscriber station and the correspondent node, wherein
said correspondent node comprises an emergency dispatch center
having a pseudo-universal dialing code associated therewith for
said priority call; receiving an indication of a
network-infrastructure generated response to the call establishment
message; detecting whether the response to the call establishment
message indicates communication resources to be available to
establish the priority call; and responsive to detection of
unavailability of the communication resources to establish the
priority call, emulating normal call set-up operations at the
selected subscriber station at least for a selected period
sufficient to determine whether the pseudo-universal dialing code
has been dialed at the selected subscriber station.
16. The method of claim 15, further comprising: generating an audio
dial-tone at the selected subscriber station responsive to
detection by said response detector of the unavailability of the
communication resources.
17. The method of claim 15, further comprising: generating a
dialing-digit indication signal for communication to the network
infrastructure pursuant to the request to establish the priority
call between the .Iadd.selected .Iaddend.subscriber station and the
correspondent node.
18. The method of claim 15 wherein emulation of normal call set-up
operations at the selected subscriber station at least terminates
in response to determination that the pseudo-universal dialing code
has not been dialed at the selected subscriber station.
19. The method of claim 15, further comprising: terminating use of
selected communication resources of the FWA communication system by
one of a plurality of subscriber stations; and reallocating said
selected communication resources to establish the priority call
from the subscriber .Iadd.selected .Iaddend.station.
20. The method of claim 19, wherein communication sessions for the
FWA communication system have priority levels associated therewith
and wherein selection of said selected communication resources for
termination is made responsive to the priority levels associated
with the communication sessions.
Description
TECHNICAL FIELD OF THE INVENTION
The present invention relates generally to a manner by which to
initiate establishment of a priority call, such as a call to
request emergency assistance in a FWA (fixed wireless access), or
other, communication system. More particularly, the present
invention relates to apparatus, and an associated method, by which
to effectuate the priority call even when communication resources
are not initially available to establish the call. The initial
unavailability of the communication resources is not made known to
the user initiating the call as normal system operation is emulated
at a subscriber station from which the call originates. And, when
the call is determined to be a priority call, the communication
resources of the communication system are reallocated to provide
communication resources to permit the establishment of the priority
call.
BACKGROUND OF THE INVENTION
Telecommunications access systems provide for voice, data, and
multimedia transport and control between the central office (CO) of
the telecommunications service provider and the subscriber
(customer) premises. Prior to the mid-1970s, the subscriber was
provided phone lines (e.g., voice frequency (VF) pairs) directly
from the Class 5 switching equipment located in the central office
of the telephone company. In the late 1970s, digital loop carrier
(DLC) equipment was added to the telecommunications access
architecture. The DLC equipment provided an analog phone interface,
voice CODEC, digital data multiplexing, transmission interface, and
control and alarm remotely from the central office to cabinets
located within business and residential locations for approximately
100 to 2000 phone line interfaces. This distributed access
architecture greatly reduced line lengths to the subscriber and
resulted in significant savings in both wire installation and
maintenance. The reduced line lengths also improved communication
performance on the line provided to the subscriber.
By the late 1980s, the limitations of data modem connections over
voice frequency (VF) pairs were becoming obvious to both
subscribers and telecommunications service providers. ISDN
(Integrated Services Digital Network) was introduced to provide
universal 128 kbps service in the access network. The subscriber
interface is based on 64 kbps digitization of the VF pair for
digital multiplexing into high speed digital transmission streams
(e.g., T1/T3 lines in North America, E1/E3 lines in Europe). ISDN
was a logical extension of the digital network that had evolved
throughout the 1980s. The rollout of ISDN in Europe was highly
successful. However, the rollout in the United States was not
successful, due in part to artificially high tariff costs which
greatly inhibited the acceptance of ISDN.
