WO1997024004A1

WO1997024004A1 - Integrated cellular and wireline telephone service

Info

Publication number: WO1997024004A1
Application number: PCT/US1996/019879
Authority: WO
Inventors: Steven Robert Donovan
Original assignee: Mci Communications Corporation
Priority date: 1995-12-22
Filing date: 1996-12-17
Publication date: 1997-07-03

Abstract

An integrated cellular and wired lined telephone system includes a mobile cellular network (12) coupled to a public switched telephone network (18).

Description

INTEGRATED CELLULAR AND WIRELINE TELEPHONE SERVICE

BACKGROUND OF THE INVENTION

Field of the Invention

This invention relates to communication systems.

More particularly, the invention relates to systems and methods for

integrated portable cellular and wired line telephone service.

Background Discussion

Mobile cellular and personal communication system (PCS) devices

allow users to place or receive telephone calls at any point throughout

a wireless telephone network. A cellular/PCS device is convenient when

the user is mobile, since it accesses a telephone network using a wireless

link. However, a call made or received on a cellular/PCS device is much

more expensive than a call on a wired line network due, in part at least,

to the high costs required for installing, operating and maintaining an air

link for the cellular/PCS device. To lower the costs of cellular/PCS

service, one industry proposal is to have a subscriber personal base

station, for example, a cordless phone receiver, originate a call to a cellular/PCS network, notifying the network to route all cellular calls to

a subscriber's wired line phone number when the subscriber's

cellular/PCS device is within range of or docked in the base station. The

originated call from the base station goes to a new network element at

a mobile switching center that answers the call, collects the necessary

information, emulates a visitors location register (VLR) and originates

a registration notification to a subscribers home location register (HLR).

When registered, the call will result in the HLR querying the new

network element or special VLR for re-routing information on all

subsequent calls made to the subscriber's cellular number. The special

VLR will respond to the HLR by re-routing such subsequent calls to the

subscribers wired line phone number. However, such special VLRs

result in higher network costs for equipment and maintenance and

further result in more signalling overhead for cellular/PCS networks.

Accordingly, there is a need to further improve integrated cellular and

wired lined telephone service to eliminate special equipment and

accompanying additional signalling thereby enabling subscribers to effect

savings in the costs of air time for calls made to a subscriber's

cellular/PCS device number while the subscriber is at home. SUMMARY OF THE INVENTION

The present invention satisfies the need previously described in a

cellular/PCS network. The invention includes a Mobile Switching Center

(MSC) coupled to a public switched telephone network (PSTN). Each

cellular/PCS device in the network cooperates with a personal base

station at the subscriber location. The personal base station has the

facility to detect the presence of the cellular/PCS device within a selected

range. When a cellular/PCS device is within the selected range of or

docked in the personal base station a message is sent by the base station

over an airlink to the MSC and on to the HLR. The message causes the

MSC under the direction of the HLR to forward the subscriber's

incoming cellular call to his plain old telephone service (POTS)/wired

line service instead of to his cellular device thereby saving airtime. A

home location register (HLR) in the PSTN serving the mobile switching

center for the cellular/PCS device is modified to have a new type of call

forwarding protocol. The new call forwarding protocol is activated only

when the subscriber⁵ cellular/PCS device is within range of or docked in

the personal base station. In this case, all calls to the cellular/PCS device

are routed to the subscriber's wired lined phone number. Several alternate methods are provided for notifying the HLR of the need to

activate the new "subscriber home" call forwarding method. A first

method involves the personal base station originating a signalling

message to the HLR indicating that the subscriber's cellular/PCS device

is at the home location. A second method involves the subscriber's

cellular/PCS device originating a signalling message to the HLR

indicating that it is within range of the personal base station and thus

home.

In the foregoing methods, the "subscriber home" call forwarding

for his wired line phone would be deactivated upon a receipt of a

registration notification from the subscriber's cellular/PCS device.

BRIEF DESCRIPTION OF THE DRAWING

The invention will be better understood from the following

description of preferred embodiments taken in conjunction with the

accompanying drawing, in which:

Figure 1 is a block diagram of an integrated cellular and wired line

telephone system incorporating the principles of the present invention. Figure 2 is a flow diagram of a cellular registration in the cellular

network of Figure 1.

