U.S. patent application number 09/223322 was filed with the patent office on 2002-05-16 for method and apparatus for providing neighborhood cordless services.
Invention is credited to CHOW, ALBERT, MILLER II, ROBERT RAYMOND, RUSSELL, JESSE EUGENE, WANG, SPENCER, YING, WENCHU.
Application Number | 20020058495 09/223322 |
Document ID | / |
Family ID | 22836015 |
Filed Date | 2002-05-16 |
United States Patent
Application |
20020058495 |
Kind Code |
A1 |
CHOW, ALBERT ; et
al. |
May 16, 2002 |
METHOD AND APPARATUS FOR PROVIDING NEIGHBORHOOD CORDLESS
SERVICES
Abstract
A method for providing a local cordless service comprises the
steps of receiving subscriber neighborhood zone selection input so
that a mobile telephone equipped subscriber may place or receive
calls for a fixed rate, for example, per month without having to
pay radio frequency air time charges any time they are located
within their selected subscribed-to zones. If the subscribed-to
zones are adjacent to one another and the mobile subscriber roams
from one zone to another, the subscriber may continue their free
call uninterrupted and without paying air time charges. However,
when the subscriber roams outside their subscribed-to zones they
may be switched from the present local cordless services to
conventional personal communications services and pay air time
charges. However for an active call, no air-time charges are
incurred as the user transitions between the cellular/DPCS
environment and the local cordless service environment. Associated
apparatus comprises an IBS for automatically changing radio
frequency channels as the subscriber roams within a subscribed-to
neighborhood zone, roams to another subscribed-to zone or roams
outside a subscribed-to zone. Subscribers may choose to use their
mobile identification number, their current directory telephone
number for wired public switched telephone service or obtain a new
directory number.
Inventors: |
CHOW, ALBERT; (HILLSDALE,
NJ) ; MILLER II, ROBERT RAYMOND; (MORRIS, NJ)
; RUSSELL, JESSE EUGENE; (PISCATAWAY, NJ) ; WANG,
SPENCER; (PARSIPPANY, NJ) ; YING, WENCHU;
(CEDAR KNOLLS, NJ) |
Correspondence
Address: |
S H DWORETSKY
AT&T CORP
PO BOX 4110
MIDDLETOWN
NJ
07748
|
Family ID: |
22836015 |
Appl. No.: |
09/223322 |
Filed: |
December 30, 1998 |
Current U.S.
Class: |
455/406 ;
455/407 |
Current CPC
Class: |
H04M 2215/7435 20130101;
H04W 48/18 20130101; H04M 15/8038 20130101; H04M 15/8083 20130101;
H04M 15/8033 20130101; H04M 2215/0184 20130101; H04M 2215/34
20130101; H04M 2215/2026 20130101; H04M 2215/7442 20130101; H04W
4/24 20130101; H04M 2215/32 20130101 |
Class at
Publication: |
455/406 ;
455/407 |
International
Class: |
H04M 011/00 |
Claims
What we claim is:
1. A method of providing a local cordless service to a subscriber
having a mobile station for communicating with a radio base station
serving a plurality of said subscribers to said service comprising
the steps of: forming a plurality of local cordless services zones
having a radius from a plurality of respective said radio base
stations; receiving subscriber selection criteria of at least one
selected zone, said radio base station for radiating and receiving
radio frequencies for communication with mobile wireless subscriber
apparatus; and billing a fixed rate per service period for using
said mobile subscriber apparatus when said mobile subscriber
apparatus is located within said one selected zone regardless of
the number of calls placed from said apparatus or the use of radio
frequency spectrum by said apparatus.
2. A method of providing local cordless services as recited in
claim 1 further comprising the step of: receiving subscriber
selection criteria of a selected second zone, said selected zone
overlapping said at least one selected zone; and billing an
additional fixed rate per service period for using said mobile
subscriber apparatus when said mobile subscriber apparatus is
located within one of said one selected zone and said selected
second zone.
3. A method of providing local cordless services as recited in
claim 1 further comprising the step of: receiving subscriber
selection criteria of a selected second zone, said selected zone
being located remote from said at least one selected zone; and
billing an additional fixed rate per service period for using said
mobile subscriber apparatus when said mobile subscriber apparatus
is located within one of said one selected zone and said selected
second zone.
4. A method of providing local cordless services as recited in
claim 2 further comprising the step of: monitoring said mobile
subscriber apparatus during a call; and permitting a call to
continue without additional charge as said mobile subscriber
apparatus roams via a buffer overlap area from said one selected
zone to said selected second zone.
5. A method of providing local cordless services as recited in
claim 3 further comprising the step of: monitoring said mobile
subscriber apparatus during a call; permitting a call to continue;
and billing additional charges for air time as said mobile
subscriber apparatus roams from said one selected zone to said
selected second zone what's this.
6. A method as recited in claim 5 wherein said call continue
permission step comprises the steps of: alerting a subscriber that
said call will be continued as a wireless charged for call;
obtaining a new radio frequency channel within an overlapping
wireless cell; and tuning to the new radio frequency channel.
7. A method as recited in claim 1 further comprising the steps of:
receiving subscriber selection of one of a mobile identification
number based service and a directory number based service and
assigning a directory number according to said choice.
8. A method as recited in claim 7 wherein said directory number is
ported from a wired public switched telephone service for the same
subscriber.
9. A method of providing a local cordless service as recited in
claim 1 wherein said one selected zone has a radius of greater than
one mile from said mobile station of said subscriber.
10. A local cordless service system comprising a mobile station
having a transmission range of: at least one mile, a wired base
station for receiving communications from a plurality of said
mobile stations, two of said mobile stations being of different
subscribers, and billing apparatus for billing each said different
subscriber a flat rate for communications within a selected zone
surrounding said wired base station.
11. A local cordless service system as recited in claim 10 wherein
said mobile station is addressed in accordance with a directory
number carried from disconnected wired telecommunications
service.
12. A local cordless service system as recited in claim 10 further
comprising a network server platform for storing a subscriber
profile, the subscriber profile including billing data and
subscriber-to service data for each of said two different
subscribers.
13. A local cordless service system as recited in claim 10 further
comprising two of said radio base stations and a remote digital
terminal for concentrating ISDN BRI lines from said radio base
stations to GR 303 trunks to a serving switch.
14. A local cordless service system as recited in claim 13 wherein
one of said radio base stations services said selected zone and the
other of said radio base stations services another selected zone,
such that when said mobile station moves from one zone to another
zone during a call in progress, said one base station hands off the
call to the other of said radio base stations without additional
charge.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] This invention relates to the field of providing
neighborhood cordless services at a single rate such that there is
no air time charge for calls made within a home neighborhood zone
or subscribed-to visiting neighborhood zone(s).
[0003] 2. Description of the Related Arts
[0004] It is known to provide wireless services for a fixed fee and
to charge additional air time fees for each period of time that a
subscriber to the wireless services is using the radio frequency
spectrum. Such services were initiated in the 1970's as analog
wireless services and have become digital over time, for example,
the relatively new digital personal communications services
(DPCS).
[0005] It has been known up until recently to permit users to have
cordless telephone apparatus comprising a base station and a mobile
unit such that the mobile unit may communicate with the base
station over limited distances of several hundred feet. Recently,
in the United States, however, a band of frequencies has been made
available in the 900 MHZ range for providing cordless telephone
service where the mobile station can be as far removed from the
base station portion of the station apparatus by as much as one
mile under optimal conditions. Consequently, a user would not have
to pay for air time charges as in wireless services such as
personal communications services if a mobile station is confined
within one mile radius of the typically home-located base
station.
[0006] Fixed wireless subscriber loop services are also known.
Equipment for providing such services is available from suppliers
such as Diva Communications and OptoPhone Systems. The fixed
wireless subscriber loop concept has been used successfully to
provide telephone services to remote, for example, mountainous
regions. To provide a copper wire subscriber loop to such customers
can cost hundreds of thousands of dollars per subscriber.
Subscribers to a fixed wireless subscriber loop system have an
antenna mounted to their home or business and receive an equivalent
of wired services over a wireless link to an antenna site, for
example, on the top of the mountain. Service can be provided for a
fixed rate, the copper subscriber wired loop eliminated and no air
time charges are charged.
[0007] There is still a need in the art for a wireless service that
would permit a mobile subscriber to roam within a zone close to
their home in the same way as a 900 MHZ cordless customer is free
to carry their cordless phone from room to room. A mobile
subscriber should be able to roam and also move from one zone to
another or make calls from non-contiguous zones without having to
pay for air time charges. In today's cellular environment, airtime
is charged. The current fee structure thus has very little
incentive for customers to continue use their cellular phones when
they have access to a home-based landline phone. In order to
achieve the objectives of one phone, one number anytime and
anywhere communications, it is imperative that a neighborhood or
local `cordless type` of services be provided to all the public
cellular/PCS subscribers and with incentive to use the same PCS
phone in the home/office and around the neighborhood area without
air time charges. A subscriber should not lose a call in progress
as they move from one subscribed-to zone to another adjacent
subscribed zone, and should have the opportunity to switch
automatically to known DPCS services and pay air time charges
should they so choose.
SUMMARY OF THE PRESENT INVENTION
[0008] Subscribers to a local cordless service according to the
present invention may subscribe to a home neighborhood zone and
optionally one or more visiting neighborhood zones from which the
subscribers may place telephone calls without having to pay air
time charges. By local cordless service is intended a mobile
wireless subscriber loop service wherein stations are mobile and
the susbcriber loop to the customer's premises may be replaced with
a wireless loop. The subscriber need not maintain their wired
connection to a local exchange carrier (LEC). If the subscribers
are current public digital PCS service users, they may use their
existing cellular phone and unique mobile identification number
(MIN) for subscription to the service. Subscribers may also have
the option of electing new wireline numbers to be assigned to their
cellular phone for subscription of the service and the numbers
assigned may be the traditional PSTN directory number (DN).
Alternatively, the subscribers can elect to port their existing
wireline DNs to this service. If the subscriber is not a public
cellular user, they will need a cellular phone or other mobile
station (MS) assigned with either a new DN or their ported DN from
the incumbent local exchange carrier (ILEC).
[0009] According to one embodiment of the present invention, a
subscriber to such a mobile service pays a flat rate that is
competitive with or even less expensive than a subscriber to
conventional wired public switched telecommunications services. In
their home zone, which may be approximately the same size as, or
even slightly larger in size than, the range of a standard 900 MHZ
cordless phone, the subscriber may carry or otherwise receive
services at one flat rate (regardless of air time used). For
additional flat fees, the subscriber may also make calls in one or
more visited zones which may be contiguous with or remote from the
home zone.
[0010] When a subscriber travels between the subscribed home zone
and an adjacent visiting zone or between adjacent visiting zones,
the call may be handed off to the other zone without interruption
to the call in progress. Also, when a subscriber moves from any
subscribed zone to a public cellular/PCS environment, the call may
be handed off without air time charges for the duration of the same
call.
[0011] As a subscriber leaves their home zone and roams toward a
remote (i.e., non-adjacent) visited zone, there exist at least
three alternative ways of billing a call in progress. In one
embodiment, the call in progress will be terminated when the
boundaries of the subscribed-to zone are reached. In another
embodiment, the call will be allowed to continue without air time
charges for a predetermined period of time as a public cellular
carrier (e.g., a conventional digital personal communications
service call). In this invention the preferred method is to allow
the call to continue but the subscriber will be switched over to
public cellular carrier frequency without air-time charges for the
duration of the same call
[0012] These and other features of the present invention will be
understood from studying the drawings and the following detailed
description of various embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a functional block schematic drawing of an
exemplary network architecture for providing LCS Local Cordless
Services (LCS) and for describing call processing.