More recently, the explosion of the Internet and deregulation of
the telecommunications industry have brought about a broadband
revolution characterized by greatly increased demands for both
voice and data services and greatly reduced costs due to
technological innovation and intense competition in the
telecommunications marketplace. To meet these demands, high speed
DSL (digital subscriber line) modems and cable modems have been
developed and introduced. The DLC architecture was extended to
provide remote distributed deployment at the neighborhood cabinet
level using DSL access multiplexer (DSLAM) equipment. The increased
data rates provided to the subscriber resulted in upgrade DLC/DSLAM
transmission interfaces from T1/E1 interfaces (1.5/2.0 Mbps) to
high speed DS3 and OC3 interfaces. In a similar fashion, the entire
telecommunications network backbone has undergone and is undergoing
continuous upgrade to wideband optical transmission and switching
equipment.
Similarly, wireless access systems have been developed and deployed
to provide broadband access to both commercial and residential
subscriber premises. Initially, the market for wireless access
systems was driven by rural radiotelephony deployed solely to meet
the universal service requirements imposed by government (i.e., the
local telephone company is required to serve all subscribers
regardless of the cost to install service). The cost of providing a
wired connection to a small percentage of rural subscribers was
high enough to justify the development and expense of
small-capacity wireless local loop (WLL) systems.
Deregulation of the local telephone market in the United States
(e.g., Telecommunications Act of 1996) and in other countries
shifted the focus of fixed wireless access (FWA) systems deployment
from rural access to competitive local access in more urbanized
areas. In addition, the age and inaccessibility of much of the
older wired telephone infrastructure makes FWA systems a
cost-effective alternative to installing new, wired infrastructure.
Also, it is more economically feasible to install FWA systems in
developing countries where the market penetration is limited (i.e.,
the number and density of users who can afford to pay for services
is limited to small percent of the population) and the rollout of
wired infrastructure cannot be performed profitably. In either
case, broad acceptance of FWA systems requires that the voice and
data quality of FWA systems must meet or exceed the performance of
wired infrastructure.
Wireless access systems must address a number of unique operational
and technical issues including:
1) Relatively high bit error rates (BER) compared to wire line or
optical systems; and
2) Transparent operation with network protocols and protocol time
constraints for the following protocols: a) ATM; b) Class 5 switch
interfaces (domestic GR-303 and international V5.2); c) TCP/IP with
quality-of-service QoS for voice over IP (VoIP) (i.e., RTP) and
other H.323 media services; d) Distribution of synchronization of
network time out to the subscribers;
3) Increased use of voice, video and/or media compression and
concentration of active traffic over the air interface to conserve
bandwidth;
4) Switching and routing within the access system to distribute
signals from the central office to multiple remote cell sites
containing multiple cell sectors and one or more frequencies of
operation per sector; and
5) Remote support and debugging of the subscriber equipment,
including remote software upgrade and provisioning.
Unlike physical optical or wire systems that operate at bit error
rates (BER) of 10.sup.-11, wireless access systems have time
varying channels that typically provide bit error rates of
10.sup.-3 to 10.sup.-6. The wireless physical (PHY) layer interface
and the media access control (MAC) layer interface must provide
modulation, error correction and ARQ protocol that can detect and,
where required, correct or retransmit corrupted data so that the
interfaces at the network and at the subscriber site operate at
wire line bit error rates.
The wide range of equipment and technology capable of providing
either wireline (i.e., cable, DSL, optical) broadband access or
wireless broadband access has allowed service providers to match
the needs of a subscriber with a suitable broadband access
solution. However, in many areas, the cost of cable modem or DSL
service is high. Additionally, data rates may be slow or converge
incomplete due to line lengths. In these areas and in areas where
the high cost of replacing old telephone equipment or the low
density of subscribers makes it economically unfeasible to
introduce either DSL or cable modem broadband access, fixed
wireless broadband systems offer a viable alternative. Fixed
wireless broadband systems use a group of transceiver base stations
to cover a region in the same manner as the base stations of a
cellular phone system. The base stations of a fixed wireless
broadband system transmit forward channel (i.e., downstream)
signals in directed beams to fixed location antennas attached to
the residences or offices of subscribers. The base stations also
receive reverse channel (i.e., upstream) signals transmitted by the
broadband access equipment of the subscriber.
Unfortunately, the diversity of broadband access technology has
resulted in a lack of standardization in the broadband access
equipment. Cable modems and DSL routers are incompatible with each
other and with fiber optic equipment. Different service providers
locate broadband access equipment in different locations on the
subscriber premises. Often this equipment is located inside the
office or residence of the subscriber, which makes it inaccessible
to maintenance workers unless the subscriber is present to admit
the workers to the premises. The lack of standardization of
broadband access equipment and the frequent inaccessibility of such
equipment adds to the cost and complexity of broadband access.
Therefore, there is a need in the art for broadband access
equipment that can be readily and inexpensively deployed in the
large domestic and international markets that are not currently
served by wired or wireless broadband access technology. Further,
there is a need for an apparatus to increase the communication
capacity of the communication system.
Concentration techniques are utilized in construction of many
multi-user communication systems. Concentration techniques,
generally, refer to selection of the number of users permitted to
be part of the system to be greater, by some factor, than the
actual capacity of the communication system. Statistical, or other,
analysis is made of the likely number of users of the communication
system at any particular time, and the system is constructed to
support a number of users based upon the expected number of
users.
During times in which actual usage of the communication exceeds the
capacity of the system, additional users, beyond the system's
capacity, are prevented, or blocked, from access to the system.
When the communication system comprises a conventional wireline,
telephone communication systems, the additional users are provided
indication of their failure to access the system by alerting such
users with audible alerts. The audible alerts are audibly distinct
from normal dial tones generated during normal telephone
operation.
In a fixed wireless access communication system, capacity
limitations are possible between both the network infrastructure of
the system and a correspondent node forming a terminating or
originating station as well as, additionally, the radio links
extending between the network infrastructure and the subscriber
station.
When, for instance, a user at the subscriber station needs to place
a priority call, such as a request for emergency assistance to an
emergency dispatch center, access to the communication system to
communicate with the emergency dispatch center is essential. A need
therefore exists to provide access to a communication system to
establish the priority call with the emergency dispatch center. It
would also be desirable to provide a manner by which to operate the
communication system in which the user is not made aware of an
initial blockage from access to the system if access shall
subsequently be granted.
It is in light of this background information related to radio
communication systems that the significant improvements of the
present invention have evolved.
SUMMARY OF THE INVENTION
The present invention, accordingly, advantageously provides
apparatus, and an associated method, by which to initiate
establishment of a priority call, such as a call to request
emergency assistance, in a FWA (fixed wireless access), or other,
communication system.
Through operation of an embodiment of the present invention, a
manner is provided by which to effectuate the priority cell even
when the communication resources are not initially available to
establish the call.
When a call is initiated, the initial unavailability of the
communication resources is not made known to the user initiating
the call as normal system operation is emulated at the subscriber
station at which the call is originated. The communication
resources of the communication system are reallocated, when the
call is determined to be a priority call, to provide communication
resources to permit the establishment of the priority call.
In one aspect of the present invention, apparatus is provided for a
subscriber station operable in a fixed wireless access
communication system. When a priority call is originated at the
subscriber station, the user of the subscriber station takes the
telephonic station located thereat off-hook. When the telephone
station is off-hook, a call establishment message is generated and
sent by way of a radio link to network infrastructure of the fixed
wireless access system. The establishment message is generated as a
precursor to a request to establish the call between the subscriber
station and another communication station. Detection is made at the
network infrastructure of the call establishment message.
Responsive thereto, determination is made of the communication
resource availability in the communication system to establish an
additional call, of indeterminate priority. A response indicating
whether communication resources are available in the communication
system to establish the call of indeterminate priority is returned
to the subscriber station.
A response detector at the subscriber station is coupled to receive
indications of the response to the call establishment message.
Indication of whether communication resources are available to
establish the call is detected thereat. If communication resources
are unavailable, a call set-up emulator is operable to emulate at
the subscriber station normal call set-up operations. To the user
of the subscriber station at which the call is initiated, call
set-up operations appear to be normally progressing.
Dialing digits associated with the terminating station with which
the call is to be established are entered at the subscriber
station. A dialing digit signal is then sent to the network
infrastructure. Determination is made at the network infrastructure
of the priority to be associated with the call which is to be
established. If the call is a priority call, such as a call to an
emergency dispatch center, e.g., indicated by a pseudo-universal
dialing code, such as 9-1-1, resource reallocations are effectuated
to permit the establishment of the call. Thereafter, the call is
established.