[0014] FIG. 2 is a functional block schematic drawing of the
intelligent base station (130) shown in FIG. 1.
[0015] FIG. 3 shows the message flow process between a mobile
station (MS) and a network server platform (NSP) and associated
database (ID) for downloading a number assignment module (NAM).
[0016] FIG. 4a shows an exemplary call processing flow for
registration of a mobile station with a mobile identification
number (MIN) in its associated home neighborhood zone (HNZ).
[0017] FIG. 4b shows an exemplary call processing flow for
registration of a mobile station with a directory number (DN) in
its associated home neighborhood zone (HNZ).
[0018] FIG. 4c shows an exemplary call processing flow for
registration of a DN-based mobile station in a subscribed-to
visiting neighborhood zone (VNZ).
[0019] FIG. 5a shows an exemplary call processing flow for a call
delivered to a mobile station with a mobile identification number
(MIN).
[0020] FIG. 5b shows an exemplary call delivery to a DN-based
subscriber in the HNZ via the home IBS.
[0021] FIG. 5c shows an exemplary call delivery to a visiting
neighborhood zone for a DN-based subscriber registered with the
visited V-NSP.
[0022] FIG. 5d shows an exemplary call processing for a ported DN
based subscriber in their HNZ.
[0023] FIG. 5e shows an exemplary call processing for a ported DN
based subscriber in a visited zone.
[0024] FIG. 5f shows an exemplary call delivery for a DN-based
subscriber using the Advance Intelligent Network triggers.
[0025] FIG. 6a shows an exemplary intra-cell call hand-off FIG. 6b
shows an exemplary inter-cell call hand-off within, for example,
NSP 145-1.
[0026] FIG. 7 shows an exemplary outgoing call from a LCS
subscriber from a registered zone.
DETAILED DESCRIPTION
[0027] Referring to FIG. 1, there is shown an exemplary system
architecture for providing local cordless services (LCS) according
to the present invention. LCS according to the present invention
essentially provides a mobile wireless subscriber loop. If a
subscriber so chooses, the subscriber may disconnect their wired
telephone service provided by their incumbent local exchange
carrier (ILEC) and utilize their same directory number (DN) via the
present local cordless service. The system architecture of FIG. 1
may be overlaid on an existing public switched telephone service
network (PSTN) 100 shown above and to the right of a public
cellular network cell 101-2 of known cellular wireless service
(WS). The LCS service may likewise be overlaid and be provided from
the same antenna sites as a conventional cellular wireless service
or personal communications service. It is envisioned that the LCS
radio equipment 130-1, 130-2 can also be attached to telephone
poles. For ease of understanding, FIG. 1 presents the PSTN 100 as a
separate network entity away from the LCS. Thus, FIG. 1 is
simplified to the extent that the conventional wired PSTN 100 may
actually surround and include a local cordless services network
according to the present invention in much the same way that today
a PSTN network 100 surrounds and includes a typical cellular mobile
wireless service (WS) network comprising cells 101-1 to 101-7 or
digital personal communication service (DPCS) network. As will be
further described herein, the LCS service network defines a
plurality of neighborhood zones, which may comprise home
neighborhood zones (HNZs) 105-1 and visiting neighborhood zones
(VNZs) 115-1, 115-2 from the point of view of an individual
subscriber to the LCS service of the present invention.
[0028] In fact, the present LCS service may utilize WS, PCS, and/or
DPCS infrastructure such as antenna sites and subscriber apparatus.
One advantage of the LCS service is its efficient use of the
surrounding network's bandwidth capacity. As will be further
described herein, unused channels in the 800 MHZ and 1800 MHZ
spectra for WS, PCS, and/or DPCS service may be dynamically
allocated to LCS service as taught by U.S. Pat. Nos. 5,809,423
(issued Sep. 15, 1998), 5,787,352 (issued Jul. 28, 1998), 5,740,536
(issued Apr. 14, 1998), 5,513,379 (issued Apr. 30, 1996), 5,404,574
(issued Apr. 4, 1995), and 5,345,499 (issued Sep. 6, 1994), all
issued to B. Mathilde et al., which are all incorporated by
reference herein in their entireties. Moreover, as taught by these
patents, the radio frequency cells may be dynamically configured
according to algorithms described therein.
[0029] LCS service also differs from current cellular/DPCS service
in that the LCS radio equipment interfaces to a local digital line
switch and not to a mobile switching center. The local switch
provides bearer channels and feature applications as well as the
switching fabric for wired lines. The mobile switching center
provides comparable capabilities to the cellular/DPCS network.
Utilizing a local digital line switch enables LCS to provide
feature applications to the LCS subscriber currently available to
wired telephony but unavailable via the MSC 180 in wireless
telephony. Another feature of LCS is that the LCS radio equipment,
the IBS, 130-1, 130-2, 130-3 interfaces to the local switch via
ISDN BRI lines and the IBS uses Q.931 signaling for call processing
with the LDS 140-1, 140-2. IBS 130-1 and 130-2 interface via ISDN
BRI lines to remote digital terminal RDT 178 which is a remote
digital terminal for concentrating lines known in the art to a GR
303 line to LDS 140-2. IBS 130-3 communicates with LDS 140-1 via
ISDN BRI 135-3. This interface is a widely supported open standard
interface and thus the LCS radio equipment, for example, IBS 130-1,
130-2, 130-3, can interwork with any local switch that supports the
integrated services digital network (ISDN). Therefore LCS radio
equipment appears to the switch as an ISDN terminal station and the
radio equipment is responsible for terminating Q.931 protocol and
establishing the RF link.
[0030] A subscriber 10 in a home neighborhood zone (HNZ) 105-1 of
wireless service (WS) cell 101-2 may be a PSTN 100 service
subscriber and have a hard-wired telephone (not shown) at their
residence within the HNZ 105-1. A local cordless services according
to the present invention is not limited by the extensive investment
in copper cable distribution facilities which will be referred to
herein as a wired subscriber loop. That copper investment (made in
a PSTN 100 environment) is avoided with local cordless services
according to the present invention. Thus, LCS service is expected
to be less expensive to subscribers than conventional wired PSTN
service.
[0031] Subscriber 10 to a copper-wired PSTN 100 may pay, for
example, a fixed rate for telephone service each month and receive
unlimited incoming calls within a local calling zone, for example,
HNZ 105-1. The typical subscriber 10 may also place free outgoing
calls from their residence within the same local calling zone.
[0032] According to the present invention of providing local
cordless services in the same area, subscriber 10 may not have
wired, fixed location apparatus but may be equipped with a mobile
cellular telephone or digital personal communications service
telephone, for example, a TIA/EIA/Interim Standard-136 compliant
DPCS mobile station (MS) 10. For the same monthly rate or a lower
monthly rate than the same subscriber may pay for fixed, wired PSTN
100 service, the subscriber with MS 10 may receive local cordless
services. Thus, the LCS subscriber will have equivalent, or in many
respects superior, features (such as one number type of mobility
service) to a wired PSTN subscriber for the same or lower cost.
[0033] Now the present invention of providing a local cordless
services also differs from a typical cellular telephone service or
personal communications service (PCS), in that both of these
conventional services charge air time beyond a flat rate for
service. In other words, these conventional services apply an
additional per-minute charge for use of the radio frequency
spectrum. The present invention of providing a local cordless
services permits unlimited air time within the home neighborhood
zone 105-1 and any subscribed visiting neighborhood zone(s), for
example VNZ 115-1, 115-2, such that the amount billed per service
period is fixed, regardless of the amount of airtime used.
[0034] Also, the present invention is comparable with the provision
of conventional so-called 900 MHZ cordless handsets which
communicate with a wired home base station. While it is urged by
proponents of such apparatus that such phones are portable and may
be used as far away as one mile (or more) from associated home base
stations, in practice, many such phones are not capable of
operating further than hundreds of feet from their wired base
stations, for example, because of unfortunate antenna location, the
personal use of the mobile handset portion or the placement of the
base station or handset portion within a radio frequency shielded
residence or automobile or because of other environmental factors.
Another limitation for using a 900 MHz phone is that free airtime
can only be achieved when using it around the wired home base
station. There is no such concept of visiting zone(s) 115-1,
115-2.
[0035] The Home Neighborhood Zone (HNZ)
[0036] According to the present invention, each subscriber with LCS
mobile station (MS) 10 (this subscriber may or may not have a
landline phone but must have a cellular phone or other mobile
station (MS) in order to use the invention) will be given the
opportunity to make calls free of air time charges anywhere within
their home neighborhood zone 105-1. Subscriber MS 10 may roam
throughout the home neighborhood zone and make calls for free
within that zone. Another subscriber, for example, subscriber MS
150 may have a different home neighborhood zone that is defined by
their residence location within that zone. The subscriber may be
coincidentally located near the center of their HNZ 105-1 or toward
its perimeter. The HNZ thus is a fixed geographic pattern that may
have any desired shape surrounding an intelligent base station
(IBS) and antenna site, in this example, IBS 130-2. The HNZ 105-1
may have an elongated shape or other shape to obtain, for example,
a large calling and callable population of subscribers. In the
drawing, the pattern is shown as a circle by way of example only
and the choice of a circle for depiction in the drawing should not
be construed to be limiting. In one embodiment, the pattern may
have a radius of between one and one half mile and two miles. In
another embodiment, the pattern may have a radius of one half of a
mile to one and one half mile, or two to 4 miles. In another
embodiment, the HNZ 105-1 may have a diameter of as much as seven
to ten miles. In another embodiment, the shape of the pattern in
relation to neighboring zones may be that of an ellipse. The design
of HNZ's and visiting neighborhood zones (VNZ's) may be a process
involving the calculation of frequent calling patterns and the
desirability of inclusion within the zone of frequently called
commercial and retail establishments. The design may become an art
as well as a science. The concept, however, is clearly to provide
at least equivalent service to 900 MHZ cordless telephone service
and to provide better than equivalence with respect to the mobility
of the phone with wired PSTN 100 service.
[0037] The Visiting Neighborhood Zone (VNZ)
[0038] The LCS service may comprise a first flat monthly rate for a
home neighborhood zone 105-1 and permit additional air time free
calling zones named herein as visiting neighborhood zones (VNZ)
115-1, 115-2 for an additional nominal flat rate per each
additional visiting neighborhood zone. For subscriber MS 10 whose
HNZ is zone 105-1, subscriber MS 10 may have one or more visiting
neighborhood zones (VNZ) 115-1, 115-2. The VNZ need not be
contiguous with the HNZ, for example, as VNZ 115-1 is contiguous
with HNZ 105-1 and VNZ 115-2 is not contiguous with HNZ 105-1. The
VNZ's may overlap other VNZ's or HNZ's more than is shown in FIG.
1. When loosely overlapping, for example, the buffer zone 195-1
within the HNZ or buffer zone 195-2 within VNZ 115-1 may provide
subscriber with the ability to travel without loosing a connection
between VNZ and VNZ or between HNZ and VNZ. The rate the subscriber
must pay may vary with the subscribed to visiting zone VNZ or
simply be constant for each VNZ added. In another rate plan, the
first VNZ may be offered at a given rate and the next VNZ may be
added at a lesser additional flat rate. What may be a visiting
neighborhood zone 115-1, 115-2 for one subscriber such as
subscriber 10 will be a home neighborhood zone for another
subscriber whose home is located within the zone. Each VNZ is
designed in the same way and manner as an HNZ. For example, VNZ
115-1 surrounds IBS and antenna site 130-1 and VNZ 115-2 surrounds
IBS and antenna site 130-3 in the same way as HNZ 105-1 surrounds
IBS and antenna site 130-2.