In one implementation, apparatus is provided for a subscriber
station operable in the FWA system. A call set-up emulator is
selectably operable to emulate normal call set-up operations at the
subscriber station even when communication resources are not
initially available to establish a call by the subscriber station.
A dial-tone generator generates a dial tone audibly detected by the
user of the subscriber station in which the call is originated.
Dialing digits associated with the call originated at the
subscriber station are also enterable in apparent normal fashion at
the subscriber station. Upon subsequent reallocation of
communication resources in the FWA communication system, the call
establishment commences in normal manner.
In a further implementation, apparatus is provided for the network
infrastructure of the FWA system, such as at an access processor or
base transceiver station of the system. A detector is coupled to
detect a call establishment message transmitted to the network
infrastructure. Responsive to receipt of the call establishment
message, determinations are made of the availability of
communication resources to establish a call in the communication
system. A response is then sent to the originating subscriber
station. Thereafter, indications of the identity of the terminating
station to which a call is to be established are received at the
network infrastructure. If the identify of the terminating station
indicates that the call is a priority call, reallocation of
communication resources is made, if necessary, to permit the
establishment of the call. If communication resources are not
otherwise available, an ongoing communication session is terminated
to provide the communication resources to effectuate the call.
In these and another aspects, therefore, apparatus, and an
associated method, is provided for a multi-user FWA (fixed wireless
access) communication system in which a plurality of subscriber
stations are operable to communicate by way of radio links with
network infrastructure to which an emergency dispatch center is
coupled. A call request originated by a selected subscriber station
is sent to the network infrastructure to request establishment of a
call between the selected subscriber station and the emergency
dispatch center. A communication resource availability determiner
is operable responsive to receipt at the network infrastructure of
the call request to determine whether communication resources are
available to establish the call between the selected subscriber
station and the emergency dispatch center. A resource reallocator
is coupled to the communication resource availability determiner.
The resource reallocator is selectably operable to reallocate
communication resources in the FWA communication system to permit
establishment of the call between the selected subscriber station
and the emergency dispatch center.
The present invention will be better understood when read in light
of the accompanying drawings which are described in the detailed
description hereinbelow and in light of the claims appended
hereto.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a functional block diagram of an exemplary fixed
wireless access (FWA) network in which an embodiment of the present
invention is operable.
FIG. 2 illustrates a more detailed view of the fixed wireless
access network in FIG. 1, according to an embodiment the present
invention;
FIG. 3 illustrates a functional block diagram of portions of the
fixed wireless access communication system shown in FIG. 1.
FIG. 4 illustrates a message sequence diagram exemplary of
signaling generated during operation of the communication system
shown in FIGS. 1 and 3 pursuant to an embodiment of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring first to FIG. 1, a communication system, shown generally
at 10, provides for communications with the subscriber stations, of
which the subscriber station 12 is exemplary. Communications are
effectuated with the subscriber station by way of radio links
formed upon an air interface 14. Data originated at an
appropriately-positioned subscriber station can be communicated to
a correspondent node, 16 by way of a communication path by way of
the radio links formed upon the air interface. Data originated at
the correspondent node 16 can be communicated upon a communication
path formed between a correspondent node and a subscriber station.
Two-way communication between the subscriber station and the
correspondent node is thereby possible.
In the exemplary implementation, the communication system 10 forms
a fixed wireless access (FWA) system coupled to a network backbone,
of which the combined path data networks (PDN) and public-switched
telephonic network (PSTN) 18 is representative in the figure.
While the following description of operation of an embodiment of
the present invention shall describe its operation with respect to
the exemplary implementation of the communication system shown in
the figure, it should be understood that operation of an embodiment
of the present invention is analogously also operable in other
types of communication systems which use concentration techniques
or otherwise are susceptible to access limitations.
The fixed wireless access system includes a plurality of base
transceiver stations of which the base transceiver/remote modem
(BTS/RM) 22 shown in the figure is exemplary. Each base transceiver
station defines a cell. Here, the base transceiver station 22
defines a cell 24. The subscriber station 12 is here positioned at
a location encompassed by the cell 24. A plurality of other
subscriber stations are also positionable at locations encompassed
by the cell 24. And, other subscriber stations positioned in other
cells defined by other base transceiver stations typically form
parts of a fixed wireless access communication system.
Concentration techniques are used in system construction. That is
to say, system construction permits a high ratio of subscriber
stations to base transceiver stations such that, if all of the
subscriber stations simultaneously attempt to effectuate
communication sessions, the communication capacity of the base
transceiver stations would be exceeded. Through the use of
concentration techniques, a statistical, or other, determination is
made of an appropriate number of subscriber stations to be
permitted to be associated with a particular base transceiver
station. Not all of the subscriber stations are likely to attempt
to effectuate simultaneous communication sessions, thereby
permitting the number of permitted subscriber stations to be
increased.
While any of the a large variety of different types of
communications are effectuable, of significance to an embodiment of
the present invention are telephonic communications originated at
the subscriber station. A telephonic station 26 is here shown to be
located at the subscriber station 12.
Use of the terminology communications by the subscriber station and
by the telephonic station shall be used, at times, interchangeably
below to indicate communications by the telephonic station with the
correspondent node 16. And, while only a telephonic station 26 is
shown to be positioned at the subscriber station, other types of
communication devices such as computer stations and
consumer-electronic devices, can also be represented at the
subscriber station.
An integrated access device (IAD) 28 is also shown to be positioned
at the subscriber station. The integrated access device (IAD) unit
includes transceiver circuitry capable of communicating by way of
the air interface with the base transceiver station 22. The
telephonic station 26 is coupled to the integrated access device 28
and communications are effectuated with the subscriber station by
way of the integrated access device.
The base transceiver station 22 forms a portion of the network
infrastructure of the fixed wireless access system. Groups of base
transceiver stations are coupled to an access processor (AP) 32.
And, in turn, the access process is coupled to the network 18.
During operation of an embodiment of the present invention,
communication resources required to establish a call between the
telephonic station 26 and the correspondence node 16 are selectably
provided. Communication resources both at the air interface 14 and
through the network 18 must be available to establish the call
between the telephonic station 26 and the correspondent node
16.
FIG. 2 illustrates portions of the communication system 10 to
illustrate operation of an embodiment of the present invention.
Operation of an embodiment of the present invention permits a user
of the telephonic station 26 positioned at the subscriber station
12 to originate a call to an emergency dispatch center 34 at which
the correspondent node 16 is located.
Elements shown in the figure are functional representations,
portions of which are implemented, in exemplary implementation, as
algorithms executable at processing devices. Additionally,
functional operation of the various elements, or portion thereof,
can be distributed at several locations or elements of the
communication system. Here, for instance, the transmit and receive
circuitry portions 36 and 38 are implemented at the integrated
access device 28, at the telephonic station 26, or at other
portions of the subscriber stations.
When a call is placed to the emergency dispatch center, a
pseudo-universal dialing code, such as a 9-1-1 dialing code is
entered at the telephonic station of the subscriber station.
A user interface 42 is also positioned at the subscriber station.
The user interface includes, for instance, an actuation key pad
located on the telephonic station which permits user actuation
thereof to enter dialing digits associated with a terminating
station such as the correspondent node 16 at the emergency dispatch
center 34. The user interface is also representative of a hook
switch associated with the telephonic station upon which a
telephonic handset is conventionally positioned, to be removed
therefrom when a call is to be initiated.
The user interface is coupled to apparatus 44 of an embodiment of
the present invention. The apparatus 44 is formed of functional
elements implemented, for instance, by algorithms executable by
control circuitry.
Here, a call establishment message generator 46 is coupled to the
user interface to receive indications of off-hook indications
indicated thereat. An off-hook indication is indicated when a
telephonic station is taken off the hook switch when a user intends
to initiate a call with a terminating station. The call
establishment message generator generates a call establishment
message when the off-hook indication is provided thereto. The call
establishment message is provided to the transmit circuitry 36 to
be transmitted to the network infrastructure to inform the network
infrastructure of the imminent request for establishment of a call
with a terminating station.