[0039] The subscriber to LCS service need not select a VNZ for
their service that is proximate to or overlaps their HNZ.
Subscriber MS 10, for example, may choose VNZ 115-1 or the more
remote VNZ 115-2 or both zones in addition to their HNZ 105-1. The
subscriber, thus, may choose a VNZ 115-2 that is considerably
remote from their HNZ such as a zone surrounding their place of
employment, their school or the neighborhood of a family member.
The VNZ selected may be a VNZ so remote from their HNZ that a call
from their HNZ to the VNZ might be a toll call if it were a wired
line PSTN service call.
[0040] When subscriber MS 10 roams from HNZ 105-1 into VNZ 115-1 by
way of the labeled buffer zones, there will be no charge for
airtime and the call in progress will be maintained. When
subscriber 10 roams from HNZ 105-1 into VNZ 115-2, then, there is
no overlapping buffer zone, the call in progress may or may not be
maintained. If the LCS subscriber happens to be also a public
PCS/Cellular service subscriber, the call in progress is handed
over to the public PCS/cellular system using public cellular
spectrum frequency, there will be no air time charges for the
duration of the same call. There exist at least three alternative
embodiments for the subscriber 10 that travels outside an HNZ or a
VNZ to which they have subscribed. These include 1) allowing the
subscriber to continue the call they have initiated or have
received without additional charge at least for a predetermined
length of time, 2) disconnecting the subscriber from the connection
they have for a given call after the subscriber leaves their HNZ or
subscribed-to VNZ's or 3) allowing the call to continue outside
their HNZ or subscribed-to VNZ's and billing the subscriber for the
air time. When the subscriber is within the third alternative, the
subscriber may receive a conventional wireless service such as
DPCS. As a subscriber reaches a borderline of a subscribed-to zone,
the subscriber may see a lit warning lamp, and/or receive an
audible or other alert to their status as is further described in
copending application, U.S. patent application Ser. No. TBD,
entitled, "Automatic Status Indicators for Neighborhood Cordless
Services," filed on the same day as the present application and
invented by A. Chow, R. Miller II, J. Russell, W. Ying, and S.
Wang.
[0041] The buffer zone is inherent to each HNZ or VNZ. It is the
area that defines the perimeter of the zone where service quality
may not be at the optimal level, but service can still be rendered.
(NOTE: "buffer zones" also exists in cellular/DPCS, they are just
the periphery of a cell, the buffer zone is not unique to LCS.)
[0042] Intra-building Utilization of HNZ and VNZ, for example, by
an Employer
[0043] The concept of HNZ and VNZ can be extended to providing an
intra-building or intra-office complex LCS. LCS can be used to
provide wireless intra-building communications. A home zone may be
one location of a company and visiting zones may be frequently
visited locations of the same company within the same company
premises or another company premises. Service may be provided at
one rate for all wireless use of a company owned phone or phone
system at a company location. Moreover, in the spirit of U.S. Pat.
No. 4,456,793, hereby incorporated by reference in its entirety,
the service may be extended to comprising, for example, an infrared
light link between the phones and the IBS and antenna sites. In one
embodiment of LCS within a building, different floors of the
building, hallways and certain radio frequency shielded or isolated
rooms may be equipped with IBS and antenna sites. For example, one
sector of one floor may be distinguished from a sector of another
floor, if appropriate and depending on the application.
[0044] System Architecture
[0045] The LCS system architecture will now be described in further
detail with reference to FIG. 1. The subscriber's MS 10 may be
equipped with a typical DPCS or WS mobile telephone. A DPCS
telephone in compliance with IS-136 is preferred in the present
invention. Certain enhancements to the basic IS-136 design include
audible, light (such as LED), and/or other means of alerting a
subscriber of a change in service and/or other status. Without
limiting any invention, and by way of example, a set of LEDs may
present colored indications of red for no service, a green light
for service A, such as conventional cellular or PCS service, a
brown light for cellular roaming service and a blue light for
service B, the LCS service. By "no service" is intended those times
when the mobile telephone is powered and has received a user
request, but the mobile station is not able to establish a
connection with any service provider. When a subscriber is in their
HNZ or VNZ, the station may first try to establish an LCS
connection and if not possible, due to low signal strength or
because the subscriber is out of a zone, the mobile station will
try to establish a conventional WS, PCS or DPCS connection, and
also can not establish a connection to these systems.
[0046] Another enhancement is the capability for the mobile phone
to automatically select the appropriate service provider for the
given coverage area. For example, if a customer is a subscriber to
both cellular/DPCS and LCS service, it would be cumbersome for the
user to remember when to select the correct service profile on
their MS (for example, such as the IS-136 Number Assignment Module
(NAM) A for cellular/DPCS service, and NAM B for LCS service.) The
mobile phone working in conjunction with the cellular/DPCS or LCS
network intelligence will determine the correct service profile
(e.g., IS-136 NAM) that should be active thus permitting the user
to transition between services seamlessly and accurately.
[0047] A user subscribes to multiple wireless services and the MS
stores the service specific information (e.g., IS-136 NAM) to
access the appropriate network. The network(s) associated with all
the subscribed services also maintains a database including the
subscriber's profile, service subscription, service preferences and
priorities. In particular, the NSP for the HNZ of the subscriber
maintains a subscriber profile that identifies all the
subscribed-to services for the subscriber and, for local cordless
service, their selected home and neighborhood zones. The subscriber
profile identifies what radio channel is allocated to a subscriber
at a particular time. The NSP also maintains a service profile that
for each service maintains a table of available frequencies and
frequencies for adjacent NSP's and zones or cells. When the
customer enters a coverage area and turns on their Mobile Station
(MS), the MS remembers the last service environment it registered
and attempts to use the same profile with the current network. The
network recognizes the customer and retrieves the subscriber
profile from the database. Based on the user's current location
information, the network determines the preferred service profile
for the user. If the current coverage area offers the preferred
service environment, the network accepts the registration and the
MS is ready for service. If the preferred service environment is
available in the coverage area but under another MS service
profile, the network directs the MS to switch to that service
profile. The MS retrieves the correct service profile data and
registers for the new services. If the MS is about to move to
another zone or a service, then the NSP has to compare the
subscriber profile to the service profile and adjacent service
profiles of adjacent NSP's to be sure that the subscriber may
receive service and a channel. These services can be offered by the
previously attempted network or by a new network. In either case,
the (previously attempted or new) network will again determine if
the user is in the correct service environment and using the right
profile. If so, the network accepts the registration, the MS
informs the subscriber of service (audibly and/or visually), and
the subscriber begins to use the service.
[0048] Referring to subscriber 10 located in HNZ 105-1, there is
shown an intelligent base station (IBS) and antenna site 130-2 at
the center of the HNZ 105-1 with which subscriber 10 communicates
via their DPCS or WS mobile station. The IBSs 130-1, 130-2 and
130-3 each may comprise a digital software radio station that
supports an IS-136 based time division multiple access (TDMA)
common air interface. For example, each IBS may support three TDMA
frames (this comprises of eight IS-136 digital traffic channels, a
digital control channel) and four ISDN-BRI (basic rate interface
2B+D) lines for providing up to eight simultaneous telephone calls.
Again by way of example, respective links 135-1 and 135-2 may
couple IBS and antenna sites 130-1 and 130-2 to remote terminals
(RT) (only a single RT 180 is shown by way of example), for traffic
concentration or relay of the calls to a local subscriber switch
(LDS) 140-2 via a GR 303 trunk interface 185, as appropriate.
GR-303 relates, for example, to a known remote digital terminal
(RT) to local switch interface comprising an integrated digital
loop carrier system and associated requirements. In an alternative
embodiment, the IBS 130-3 may communicate directly via ISDN BRI
link 135-3 to a local subscriber switch 140-1.
[0049] LDS 140-1 or 140-2 may preferably comprise any digital local
switch known in the art including, but not limited to, a No. 5 ESS
switch manufactured by Lucent Technologies, Inc., or a DMS-100
switch manufactured by Northern Telecom. These switches perform the
switching function necessary to connect LCS subscribers to PSTN
customers, WS customers, PCS or DPCS customers or other LCS
subscribers wherever situated. A network server platform (NSP)
(e.g., NSP 145-1, 145-2) of an LCS system may be an adjunct to each
LDS 140-1 and 140-2. The NSP may preferably comprise a pair of
fully redundant (i.e., for hot standby fault tolerance) Sun Sparc
work stations available from Sun Microsystems or other comparable
processor programmed as will be further described herein for
registration, call processing, and/or call hand-off. Each NSP will
have an intelligent database (ID) containing subscriber profile
information. Each site may be backed-up by an intelligent spare NSP
and ID and program memory backed up on disc or other memory
back-up. In FIG. 1, LCS subscriber switch 140-2 is coupled to NSP
145-1 and LCS subscriber switch 140-1 is coupled to NSP 145-2. Each
NSP operates to effectively control all activities associated with
subscriber registration, call setup and tear down, radio frequency
engineering, handoffs, feature applications, and operation,
administration and maintenance (OA&M) functions. Each
respective NSP for a LCS subscriber switch manages all its
subtending IBS's and antenna sites. In the depicted example, a
single LCS subscriber switch 140-2 and NSP 145-1 may serve multiple
neighborhood zones, in this instance, HNZ 105-1 and VNZ 115-1. The
number of zones served by a single NSP need not be limited to two
but may comprise 3 or more.
[0050] Preferably, all NSP's are linked together for communication
via, for example, an IP-based LCS intranet or virtual private
network (VPN) comprising of a router 165. During operation, the
IP-based network is utilized for passing call and subscriber
registration, mobility management and LCS Operation Administration
& Maintenance (OA&M) related information. Also coupled via
the IP-based intranet or VPN are connections to an authentication
center (AC) 190, to a LCS Customer Service Center (CSC) 160, a
network management and operations center, and a operations support
systems center.
[0051] Each NSP may have an associated intelligent database (ID).
For example, intelligent database 146-1 is associated with NSP
145-1. The ID may store LCS subscriber profiles, which includes
information regarding each LCS subscriber within the HNZ, such as
subscribed features and/or calling preferences. The ID also uses
the information for communication with other ID's in the event the
subscriber has roamed to a VNZ not handled by the associated NSP.
For example, in ID 146-1, there would exist subscriber profiles for
all subscribers in neighborhood zones 115-1 and 105-1.
[0052] The LCS Customer Service Center (LCS CSC) 160 may provide a
human or automated service representative interface to any
potential or existing subscriber. Typically, the LCS CSC may
comprise a known service representative position system or voice
response system. The LCS CSC supports at least service activation
for subscribers to LCS service and administration of service (for
example, facility, trouble and billing queries).
[0053] The LCS authentication center (AC) 190 may be a shared
resource of the LCS network as is the LCS CSC 160. As will be
further described herein, a subscriber to LCS may preserve their
directory numbers (DN) if they disconnect their wired PSTN number
and connect to LCS service. The LCS AC 190 may utilize IS 136
cellular authentication voice encryption (CAVE) to assist in
validating and authenticating subscribers and to provide voice
privacy and encryption capabilities. ACAC Gateway (GW) 170 sits
within the IP-based LCS intranet or VPN 110 and provides a TCP/IP
data link to the SS7 network 120. This IP-based network, as
explained above, provides access to and interworks with the home
location register for registration of MIN-based LCS subscribers for
delivery of calls, for example, from subscriber 150 to LCS
subscribers within the neighborhood zones 115-1, 115-2 and 105-1.
The GW 170 is responsible for the TCP/IP to SS7/TCAP protocol
conversion between the SS7 network and the LCS network. GW 170 is
also responsible for global location management on a per NSP 145
location basis for, for example, MIN-based call delivery.
[0054] For this invention, we use the radio frequency
self-configuration algorithm known in, e.g., U.S. Pat. Nos.
5,809,423 (issued Sep. 15, 1998), 5,787,352 (issued Jul. 28, 1998),
5,740,536 (issued Apr. 14, 1998), 5,513,379 (issued Apr. 30, 1996),
5,404,574 (issued Apr. 4, 1995), and 5,345,499 (issued Sep. 6,
1994), all issued to B. Mathilde et al., and all hereby
incorporated by reference in their entireties. This algorithm is
designed to sniff and designate unused and interference-free
traffic and control channels (such as IS-136 Digital Traffic
Channels and digital control channels) from the public
macrocellular network for use by an underlying/stacked cell use.
The algorithm will also be able to detect when the public
macrocellular network begins to use these channels, and will
automatically adjust by re-selecting another unused frequency. This
algorithm greatly simplifies the radio frequency engineering and
deployment processes. Without this algorithm, the LCS service will
need to reserve radio frequencies specifically for LCS use.
[0055] The Intelligent Base Station (IBS) and Antenna Site
[0056] The intelligent base station (IBS) can be any currently
existing radio base station that is known in the art. The IBS
should be capable of performing automatic frequency allocation
functions, which are known in the art. For this invention, the
preferred embodiment is via self-configuration, as described by
U.S. Pat. No. 5,724,665 describing an intelligent wireless
communication base station. Other U.S. Patents useful in its design
include U.S. Pat. Nos. 5,608,708; 5,592,470; 5,574,775 and
5,406,615. Referring to FIG. 2, there is shown a generalized
software radio architecture for an IBS 130 shown in FIG. 1. Line
201 may be an ISDN BRI line as shown or other equivalent data line.
Line 201, although not shown, may be coupled via a remote digital
terminal 180 to a switch 140 or directly to the switch per FIG. 1.
Remote digital terminal 180 provides concentration of lines. Line
201 is connected to a communications processor of processing module
270. Communications processor 272 handles all wire line interface
control functions. The communications processor is coupled to a
network compatibility processing module for handling incoming and
outgoing calls requiring either LCS or DPCS or other network
compatibility. Main controller 274 is coupled to a source/error
correction coding/decoding module 230 and a channel coding module
240. A frequency reference or clock 276 is divided to provide all
the reference frequencies needed by any other module including
channel coding module 240.
[0057] Associated with main controller 274 is variable memory 280,
core program memory 285 and critical parameter memory 290. Program
executable software and data are stored in variable memory 280.
Boot code and compressed executable code are stored in core program
memory 285 and non-volatile data are stored in critical parameter
memory 290.
[0058] Network compatibility processing module 220 comprises a
coding engine 222 and a decoding engine 226. Source/error
correction coding module 230 comprises a digital signal processor
232 and coder algorithm for encoding and a digital signal processor
236 and decoder algorithm 236 for decoding. The channel coding
module 240 contains a digital signal processor 242 for interfacing
with the radio frequency processor 250 and includes a
modulator/demodulator 244.
[0059] Radio signal processing module 250 provides for changing the
frequency, power and bandwidth requirement of an RF channel via
software. One IBS 130 is constantly in communication with its
neighboring IBS's to determine their signal strengths, frequencies
and bandwidths via NSP 145. A particular IBS builds a map of its
overlapping buffer zones with other IBS's that is frequency and
bandwidth dependent so that real time hand-offs can occur between
zones and IBS's without disruption of service. Digital radio
processing via controller 274 operation with module 250 provides a
reduction in the number of radio units per base station, increased
spectrum efficiency, improved data service performance and supports
dynamic speech compression. Phase shift keying (PSK) or quadrature
amplitude modulation (QAM) modulation in a variable TDM (time slot
based) structure is preferred. The channel bandwidth and time slots
may vary from 30 KHz to a maximum rate based on intersymbol
interference. In practice, channels at 200 kHz are possible. In an
IS 136 environment, the channel bandwidth may comprise integral
multiples of 30 kHz. The number of frames assigned to a particular
intelligent base unit 130 may vary dynamically depending on the
data requirements. The frame structure may facilitate
retransmission of IS 136 frames where the present base station may
relay encoded speech to a larger area or macro base station. The
latter may determine the total data required for a group of IBSs
130 that it serves and choose the appropriate number of frames,
time slot assignments and RF channel frequency, power levels and
bandwidth. The spectrum allocations may be managed from such a
central location as a macro cellular base station or in a preferred
embodiment such as the NSP 145 maintaining the service profiles,
power levels, frequencies, badnwidths and the like and downloaded
to IBS 130 in real time.
[0060] Module 250 contains a digital up converter 252 and a digital
down converter 254. When up converting, the output is fed via a
mixer 261 to an amplifier 262 for outputting via antenna 267 via
filter 263. On the antenna receive side, the received signal is fed
via filter 263 and amplifier 264 to mixer 265 and the result passed
to digital down converter 254. Frequency synthesis circuit 266
provides frequencies at whatever channel frequencies are utilized
at a particular point in time.
[0061] Antenna 267 may be a sectorized antenna system in one
embodiment collecting and radiating energy in 800 MHZ and 1800 MHZ
spectra or other suitable spectra. Each zone 105-1 may comprise
several such as three sectors or small cells such that an
intra-cell hand-off may be required (as will be discussed in
connection with FIG. 6a).
[0062] Flexibility in Addressing a Subscriber
[0063] An LCS subscriber may elect to discontinue their current
PSTN directory number (DN) and use that same number as their LCS
address (i.e., Local Number Portability--LNP). Alternatively, the
LCS subscriber may receive a new LCS directory number. A third
option is for the LCS subscriber to use the mobile identification
number (MIN) the subscriber may have as a subscriber to wireless
cellular services or personal communications services.
[0064] On the air interface side, in this embodiment, each IBS has
9 full-rate TDMA channels. Note: Number of full rate channels for
the IBS should be made as a variable for this patent, since the
number of radio channel per radio port can be designed according to
different services applications and coverage density requirements.
IBS can provide as many radio channels as long as it meets the
design and service deployment financial criteria. Among these
channels, one full-rate channel will be designated as the Digital
Control Channel (DCCH) and the remaining 8 channels will be used as
the Digital Traffic Channel (DTC). In order to support up to 8
simultaneous conversations, for instance, four ISDN-BRI lines may
be used to connect the IBS 130 to the LCS local switch 140 (FIG.
1). Therefore, an IBS with 8 DTCs can support up to 8 simultaneous
calls. When a user subscribes to the LCS services as a DN-based
user, the subscriber will be given a DN during service activation
(that is, each DN is assigned with a TEI designated to an IBS) and
the MS is in effect assigned to a specific IBS in the subscribed
HNZ for call delivery purposes. For example, subscriber 10 will be
assigned to IBS 130-2.
[0065] Referring again to FIG. 1, since IBS 130 will be connected
to an LCS local digital switch such as the No. 5 ESS or DMS-100
digital switch 140, a DN based network switching element, the call
routing between the local switch and the IBS must also be DN-based.
The LCS service may use Cellular/DPCS RF infrastructure that is a
MSC/MIN based switching platform. Therefore, these two different
switching algorithms creates alternative call delivery scenarios
for LCS calls. Consider the following LCS call delivery
scenarios:
[0066] When a MIN-based LCS subscriber enters an LCS coverage area
and receives an incoming call, the local digital switch 140 will
not deliver a MIN based call (that is, only an MSC does it). The
local NSP, for example, NSP 145-1 dynamically assigns a DN that
belongs to the IBS 130-2 that MS 10 is currently registered to
deliver the call.
[0067] When the PSTN delivers a call to a DN-based MS, the local
digital switch 140 routes the call to the IBS associated with that
DN. If the MS is registered with another IBS (which may be referred
to as a Target-IBS or T-IBS which could be located in VNZ/HNZ) at
that time, the IBS works with the NSP and the local switch to
transfer the incoming call to an NSP dynamically assigned DN
supported by that T-IBS.
[0068] However, if these dynamically assigned DNs as described from
the above scenario are assigned previously to a subscriber as a
permanent DN, then the LCS system will not immediately be able to
deliver the incoming call for lacking of the DN necessary for the
local switch to process the incoming call. Two out of the 8 DNs of
each IBS's 4 ISDN/BRI lines will be reserved for this purpose and
used only for call processing purposes by the local switch. These
dynamically assigned DNs should not be assigned to any subscriber.
These dynamically assigned DNs from each IBS will be referred to
herein as the call Forward DNs (FDNs). The FDNs will be used for
MIN-based call delivery and DN-based roaming capabilities. FDNs are
transparent to the end-users; they are used internally by the LCS
system. When the local switch delivers a call to a MIN-based or
visiting DN-based MS, after the NSP locates the MS, the NSP assigns
an FDN from the currently registered IBS to the MS in order for the
local switch to terminate the call.
[0069] PSTN call delivery of DN-based mobiles can also occur using
the Advanced Intelligent Network. All DNs associated with DN-based
mobiles have triggers set on the digital switch such that when the
digital switch 140 receives the call the switch requests additional
routing instructions from the NSP. The NSP pages the MS to
determine its current location, T-IBS. If the MS is registered in
its home IBS, the NSP directs the switch to complete the call to
the DN. If the MS is registered in another IBS, the NSP assigns an
available FDN from T-IBS and directs the switch to forward the call
to the T-IBS/FDN.
[0070] Numbering Schemes
[0071] As already introduced above, there exist three numbering
options for LCS services: 1) Use an existing cellular/DPCS MIN,
2)Use a new DN or 3)Use a ported ILEC DN (the subscriber's former
wired PSTN service telephone number ported from the local exchange
carrier).
[0072] Call routing differs slightly between a DN-based MS and a
MIN-based MS because the MIN-based MS requires interaction with the
HLR while the DN-based MS does not.
[0073] Numbering Scheme One: Mobile Identification Number
[0074] In this addressing scheme option, the new LCS subscriber is
an existing wireless service (WS) customer and desires to keep the
same MIN for their new LCS services. These subscribers will be
identified in this document as MIN-based LCS subscribers.
[0075] Numbering Scheme Two: LCS Service Provider Assigns New LCS
Phone Directory Number
[0076] In this addressing scheme option, the new subscribers may or
may not have an existing IS-136 phone. However, a DN will be
assigned by local service representatives. The DN may be programmed
into the IS-136 phone via IS-136 based Over-the-air Activation
Teleservice (OATS), described subsequently herein. These
subscribers will be identified in this document as DN-based LCS
subscribers.
[0077] Numbering Scheme Three: Ported Local ILEC DN
[0078] LCS subscribers who give up their conventional wired service
can port their existing residential landline phone numbers (i.e.,
from their local exchange carrier, ILEC) to LCS services. The DN
can be programmed into the IS-136 phone via IS-136 based OATS.
These subscribers will be identified in this document also as
DN-based LCS subscribers.