The network infrastructure, here formed of both the base
transceiver station 22 and access processor 32 is also shown to
include both transmit circuitry and receive circuitry portions 52
and 54, respectively. The transmit and receive circuitry portions
are implemented, for example, at the base transceiver station
22.
The call establishment message transmitted by the subscriber
station to the network infrastructure is detected at the receive
circuitry 52. Apparatus of an embodiment of the present invention,
here referenced at 56 is coupled to the receive and transmit
circuitry 52 and 54. Elements forming the apparatus 56 are also
functionally represented and can be implemented in any of various
manners, including by algorithms executable by control circuitry.
And, the elements forming the apparatus 56 can be distributed at
different locations of the network infrastructure or coupled
thereto.
When a call establishment message is received at the receive
circuitry, detection is made of its reception by a call
establishment message detector 58. The call establishment message
detector is coupled to a communication resource availability
determiner 62. The communication resource availability determiner
is operable at least responsive to detection of reception of the
call establishment message at the network infrastructure. The
communication resource availability determiner is operable to
determine the availability of communication resources, both in the
network 18 and upon the air interface 14, of communication
resources to establish a call of indeterminate priority.
Determinations are made, for instance, responsive to indications of
other ongoing communication sessions with other subscriber stations
as well as ongoing communication sessions making use of the network
18.
Determinations made by the determiner 62 are provided to a response
generator 64. The response generator generates a response signal
which is provide to the transmit circuitry 54. The response signal
is transmitted by way of the air interface 14 to the subscriber
station 12. The response serves to acknowledge reception at the
network infrastructure of the call establishment message and also
to provide an indication to the subscriber station of the
availability of communication resources to establish a call
originated at the subscriber station.
When the response is received at the receiver circuitry 38 of the
subscriber station, a response detector 68 detects reception at the
subscriber station of the response. If the response indicates that
communication resources are unavailable to establish a call,
originated at the subscriber station, an indication is provided to
a call set-up emulator 72. The call set-up emulator is operable to
emulate normal operation of call set-up procedures even though the
response indicates the communication resources to be unavailable to
establish the call. The call set-up emulator includes, for
instance, a dial tone generator which generates a conventional
telephone dial tone audibly detectable by a user of the telephonic
station. Here, the oscillator 74 is representative of an
oscillation signal used in the generation of a dial tone. The
emulator is also coupled to the user interface 42 to receive
indications of dialing digits or other actuator inputs input by way
of the user interface. For instance when dialing digits are
entered, the generated dial tone is terminated and appropriate
audibly-detectable tones are generated responsive to the entry of
the dialing digits or other input actuations.
Indications of the entered dialing digits are also provided to a
dialing digit signal generator 76. The dialing signal generator
generates a dialing digit signal which is provided to the transmit
circuitry 36 to be transmitted to the network infrastructure.
When the dialing digit signal is received at the receive circuitry,
detection of the signal is made by a dialing digit indication
detector 82. The detector 82 detects the values of the dialing
digits. Detection is at least made as to whether the values of the
dialing digits are those corresponding to the emergency dispatch
center, or other priority location. When detection is made of
dialing digits corresponding to the emergency dispatch center, or
other priority location, an indication of such is given to a
resource reallocator 84. The resource reallocator is operable to
reallocate the allocation of communication resources in the
communication system to permit the establishment of the call
between the subscriber station and the emergency dispatch center.
Resource reallocation caused to be effectuated by the resource
reallocator includes, for instance, termination of ongoing
communication sessions to make available the communication
resources to permit the call to the emergency dispatch carrier, or
other priority location, to be established. Selection of which of
the ongoing communication session, or sessions, to be terminated is
made, for instance, upon random selection, or based upon
subscription service levels to which the different subscriber
stations have subscribed.
Thereby, a call is able to be established between the subscriber
station and the emergency dispatch center, even when the
communication resources are not initially available to permit the
establishment of the call. And, through the use of the call set-up
emulator at the subscriber station, the originator of the call is
not made aware of the initial unavailability of the communication
resources.