[0079] The Process of Actuating an LCS Subscriber
[0080] A new LCS subscriber may purchase a MS apparatus at a retail
outlet, preferably, an IS 136 compliant mobile station set with a
display. The new subscriber then dials a telephone number provided
for customer service center (LCS CSC) 160 and is connected to a
service representative or a voice interactive response unit known
in the art. Either the device or a service representative may
welcome the new subscriber's call and thank the new subscriber for
subscribing to LCS. Either may then request of the subscriber their
personal data which may be verified by known processes. The new
subscriber is requested to particularly select an option for
addressing: 1) do they wish to disconnect their wired PSTN service
and reuse the associated DN, 2) obtain a new LCS number or 3) use
their MIN from an existing mobile wireless service. The subscriber
is also advised of the rate selection opportunities and boundaries
of neighborhood zones they may be interested in.
[0081] The LCS CSC 160 then processes and temporarily stores all
subscriber information in a subscriber profile including such
information as selected home neighborhood zone, visiting
neighborhood zone(s) they have subscribed to, calling features, the
make and model and electronic serial number of the subscriber's MS,
and billing address and payment information. All the related
subscriber service profile data will be populated into the LCS CSC
database and communicated, for example, by the IP-based intranet or
VPN to populate a database at LCS authentication center (AC)
190.
[0082] Once the new subscriber is validated and their profile
completed, the LCS CSC 160 generates a unique data word that the
subscriber will use later to actuate service referred to herein as
a feature code. Also, a personal identification number which may be
of the new subscriber's choice may be mutually agreed upon and
stored. The feature code and/or PIN in combination will be given to
the new subscriber so they may actuate their LCS service
automatically via a self-activating process to be referred to
herein as over-the-air activation teleservice (OATS). The
subscriber profile including PIN is further downloaded, in a
preferred embodiment, via the IP-based intranet or VPN to
intelligent databases 146 for their HNZ and any VNZ to which they
have subscribed. For example, subscriber 10 may be a subscriber to
HNZ 105-1, VNZ 115-1 and VNZ 115-2. In such an instance, the
subscriber profile will be provided to intelligent databases 146-1
and 146-2.
[0083] Henceforth in the detailed description of the invention,
call registration, call processing and call hand-off features will
be described in FIGS. 3-7 with reference to generic elements, for
example, switch 140 or specific elements such as switch 140-1 with
not intention to be limited by the use of the specific elements of
FIG. 1. The invention is not limited by the specific arrangement of
elements of FIG. 1. However, the reader may find the specific
references useful in understanding call processing functions from
the viewpoint of one example of an LCS subscriber 10.
[0084] NAM downloading and a Self-Actuating LCS Service (OATS)
[0085] In order for the subscriber to actuate their LCS service,
they must be in their selected HNZ. For example, new subscriber 10
must be in the boundaries of their HNZ 105-1. Subscriber 10 then
turns on their MS and enters their feature code and/or PIN. (The
PIN may be used in a similar manner to the manner that PIN's are
presently used in wireless services generally, namely, to promote
call security and prevent service piracy and, consequently, may be
optional). The preamble consists of the MS locking onto the IBS
130-2, transmitting an IS-136 Origination message including the
feature code/PIN to the IBS 130-2 and IBS 130-2 forwarding the
message via RT 180, GR303 link 185, and local switch 140-2 to its
associated intelligent switch controller (NSP) 145-1. Since the ID
146-1, after the subscriber sign-up process is completed, they
should have the subscriber profile stored for that subscriber
including their feature code and/or PIN, the NSP 145-1 validates
the MS by comparing the entered feature code and/or PIN with data
stored in the ID 146-1. A further validation may include the
comparison of a collected electronic serial number of the MS with
an associated database entry. If there is no match of all or any of
the two (or three), a message may be returned to suggest the
subscriber contact LCS CSC 160. After the NSP 145-1 verifies that
the subscriber profile is in the ID 146-1, it initiates OATS to
activate the MS by sending the Configuration Data Request message
to the MS via IBS 130-2. The MS responds with Configuration Data
Response to the NSP 145-1 via IBS 130-2. Altogether the preamble
and the configuration data request and response comprise process
step "a" shown.
[0086] As shown in FIG. 3 step b, once a download request message
is received by MS, a download response requesting a download is
transmitted to NSP 145-1. This message includes a request for the
downloading of all algorithms and data necessary for LCS service
including a number assignment module (NAM) giving the MS its
subscriber opted-for address (MIN or DN). After the NSP receives
the download response message, step "c" begins and a NAM commit
request message is transmitted to the MS. This message instructs
the MS to program/populate and commit a designated number
assignment module area of memory (NAM(x)) with the downloaded data.
If a subscriber decides to use their directory number as the number
to be called, NAM(x) will be designated for LCS DN programming, and
likewise if the subscriber decides to use their MIN as their reach
number, NAM(x) will be designated for LCS MIN programming. Now the
registration processes will be discussed for each of the options of
MIN or DN based LCS service and when either must register in a
visiting neighborhood zone to which the subscriber has subscribed.
These processes are carried out in real-time.
[0087] Registration Process for a MIN-Based MS
[0088] Referring to FIG. 4a, there are shown steps "a," "b," "c"
and associated with registration processes for a MIN-based
subscriber in their home neighborhood zone. In step "a", the DCCH
process consists of IBS 130 broadcasting system-wide and IBS 130
specific parameters (such as system and IBS 130 identification) on
its DCCH and the MS 10 locking onto the DCCH when the MS 10 powers
up. The MS 10 sends an IS-136 registration message to the IBS 130.
IBS 130 forwards the registration message to its associated NSP 145
via the LCS local switch 140. This message contains IS-136
registration data.
[0089] In step "b," the home zone NSP 145 checks the MS's status
with its Intelligent Database (ID) 146 and determines that the MS
is a valid MIN-based LCS service subscriber. Since the MS is
MIN-based, NSP must interact with the WS HLR for the registration
process. If the optional MS authentication is required (this is
determined by the LCS service provider and indicated to the MS 10
as one of the DCCH broadcast parameters), the MS IS-136
Registration message will include the authentication information.
The NSP 145 will initiate the authentication procedure with LCS AC
140 by sending an authentication message via router 165. The NSP
145 sends an IP-based message containing IS-41-like authentication
information to the LCS AC. After successful authentication of the
MS, the LCS AC sends an IP-based IS-41-like authreq message back to
the NSP 145.
[0090] In step c, after successful MS authentication, or if no
authentication is required, NSP 145 must register the MS 10 by
sending a registration message to the WS HLR 175-2 via gateway 170
to update the MS's new location for call delivery purposes. The NSP
145 sends a TCP/IP-based message containing IS-41-like registration
information to the TCP/IP to SS7 Gateway (GW) 170. The GW 170
receives the registration message which also includes the NSP's
unique IP address, translates the message into an SS7/TCAP/IS-41
REGNOT message and sends it to the HLR 175-2.
[0091] After a successful registration, the HLR 175-2 sends an
SS7/TCAP/IS-41 regnot message back to the GW 170. The GW receives
the IS-41 regnot message, translates the message into a TCP/IP
based registration accept message. Since the GW 170 stores each NSP
145 unique IP address based on information gathered during MS
registration message, the GW sends the registration accept message
back to NSP 145 based on the NSP's unique IP address. The NSP 145
processes the registration accept message and sends it to the IBS
130. NSP 145 notes that the mobile is successfully registered and
active.
[0092] In step d, the IBS 130 sends an IS-136 Reg. Accept message
to the MS 10 to complete the MS registration procedures.
[0093] There are two possibilities when a MIN-based MS 10 registers
in a VNZ 115. The first one is where the VNZ and the HNZ are
covered by the same NSP (cell 101-2 in FIG. 1 comprising HNZ 105-1
and VNZ 115-1). The second is where the VNZ and the HNZ are covered
by different NSPs (HNZ 105-1 and VNZ 115-2). As far as the LCS
system is concerned, both MIN-based registration signaling flows
are the same as discussed in the previous section (MIN-based MS
registered in the HNZ). The HLR 175-2 is updated when the latest
registration location occurs regardless of whether the MS 10 is in
the HNZ or the VNZ.
[0094] Registration Process for a DN-Based MS
[0095] Referring to FIG. 4b, there is depicted the signaling flow
scenario of an MS that uses an assigned directory number (DN) or a
ported ILEC DN as the number to be used in the subscribed-to
neighborhood LCS zones. Since the MS is DN-based, there is no
requirement for interaction with an HLR 175-2 during registration.
During service activation, the subscriber's profile is downloaded
to every NSP/ID that covers the subscribed-to zones, the HNZ and
any subscribed-to VNZs. The subscriber has already activated the
LCS service via OATS.
[0096] The signaling flow shown in FIG. 4b describes the scenario
where a DN-based MS 10 registers that requires just two steps "a"
and "b." In step "a," the DCCH process consists of H-IBS 130
broadcasting system-wide and H-IBS 130 specific parameters (such as
system and H-IBS 130 identification) on its DCCH and the MS locking
onto the DCCH when the MS powers up. The MS sends an IS-136
registration message to the home zone H-IBS 130. The H-IBS 130
forwards the registration message to the H-NSP 145 via the LCS
local switch 140. This message contains IS-136 registration
data.
[0097] In step "b," the H-NSP 145 checks the MS's status with the
Intelligent Database (ID) 146 which already has the subscriber
profile, determines that the MS 10 is a valid DN-based LCS
subscriber. If the optional authentication procedure is required
(as determined by the LCS service provider), the H-NSP 145 sends an
IS-41-like AUTHREQ message in IP format to the LCS Authentication
Center (AC) 190 in order to authenticate the mobile. When the
authentication process is successful, the AC 190 returns an
authentication response message to the H-NSP 145. The H-NSP 145
sends the reg. accept message to the H-IBS 130. The H-IBS 130 sends
an IS-136 Reg. Accept message to the MS to complete the MS
registration procedures.
[0098] When a LCS subscriber roams or otherwise moves to a
subscribed-to visiting zone, as far as the subscriber is concerned,
the same DN number will be used for all call delivery (i.e.,
roaming-like situation). A dynamically assignable FDN, described
previously, is used to terminate the call.
[0099] Referring to FIG. 4c, three steps are required to process a
registration of a DN-based MS 10 in a VNZ. In step "a," the DCCH
process consists of V-IBS 130-3 broadcasting system-wide and V-IBS
130-3 specific parameters (such as system and V-IBS 130
identification) on its DCCH and the MS locking onto the DCCH when
the DN-based MS powers up. The MS 10 sends an IS-136 registration
message to the visited V-IBS 130. V-IBS 130, for example, V-IBS
130-3, forwards the REG. REQUEST message to the V-NSP 145-2 via the
LCS local switchl40-1. This message contains IS-136 registration
data.
[0100] In step "b," the V-NSP 145-2 checks the MS's status with the
Intelligent Database ID 146-2 which has the subscriber profile
previously downloaded by the LCS CSC 160 and determines that the MS
is a valid DN-based LCS subscriber. The V-NSP 140-1 sends an
IS-41-like authreq message in IP format to the AC 190 for
subscriber authentication. The AC190 validates the subscriber with
its internal database and returns an authreq response message back
to the V-NSP 145-2.
[0101] In step "c," the V-NSP 145-2 sends a registration
notification message to H-NSP 145-1 to indicate the new location of
the MS for proper delivery of incoming calls to the MS. The H-NSP
145-1 records the current MS location as being in a subscribed-to
visiting zone 115-2. The H-NSP 145-1 sends a reg. notification
response message to the V-NSP 145-2. In return, the V-NSP 145-2
sends registration accept message to the V-IBS 130-3. V-IBS 130-3
sends an IS-136 Reg. Accept message to the visiting MS to complete
the registration process.
[0102] Call Delivery to an LCS Subscriber
[0103] Call processing of a call to or from a subscriber visiting a
neighborhood zone involves the utilization of one, two or more
reserved forwarding directory numbers (FDN's) in the visited zone.
For example, the subscriber MS 10 that visits VNZ 115-2 will be
dynamically assigned one of these reserved FDN's while they are in
the visited zone. These same FDN's may be used by another
subscriber when that subscriber visits the zone from their home
zone after the first subscriber no longer needs it.
[0104] The call delivery process from an originating switch in the
PSTN 100 to a MIN-based LCS subscriber are shown in FIG. 5a. To the
extent possible, similar reference characters are borrowed from
FIG. 1 to represent similar elements for an incoming call to
subscriber MS 10. Process step "a" takes the incoming call request
to the home zone NSP 145-1. The PSTN switch 140-3 of PSTN 100
processes the MIN-based incoming call and sends an ISUP Initial
Address Message (IAM) to a PSTN-based MSC 180. The MSC 180 provides
services and coordination between mobile users in the public
cellular network and between the mobile users and the external
network such as PSTN 100. When a PSTN user dials a MIN, the PSTN
local switch LDS will always route the call to the MCS switch for
call delivery. One way to look at the phone networks including PSTN
100, public cellular network and LCS is that all the switches from
each network are fully connected and they all have connection to
the Common Signaling Network Number 7 (SS7). The Mobile Switching
Center, MSC 180, provides switching functions for the cellular
network and coordinates the establishments of calls to and from
cellular/DPCS subscriber. The MSC interfaces with the cellular
network(s) and the public switch networks. Since the MSC does not
have the MIN-based user currently registered, the MSC sends a
SS7/TCAP/IS-41 location request (LOCREQ) message to HLR 175-2. The
HLR 175-2 knows the current registration location of the MIN-based
MS because of prior registration notification from the home zone
NSP (H-NSP) 145-1 via the gateway (GW) 170. HLR 175-2 sends a
SS7/TCAP/IS-41 route request (ROUTREQ) message to the H-NSP 145-1
via the GW 170 for routing instructions to the MS 10. The GW 170
translates the message to an IP message and sends it to the H-NSP
145-1 (ROUTE REQ (MIN)). This completes process step "a".
[0105] Process step "b" involves letting the MSC 180 know the
result. The H-NSP 145-1 verifies that the MS 10 is still registered
in the home zone and is presently idle. H-NSP 145-1 reserves an
available forward directory number (FDN) and a B-channel for its
transmission in the home zone IBS (H-IBS) 130-2. Then, H-NSP 145-1
returns a route request response message including the reserved FDN
to the GW 170. If no FDN is available, of course, the H-NSP 145-1
rejects the request. Continuing a favorable call-completion
scenario, the GW 170 translates the IP message to a SS7/TCAP/IS-41
routreq response message and sends it to the HLR 175-2. This
completes process "b".
[0106] Process step "c" takes the call from HLR 175-2 to a set-up
request of H-IBS 130-2. The HLR returns the reserved FDN
information in the IS-41 TCAP locreq response message to the MSC.
The MSC 180 initiates call setup by sending an ISUP IAM message to
the LCS switch (LDS) 140-2 based on the FDN. The LCS switch (LDS)
140-2 sends a Q.931 call setup message to the H-IBS 130-2 based on
the reserved DN. This concludes process "c".
[0107] Process step "d" relates to acknowledgment. The H-IBS 130-2
sends a call request message to the H-NSP 145-2 to validate the
call request. Note: H-NSP 145-1 may initiate IS-136 authentication
procedure when necessary. The H-NSP 145-1 uses the ID database
146-1 to locate the record of FDN-to-MIN mapping to validate the
call. If the request is valid and RF resources are available, H-NSP
145-2 will reserve a digital traffic channel (DTC) for call
delivery. H-NSP 145-1 then sends a call request ack message with
the MIN, DTC, and B-channel (reserved when the FDN was assigned to
the call) to the H-IBS 130-2. If the call request is not valid or
no resources are available, the H-NSP 145-2 will return a call
request nack (stands for negative acknowledgment) and the H-IBS
130-2 will release the call. This concludes process "d".
[0108] In process step "e", the H-IBS 130-2 starts to page the
MIN-based MS 10. H-NSPH-IBS (Note: The IS-136 MS paging process is
as follows: the H-IBS 130-2 broadcasts an IS-136 page for the
MIN-based MS 10. The MS 10 must respond with an IS-136 page
response message within a specified time period. If the MS 10 does
not respond, the H-IBS 130-2 will release the call.) After the MS
10 successfully responds to the page, the H-IBS 130-2 sends a Q.931
call proceeding message to the LCS switch 140-2LCS.
[0109] In process step "f", the H-IBS 130-2 sends a DTC designation
message to the MS 10 and verifies the MS is on the DTC by
monitoring the returning DVCC code status change. After the MS 10
locks onto the DTC (DVCC status change), the H-IBS 130-2 sends an
IS-136 alert with info message to the MS 10 to initiate a ringing
indication to the user. H-IBS 130-2 also sends a Q.931 alert
message to the LCS switch 140-2. The LDS 140-2 sends an ISUP
address complete message (ACM) to the MSC to complete the
end-to-end call connection. The MSC 180 sends an ISUP ACM message
to the PSTN 100.
[0110] Process step "g" is similar to a cellular/DPCS connect
process. The LCS local switch 140-2 generates alerting (ring back
tone) to the originating user. When the MIN-based user 10 picks up
the call and the MS 10 sends an IS-136 connect message to the H-IBS
130-2, the H-IBS 130-2 sends a Q.931 connect message to the LCS
local switch LDS140-2. The LCS switch 140-2 sends an ISUP address
answer message (ANM) to the MSC. The MSC 180 sends an ISUP ANM
message to the PSTN switch 140-3, the PSTN switch 140-3 connects
the caller and thus the voice path is established and completes the
call delivery process.
[0111] Call Delivery to a DN-based Subscriber, the DN Being
Assigned for LCS
[0112] FIG. 5b describes the signaling flow scenario of a PSTN
caller dialing the LCS subscriber's DN when the DN is registered
with the H-IBS in the HNZ. In step "a," an originating PSTN switch
(somewhere in PSTN 100) processes the DN-based incoming call and
sends an ISUP LAM message to the HNZ LCS local switch (H-LDSH-LDS)
140-2 based on the DN dialed. The H-LDS 140-2 sends a Q.931 call
setup message to the H-IBS 130-2 based on the DN dialed. The H-IBS
130-2 sends a CALL REQUEST message to the H-NSP 145-1 to validate
the call request. The H-NSP 145-1 may initiate an authentication
procedure with an AC 190 when and if necessary.
[0113] In step "b," the H-NSP 145-1 validates the call by searching
the ID 146-1 and discovers that the MS 10 is registered in its home
IBS, H-IBS 130-2. If the request is valid and resources are
available, H-NSP 145-1 will reserve a DTC and a B-channel. H-NSP
145-1 then sends a call request ack message with the resource
information to the H-IBS 130-2. H-IBS 130-2 starts to page the
DN-based MS. If the call request is not valid or no resources are
available, the H-NSP 145-1 will return a call request nack and the
H-IBS 130-2 will reject the call.
[0114] The IS-136 MS paging process is as follows: the H-IBS 130-2
broadcasts an IS-136 page for the DN-based MS. The MS 10 must
respond with an IS-136 page response within a specified time
period. If the MS 10 does not respond, the H-IBS 130-2 will release
the call.
[0115] After successfully paging the MS, the H-IBS 130-2 then sends
a Q.931 call proceeding message to the H-LDSH-LDS 140-2. This
connects the B-channel to the H-LDS 140-2.
[0116] In step "c," the H-IBS 130-2 sends a DTC designation message
to the MS and verifies the MS is on the DTC by monitoring the
returning DVCC code status change.
[0117] In step "d," after the MS locks onto the DTC (DVCC status
change), the H-IBS 130-2 sends an IS-136 alert with info message to
the MS to initiate ringing indication to the user. It also sends a
Q.931 alert message to the LCS switch, H-LDS 140-2. The H-LDS 140-2
sends an ISUP address complete message (ACM) to the PSTN switch to
complete the end-to-end connection. The H-LDS 140-2 generates
alerting (ringback tone) to the originating user.
[0118] In step "e," when the DN-based MS user picks up the call,
the MS sends an IS-136 connect message to the H-IBS 130-2. The
H-IBS 130-2 sends a Q.931 connect message to the H-LDS 140-2. The
H-LDS 140-2 sends an ISUP address answer message (ANM) to the PSTN
switch, the PSTN switch connects the caller and thus the voice path
is established, completing the incoming call delivery process.
[0119] The called MS's DN may be registered with a visited V-NSP,
for example, V-NSP 145-2 in the VNZ 115-2. Referring to FIG. 5c,
step "a," the originating PSTN switch processes the DN-based
incoming call by sending an ISUP Initial Address Message (IAM) to
the H-LDS 140-2 based on the DN dialed. The H-LDS 140-2 sends a
Q.931 call setup message to the H-IBS 130-2 based on the DN dialed.
The H-IBS 130-2 sends a CALL REQUEST message to the H-NSP 145-1 to
validate the call request. The H-NSP 145-1 may initiate
authentication procedure when necessary with AC 190.
[0120] In step "b," the H-NSP 145-1 validates the call by searching
the ID 146-1 and discovers that the MS is currently registered in a
subscribed-to VNZ (V-NSP) 115-2. Consequently, H-NSP 145-1 sends an
IS-41-like ROUTREQ message in IP format to the V-NSP 145-2 for
routing instructions to the DN-based MS. The V-NSP 145-2 confirms
via ID 146-2 that the MS is still registered and idle in V-IBS
130-3. It reserves an available FDN from V-IBS 130-3, and returns a
route request response message including FDN to the H-NSP 145-1.
The V-NSP 145-2 also reserves a B-channel for the FDN. If no FDNs
are available, V-NSP 145-2 rejects the call which ultimately
results in rejecting the call to the originating user. The H-NSP
145-1 sends call req ack to the H-IBS 130-2 with an indication to
forward the call to the FDN from V-NSP 145-2.
[0121] In step "c," the H-IBS 130-2 sends a Q.932 facility message
to the H-LDS 140-2 to reroute the call to the forward FDN. The
H-LDS 140-2 sends the facility return result in a disconnect
message for response to the facility invoke message to the H-IBS
130-2; on receipt of the disconnect message, the H-IBS 130-2 sends
a release message to the H-LDS 140-2, and the H-LDS 140-2 sends a
release complete message in return. Immediately after sending the
disconnect message, the H-LDS 140-2 sends an ISUP LAM message to
the V-LDS 140-1 based on the FDN.
[0122] In step "d," the V-LDS 140-1 now has the call. The V-LDS
140-1 sends a Q.931 call setup message to the V-IBS 130-3 based on
the FDN. The V-IBS 130-3 sends a call request message to the V-NSP
145-2 to validate the call request. The V-NSP 145-2 may initiate
authentication procedures with AC 190 when necessary. The V-NSP
145-2 uses the ID 146-2 database to locate the record of FDN-to-DN
mapping to validate the call. If the request is valid, and RF
resources are available, the V-NSP 145-2 reserves the RF resource,
the DTC, for call delivery. The V-NSP 145-2 then sends a call
request ack message with the DTC and B-channel (reserved when the
FDN was assigned to the call) to the V-IBS 130-3. The V-IBS 130-3
starts to page the DN-based MS (the paging process is described
above in respect to FIG. 5b, step "b"). If the call request was not
valid or if no resources are available, the V-NSP 145-2 will return
a call req nack and the V-IBS 130-3 will release the call. The
V-IBS 130-3 sends a Q.931 call proceeding message to the V-LDS
140-1 after successfully paging the MS. This connects the B-channel
to the V-LDS 140-1.