FIG. 3 again shows portions of the fixed wireless network, here
shown at 300 of an embodiment of the present invention. The Fixed
wireless network, is here show to include a subscriber integrated
access device (SIAD) 304 located at a subscriber premises. The SIAD
304 includes radio circuitry 306 capable of transceiving radio
signals. With a transceiver base station 308.
The radio circuitry 306 of the SIAD 304 is here capable of
generating both voice and data packets, here represented by the
blocks 312 and 314. The voice packages are representative of voice
packets generated during operation of a telephony handset which is
operable in convention manner but connected to the radio circuitry
of the SIAD.
The transceiver base station is coupled to an access processor
shelf 322 which here functionally is shown to include a table 324
at which active call information is stored, and a resource
allocator 325 which allocates communication resources in the fixed
wireless network.
The access processor communicates traffic and signaling information
by way of the element 328 on the lines 332 with a network interface
334.
The network interface 334 is coupled to the PSTN/IP network
336.
The network 336, is in turn, connected to a communication station,
here located at an emergency dispatch center 338.
A telephony handset located at the SIAD 304 can be used, for
instance, to phone an emergency request for emergency assistance to
personnel at the emergency dispatch center. The call, when
established, permits a call originator who places the call to
request emergency assistance.
Due to the potentially emergency nature of the call, it is
essential that the call be established. Due to the use of
concentrated techniques in system construction, there is a
possibility that system capacity would not permit establishment of
the call, and the request for emergency assistance at the emergency
dispatch center would not be completed.
During operation of an embodiment of the present invention, a
manner is provided by which to better assure that the call is
established.
FIG. 4 illustrates a message sequence diagram, shown generally at
400, representative of operation of a fixed wireless network shown
in FIG. 3. Signaling is initiated at the SIAD 304 when a telephony
handset is taken off-hook. As soon as the telephony handset is
taken off-hook, a call establishment message is generated,
indicated by the segment 404, and sent to the access processor 322.
A determination is made as to whether resources are available to
establish a call. In the exemplary scenario, resources are not
available to establish a call, and an indication of the
unavailability of the resources, indicated by the segment 406, is
returned to the SIAD.
Upon receipt of the indication of the unavailability of the
resources, normal call set-up procedures are emulated, indicated by
the block 408, emulsion procedures include, for instances,
generation of a dial tone which is local to the SIAD but otherwise
appearing to be normal operation of the telephony handset to a user
thereof. The user, upon detecting the dial tone, dials, or
otherwise enters, digits associated with the emergency dispatch
center, such as the emergency digits 9-1-1 forming a pseudo
universal emergency number in the United States. The entered digits
of the dialing code are captured, indicated at the block 410, and a
digit message is generated and transmitted by the segment 412 to
the access processor 322.
At the access processor a determination is made as to whether the
values of the digits contain in the digital message are associated
with the emergency dispatch center or are otherwise associated with
the priority call. If not, a terminate call message indicated by
the segment 414 is returned to the SIAD. A terminate call message
is identified at the telephony handset at the SIAD as a fast busy
signal.
If, conversely, the digit message is of values corresponding to an
emergency dispatch center, or is otherwise representative of a
priority call, a decision is made to permit the establishment of
the call. To free resources to permit the establishment of the
call, a nonpriority call is terminated, indicated by the block 416.
A non priority call is terminated, such as by randomly terminating
an active call selected from the table 324, (shown in FIG. 3). A
priority might also be associated with the act of calls, and a
lowest-priority act of call is first-terminated. Or a random
termination of a lowest-priority call is performed. Thereby,
resources are made available to establish the call between the
telephony handset and the emergency dispatch center. Thereafter,
and as indicated by the segment 418, a message is sent to the PSTN
to cause a call to be established therethrough. Normal call
operations, indicated by the block 422 is thereafter effectuated at
the 911, or other priority call, continues until one side, or the
other, of the communication sessions goes on-hook.
The previous descriptions are of preferred examples for
implementing the invention, and the scope of the invention should
not necessarily be limited by this description. The scope of the
present invention is defined by the following claims.
* * * * *