[0123] In step "e," the V-IBS 130-3 sends a DTC designation message
to the MS and verifies the MS is on the DTC by monitoring the
returning DVCC code status change. After the MS locks onto the DTC
(DVCC code status change), the V-IBS 130-3 sends an IS-136 alert
with info message to the MS to indicate ringing to the user. The
V-IBS 130-3 also sends a Q.931 alert message to the V-LDS 140-1.
The V-LDS 140-1 sends an ISUP address complete message (ACM) to the
H-LDS 140-2 and the H-LDS 140-2 sends an ISUP ACM message to the
PSTN 100 to complete the end-to-end connection. The V-LDS 140-1
generates alerting (ringback tone) to the originating user.
[0124] In step "f," when the DN-based visiting subscriber picks up
the call, the MS sends an IS-136 connect message to the V-IBS
130-3. The V-IBS 130-3 sends a Q.931 connect message to the V-LDS
140-1. The V-LDS 140-1 sends an ISUP address answer message (ANM)
to the H-LDS 140-2 and the H-LDS 140-2 sends an ISUP ANM message to
the PSTN switch. The PSTN switch connects the caller and thus the
new VNZ voice path is established.
[0125] Call Delivery to a DN-based Subscriber, the DN being a
Ported Number from ILEC
[0126] FIG. 5d describes the signaling flow scenario of a PSTN
caller dialing the DN-based LCS subscriber when the called MS's DN
is a ported number from ILEC. As already described, LCS subscribers
may carry their existing residential landline phone numbers to the
subscribed HNZ for LCS services. The MS is registered with the
H-IBS 130-2 in the HNZ 105-1. In step "a," the originating PSTN
switch receives a call with a ported DN; so the PSTN switch sends a
TCAP LRN REQUEST message to the STP for a 6-digit LRN Global Title
Translation (GTT) for call routing information. The STP performs
GTT on the DN to determine the point code of the appropriate SCP
database and sends a TCAP LRN routing instruction request to the
SCP. The SCP's LRN application does 10-digit translation to
determine the LRN of the terminating office and sends an LRN reply
message to the originating PSTN switch based on the originating
point code in the incoming message. The STP forwards the LRN reply
to the PSTN switch without changing any protocol elements.
[0127] In step "b," the originating PSTN switch receives the LRN
reply message, processes the message and uses the information for
call routing. The PSTN switch sends an ISUP LAM message to the HNZ
LCS local switch (H-LDS) 140-2 based on the LRN reply. The H-LDS
140-2 sends a Q.931 call setup message to the H-IBS 130-2 based on
DN.
[0128] In step "c" the H-IBS 130-2 sends a CALL REQUEST message to
the H-NSP 145-1 to validate the call request. The H-NSP 145-1 may
initiate an authentication procedure with AC 190 when necessary.
The H-NSP 145-1 validates the call request by searching the ID
146-1 and discovers that the MS is currently registered in its
H-IBS 130-2. If the request is valid and resources are available,
H-NSP 145-1 will reserve the DTC and the B-channel. H-NSP 145-1
then sends a call request ack message with the resource information
to the H-IBS 130-2. H-IBS 130-2 starts to page the DN-based MS. If
the call request is not valid or no resources are available, the
H-NSP 145-1 will return a call request nack and the H-IBS 130-2
will reject the call. The IS-136 MS paging process has already been
described above.
[0129] In step "d," the H-IBS 130-2 sends a Q.931 call proceeding
message to the H-LDS 140-2 after successfully paging the MS. This
connects the B-channel to the H-LDS 140-2. The H-IBS 130-2 sends a
DTC designation message to the MS and verifies the MS is on the DTC
by monitoring the returning DVCC code status change. After the MS
locks onto the DTC (DVCC status change), the H-IBS 130-2 sends an
IS-136 alert with info message to the MS to indicate ringing to the
user. H-IBS 130-2 also sends a Q.931 alert message to the H-LDS
140-2. The H-LDS 140-2 sends an ISUP address complete message (ACM)
to the originating PSTN switch to complete the end-to-end
connection.
[0130] In step "e," the H-LDS 140-2 generates the alerting (ring
back tone) to the originating user. When the DN-based MS user picks
up the call, the MS sends a IS-136 connect message to the H-IBS
130-2. The H-IBS 130-2 sends a Q.931 connect message to the H-LDS
140-2. The H-LDS 140-2 sends an ISUP address answer message (ANM)
to the PSTN switch, the PSTN switch connects the caller and thus
the voice path is established, completing the call delivery
process.
[0131] The MS with a DN carried from a local exchange carrier (LEC)
may be registered in the VNZ, for example, VNZ 115-2. Referring to
FIG. 5e, step "a," the originating PSTN switch receives a call with
a ported DN and the PSTN switch sends a TCAP LRN REQUEST message to
the STP for a 6-digit LRN Global Title Translation (GTT) for call
routing information. The STP performs GTT on the DN to determine
the point code of the appropriate SCP database and sends a TCAP LRN
routing instruction request to the SCP. The SCP's LRN application
does a 10-digit translation to determine the LRN of the terminating
office, sends a LRN reply message to the PSTN switch based on the
originating point code in the incoming message. The STP forwards
the LRN reply to PSTN switch without changing any protocol
elements.
[0132] In step "b," the originating PSTN switch receives the LRN
reply message, processes the message and uses the information for
call routing. The PSTN switch sends an ISUP IAM message to the HNZ
LCS local switch (H-LDS) 140-2 based on LRN reply. The H-LDS 140-2
sends a Q.931 setup message to the H-IBS 130-2 based on the DN. The
H-IBS 130-2 sends a CALL REQUEST message to the H-NSP 145-1 to
validate the call.
[0133] In step "c," the H-NSP 145-1 validates the call by searching
the ID 146-1, and discovers that the MS is registered in a
subscribed VNZ (V-NSP) 115-2. It sends an IS-41-like ROUTREQ
message in IP format to the V-NSP 145-2 for routing instructions to
the DN-based MS. The V-NSP 145-2 verifies via the ID 146-2 that the
MS is still registered and is idle in V-IBS 130-3. It reserves an
available FDN from V-IBS 130-3, and returns a route request
response message including FDN to the H-NSP 145-1. The V-NSP 145-2
also reserves a B-channel for the FDN. If no FDNs are available,
the V-NSP 145-2 rejects the call which ultimately results in
rejecting the call to the originating user.
[0134] In step "d" the H-NSP 145-1 sends a call req ack message to
the H-IBS 130-2 with an indication to forward the call to the FDN
from the V-NSP 145-2. The H-IBS 130-2 sends a Q.932 facility
message to the H-LDS 140-2 to reroute the call to the DN-based MS
using FDN. The H-LDS 140-2 sends the facility return result in a
disconnect message for response to the facility invoke message to
the H-IBS 130-2; on receipt of the disconnect message, the H-IBS
130-2 sends a release message to the H-LDS 140-2, and H-LDS 140-2
sends a release complete message in return. Immediately after
sending the disconnect message, the H-LDS 140-2 sends an ISUP LAM
message to the V-LDS 140-1 based on the FDN.
[0135] In step "e," the V-LDS 140-1 now has the call. V-LDS 140-1
sends a Q.931 setup message to the V-IBS 130-3 based on the FDN.
The V-IBS 130-3 sends a call request message to the V-NSP 145-2 to
validate the call. As before, the VH-NSP 145-2 may initiate
authentication procedures via an authentication center when and if
necessary. The V-NSP 145-2 uses the ID database 146-2 to locate the
record of FDN-to-DN mapping to validate the call. If the request is
valid and resources are available, V-NSP 145-2 will reserve the DTC
and the B-channel (reserved when the FDN was assigned to the call).
V-NSP 145-2 then sends a call request ack message with the resource
information to the V-IBS 130-3. V-IBS 130-3 starts to page the
DN-based MS. If the call request is not valid or no resources are
available, the V-NSP 145-2 will return a call request nack and the
V-IBS 130-3 will reject the call. Briefly, the IS-136 MS paging
process is as follows: the V-IBS 130-3 broadcasts an IS-136 page
for the DN-based MS. The MS must respond with an IS-136 page
response within a specified time period. If the MS does not
respond, the V-IBS 130-3 will release the call. The V-IBS 130-3
sends a Q.931 call proceeding message to the V-LDS 140-1 after
successfully paging the MS. This connects the B-channel to the
V-LDS 140-1.
[0136] In step "f" the V-IBS 130-3 sends a DTC designation message
to the MS and verifies the MS is on the DTC by monitoring the
returning DVCC code status change. After the MS locks onto the DTC
(DVCC status change), the V-IBS 130-3 sends an IS-136 alert with
info message to the MS to indicate ringing to the user. It also
sends a Q.931 alert message to the V-LDS. The V-LDS 140-1 sends an
ISUP address complete message (ACM) to the H-LDS 140-2, and the
H-LDS 140-2 sends an ISUP ACM message to the PSTN 100 originating
switch to complete the end-to-end connection. The V-LDS 140-1
generates the alerting (ring back tone) to the originating
user.
[0137] In step "g," when the DN-based visiting subscriber picks up
the call, the MS sends an IS-136 connect message to the V-IBS
130-3. The V-IBS 130-3 sends a Q.931 connect message to the V-LDS
140-1. The V-LDS 140-1 sends an ISUP address answer message (ANM)
to the H-LDS 140-2. The H-LDS 140-2 sends an ISUP ANM message to
the PSTN switch. The PSTN switch connects the caller and thus the
new voice path is established.
[0138] Advanced Intelligent Network triggers may also be used for
call delivery for DN based MS. The LCS subscriber's DN is
provisioned for the AIN Termination Attempt Trigger (TAT) in the
serving LDS. When a call is delivered to the LDS for the
subscriber's DN, the TAT is encountered and the LDS sends a call
treatment query message to the NSP. The NSP locates the mobile in
their serving IBS and reserves an FDN in this IBS. NSP then directs
the LDS 140 to deliver the call to the MS based on the FDN.
[0139] Referring to FIG. 5f, step a, a PSTN user dials a LCS
subscriber's DN. The LDS 140 receives the ISUP IAM message from
PSTN. The incoming call to a TAT provisioned DN directs the LDS 140
to request for routing instructions from H-NSP. H-NSP finds that
the subscriber's MS is active in an IBS, and pages the MS 10.
[0140] In step b, after the MS 10 responds to the page, H-NSP
directs LDS to forward the call to the FDN of the serving IBS.
[0141] In step c, LDS 140 sends Q.931 Setup message to the IBS. IBS
sends Digital Traffic Channel (DTC) Designation message to MS 10
and sends Q.931 Call Proceeding message to the LDS. MS tunes to the
traffic channel. IBS then detects the MS is on the traffic channel
via DVCC status change. IBS 130 alerts the MS 10 and the MS 10
acknowledges.
[0142] In step d, IBS 130 sends ISDN Alerting message to LDS. When
the MS answers, IBS sends ISDN Connect message to LDS. LDS then
sends ISUP ANM message to PSTN switch and cuts through the voice
path.
[0143] The Intra-Cell Mobile Assisted HandOff (MAHO)
[0144] There are two hand-offs possible in LCS service: an
intra-cell mobile assisted hand-off (MAHO) and an inter-cell
hand-off(for example, from an HNZ 105-1 to a VNZ 115-1 via a buffer
zone). This section describes the end-to-end signaling flow
scenario of Mobile Assisted HandOff (MAHO) between different RF
channels within an IBS such as IBS 130-2 or cell such as home
neighborhood zone (HNZ) 105-1.
[0145] In this invention, the preferred method is to use the radio
frequency self-configuration algorithms as described above, which
may be implemented in the LCS network system to utilize the
available RF channels that are not used by the primary
macro-cellular system (represented by WS cell 101-2 in FIG. 1) for
intra-cell hand-off. However, such a radio frequency
self-configuration is an option and not mandatory for this
invention.
[0146] When the LCS system does use a radio frequency self
configuration algorithm, whenever the primary system starts to use
the same RF channel, the radio in the LCS system and the active
user may be required to move to another RF channel through the
assistance of the RF self-configuration subsystem. As already
described, each zone in a LCS system preferably has only one IBS
130. Once a RF channel is determined as noisy (e.g., from data
received signal strength, RSSI, and/or the bit error rate), all the
TDMA time slots within the channel may be considered to be noisy.
In the intra-cell handoff scenario, therefore, all the active
mobile stations using the noisy channel would re-tune to a new
frequency.
[0147] Intra-cell handoff is attempted when the BER is high (bad)
and the RSSI is good. (The threshold values for the BER and the
RSSI may be provided by the RF Self-configuration subsystem). Upon
receiving the request from the IBS 130 when handoff is needed, the
RF Self-configuration subsystem may perform a calculation and
return a new carrier frequency to the IBS 130 and the active MSs to
re-tune to, or it may return a reject message when no carrier is
available. If a new channel is available, the IBS 130 must re-tune
to that new channel before the MS 10 does.
[0148] When no new channel is available for the intra-cell handoff
(i.e., the intra-cell handoff attempt has failed) but the RSSI from
a neighboring IBS 130 is acceptable, the LCS system may attempt to
handoff the active MSs to the neighboring IBS (V-IBS) 130 through
intra-NSP handoff procedures (described in the next section).
[0149] If no channel is available for the handoff and the RSSI and
BER measurement results of the current channel reach threshold
values, the call may be dropped. The MS 10 may be capable of
performing the IS-136 channel measurement (RSSI and BER)
procedures. Units of RF measurement used by the MS 10 can be
normalized by the IBS 130 if they are not consistent with IBS RF
measurement units. DTX Control is disabled (Discontinuous
Transmission not supported). The IS-136 Channel Quality messages
are sent over the SACCH.
[0150] The carrier channels may always be turned on even when the
channel is not currently used by any MS. Therefore, it is possible
for the MS 10 to perform channel measurement on these channels. No
reconfiguration of the ISDN connection as a result of the
intra-cell handoff is necessary.
[0151] Referring to FIG. 6a, step "a," an active call between the
MS 10 and the PSTN user (or another MS user) involving an LDS (for
example, LDS 140-2) and an IBS, such as IBS 130-2 is in progress
using air interface channel A.
[0152] In step "b," the RF Self-configuration subsystem in the IBS
130-2 performs an RF Self-configuration algorithm and exchanges
information with other IBSs (in the present example, IBS 130-1) in
the subscribed-to zones.
[0153] In step "c," based on the information collected by the
algorithm, the RF Self-configuration the subsystem determines which
RF channels have to be measured by the MS. The IBS 130-2 sends the
Measurement order (over the FACCH) to the registered MS 10. The MS
10 acknowledges the instruction by sending the Measurement order
ACK message back to the IBS 130-2 (over the FACCH). The MS 10
follows the MAHO procedures defined in the IS-136.2 specification
and sends channel quality message to the IBS 130 (over the SACCH)
in response to the Measurement order message.
[0154] In step "d," when the IBS 130-2 detects an intra-cell
handoff condition based on the received channel quality message
(i.e., BER and RSSI), the IBS 130-2 sends an intra-cell handoff
request for a new channel to the RF Self-configuration subsystem.
The subsystem performs a calculation and/or sends a new carrier
frequency information to the IBS 130-2. Upon receiving the
information, the IBS 130-2 sends a handoff command, in accordance
with the IS-136.2 specification, to the MS (over the FACCH)
requesting the MS to re-tune to a new RF channel (along with other
channel assignment information). Handoff ACK is sent by the MS
(over the FACCH). Responsive to receiving the acknowledgment from
the MS, the IBS 130-2 re-tunes to the new RF (channel B).
[0155] In step "e," the MS turns off its transmitter, adjusts its
power level, tunes to a new RF channel b, sets stored DVCC to the
DVCC information element of the handoff message, sets the transmit
and receive rate to that indicated by the Rate information element,
and sets the time slot to that indicated by the Timeslot Indicator
information element. Once synchronized, the MS turns on its
transmitter. The IBS 130-2 then detects that the MS 10 is on the
new channel via DVCC status change. Upon detecting the MS 10 on new
channel, the IBS 130-2 sends Handoff Result messages to the NSP
145-1. The handoff is completed, and the call continues.
[0156] An Intra-NSP inter-cell MAHO (HNZ to contiguous VNZ or VNZ
to contiguous VNZ))
[0157] When an active call is in progress, the MS measures the
neighboring setup channels and the current active channel for RSSI
and BER among other things. These IS-136 Channel Quality
measurements help the system determine if the MAHO procedure is
necessary to preserve the call. Furthermore, in order to perform a
smooth, lossless handoff between the IBSs, LCS uses the Directed
Call Pickup (DPU) with Barge-in feature of the LDS 140. DPU
establishes a three-way call without disturbing the current
call.
[0158] Referring to FIG. 6b, step "a," a mobile station is on an
active call. H-IBS 130-2 directs the MS to start measuring the
channel quality of the neighboring control channels and the current
channel. The MS acknowledges the order and starts sending the
IS-136 Channel Quality messages.
[0159] In step b, when H-IBS 130-2 detects a handoff condition
based on the received channel quality messages (a low threshold
value is reached), the H-IBS 130-2 sends a handoff request message.
This message includes a priority list of the neighboring IBSs
(V-IBS) such as V-IBS 130-1 along with the serving mobile MSID to
the H-NSP 145-1. H-IBS 130-2 also starts the handoff request timer
(T1). Once the H-NSP 145-1 receives the handoff request message,
the H-NSP 145-1 will start at the top of the neighboring IBS
(V-IBS) list and check the radio channel and B-channel availability
of each entry. When an available neighboring IBS (V-IBS), such as
V-IBS 130-1 is found, H-NSP 130-2 will request the V-IBS 130-1 to
prepare for a handoff for the MS (MSID) and starts timer T2. In
response, the V-IBS 130-1 will reserve the B-channel and the RF
resources and start to initiate a three-way call using the directed
call pickup with barge-in. IBS.sub.n sends a Q.931 Setup message
that includes a feature activation code for DPU and the DN for the
IBS 130 to barge-in upon, IBS.sub.O. IBS.sub.n 130-1 then waits for
the LDS to indicate that the call has connected to IBS.sub.O 130-2.
IBS.sub.n 130-1 then sends a Handoff Directive to IBS.sub.o 130-2
to inform the IBS that IBS.sub.n 130-1 has sucessfully established
a three-way call (DPU).
[0160] In step c, after receiving the Handoff Directive, IBS.sub.o
130-2 cancels timer T1. IBS.sub.o sends an IS-136 Handoff order to
the MS requesting it to retune to the new RF channel on IBS.sub.n
130-1. After the MS acknowledges the order, IBS.sub.o 130-2 starts
to release the ISDN B-channel and simultaneously informs H-NSP145-1
that it has completed the handoff to the new IBS, IBS.sub.n 130-1.
H-NSP 145-1 acknowledges this notification.
[0161] In step d, when the MS arrives on the new channel, detected
by IBS.sub.n 130-1 by the DVCC status change, IBS.sub.n 130-1 sends
a Handoff Result message to H-NSP 145-1. H-NSP 145-1 notes that the
handoff is completed to the new IBS and cancels timer T2. Voice
path is established via a new route and the call continues.
[0162] Call Processing for an LCS Subscriber Who Makes an Outgoing
Call
[0163] This section describes the signaling flow scenario for a
call originated by the LCS subscriber from a subscribed-to
neighborhood zone.
[0164] Referring to FIG. 7, step "a," the subscriber, for example,
subscriber 10 in HNZ 105-1 dials a number on the MS; the MS sends
an IS-136 origination message to the serving IBS 130-2. The IBS
130-2 sends a call request message to the NSP 145-1 to validate the
call. The NSP 145-1 may initiate an authentication procedure via AC
190 when necessary. The NSP 145-1 validates the MS via its
associated Intelligent Database (ID) 146-1. If the resources are
available, it reserves a B-channel and DTC, and sends a call req
ack message to the IBS 130-2 with the resource information. If no
resources are available, NSP 145-1 send a call req nack and the IBS
130-2 rejects the call.
[0165] In step "b," the IBS 130-2 sends a Q.931 call setup message
to the LCS local switch LDS 140-2. The LDS 140-2 sends an ISUP LAM
message to the destination switch in the PSTN 100 to initiate
end-to-end connection. The LDS 140-2 sends a Q.931 call proceeding
message to the IBS 130-2 to connect the B-channel to the LDS
140-2.
[0166] In step "c," the IBS 130-2 sends an IS-136 DTC designation
message to the MS and verifies the MS is on the DTC by monitoring
the returning DVCC code status change. The LDS 140-2 receives an
ISUP ACM message from the PSTN switch 100 and sends a Q.931 alert
message to the IBS 130-2. The ring back tone is established between
the LDS 140-2 and the MS.
[0167] Finally, in step "d," the LDS 140-2 receives an ISUP ANM
message from the PSTN switch 100 when the destination user finally
answers. The LDS 140-2 sends a Q.931 connect message to the IBS
130-2 to complete the end-to-end connection. The IBS 130-2 sends an
IS-136 connect message to the MS and the voice path is established,
thus completing the outgoing call process.
[0168] Thus, there has been described a complete system for
providing a new local cordless services where a mobile subscriber
may receive and make free calls within their subscribed-to
neighborhood zones.
[0169] All United States patents referred to herein should be
deemed to be incorporated by reference as to their entire contents.
The following copending patent applications, which have each been
filed on the same day as the present application (the first one
listed below being the present application), are hereby
incorporated by reference as to their entire contents:
[0170] U.S. patent application Ser. No. TBD (Attorney Docket No.
03493.75951; Client Reference No. Chow 4-41-40-10-2), entitled
"Neighborhood Residential Cordless Services," invented by A. Chow
et al.
[0171] U.S. patent application Ser. No. TBD (Attorney Docket No.
03493.76142; Client Reference No. Chow 340-39-9-1), entitled
"Automatic Status Indicators for Neighborhood Cordless Services,"
invented by A. Chow et al.
[0172] U.S. patent application Ser. No. TBD (Attorney Docket No.
03493.77803; Client Reference No. Chow 10-1-7), entitled "Using
Over-the-Air Activation Tele-Service (OATS) . . . ," invented by
Chow et al.
[0173] U.S. patent application Ser. No. TBD (Attorney Docket No.
03493.77824; Client Reference No. Chow 12-8-10), entitled
"Automatic Service Selection Feature," invented by Chow et al.
[0174] U.S. patent application Ser. No. TBD (Attorney Docket No.
03493.77825; Client Reference No. Chow 11-41-2-8), entitled "Method
for Billing Subscribers With Neighborhood Cordless Residential
Service," invented by Chow et al.
[0175] U.S. patent application Ser. No. TBD (Attorney Docket No.
03493.77826; Client Reference No. Chow 6-1-3-3), entitled
"Neighborhood Residential Cordless Service Call Handoff With Call
Barging," invented by Chow et al.
* * * * *