Figure 3 is a flow diagram of a personal base station registration

in the cellular network of Figure 1.

Figure 4 is a flow diagram of a cellular call termination in the

cellular network of Figure 1.

Figure 5 is a flow diagram of a personal base station call

termination in the cellular network of Figure 1.

Figure 6 is a flow diagram of a personal base station de-

registration in the cellular network of Figure 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In Figure 1, a conventional cellular/PCS device 10 which is part of

a mobile cellular network including a plurality of devices 10 (not shown) is coupled to a mobile switching center (MSC) 12. The mobile device

10 is operated by a subscriber having a home location or office which

includes a personal base station 14 coupled over an airlink to the MSC

and a standard wiredline telephone 16 coupled through a wire line 20

and an end office 22 to a public switched telephone network (PSTN) 18.

The end office is a typical end office providing user with wiredline plain

old telephone service (POTS) to the telephone 16. Also coupled to the

network 18 is any calling phone 24 which may be wireless or wired line,

able to originate a phone call to a cellular/PCS subscriber.

The personal base station 14 detects the presence of the

cellular/PCS device 10 when within a selected range or docked in the

base station 14. The base station 14 includes a conventional proximity

device and an interface to communicate over an airlink to the MSC to

which the cellular/PCS device is assigned. Any message originated by the

base station includes a source address of the base station and a

destination address of a home location register (HLR) 26. The base

station triggers a message to initiate call forwarding of the subscribers

incoming mobile calls to his POTS wired line service when the subscriber cellular/PCS device is within range of or docked in the base station. T e

base station also includes a message to the HLR assigned to the

cellular/PCS device to turn off call forwarding of cellular calls when the

device is not within the range of or docked in the base station. Also

included in the base station is a light or signal (not shown) to indicate

that call forwarding is or is not re-directing calls from the cellular/PCS

device to the POTS phone. The base station may also include an on/off

switch (not shown) to override the proximity detection device.

The MSC 12 includes a visitor location register (VLR). Both the

MSC and the VLR are typical components used in a cellular/PCS mobile

network. To this effect, the VLR includes a program stored in a memory

(not shown) to recognize messages sent by each base station indicating

whether call forwarding should be activated or deactivated for the

cellular/PCS device assigned to such base station. In response to such

message, the VLR identifies the address or phone number for directing

calls to the cellular/PCS device or to the POTS phone, as the case may

be. _*,_»._ΛaΛ 97/24004

A home location register (HLR) 26 coupled to the MSC VLR

manages the correlation between the phone 10 and the base station 14

in initiating or terminating the transfer of a mobile call between the

phone 10 and the phone 16. The HLR records in a data base (not

shown) the address or phone number to which calls should be directed

to for a subscriber's cellular/PCS device or his POTS phone, according

to the message received from the VLR.

Turning to Figure 2, a typical cellular phone registration with the

MSC is shown. This call flow would be used for all registration by the

subscriber's cellular/PCS device. In an operation 201, a subscriber

initiates the ceilular/PCS device registration with the HLR. The

procedure can be initiated when the subscriber powers on the phone;

originates a call; changes the MSC/VLR serving location as well as other

actions. In an operation 203, the cellular/PCS device sends a message

to the MSC/VLR serving the phone. In an operation 205, the

MSC/VLR sends a message to the HLR indicating the location of the

cellular/PCS device and the call forwarding number serving the phone. The phone number for the cellular/PCS device is the default condition.

In an operation 207, the HLR records the location and the call

forwarding number of the cellular/PCS device in the HLR database.

Turning to Figure 3, the personal base station registration process

is shown. This registration procedure results from the subscriber^'s phone

being within range of or docked in the base station 14. In an operation

301, the base station 14 detects the cellular/PCS devices's radio signal or

the presence of the device docked in the personal base station.

In an operation 303, the personal base station initiates the

registration procedure after the detection of the presence of the

cellular/PCS device. In response to such actions, the base station out

pulses a message to the VLR containing a source address for the base

station; a destination address for the HLR assigned to the base station

and an identification number for call forwarding subscriber cellular call

to a POTS phone. In an operation 305, the MSC/VLR notifies the HLR of the

cellular/PCS registration and the call forwarding number. In operation

307, the HLR recognizes the change in registration and transfers any call

to the cellular/PCS device to the subscriber's wired line phone.

In Figure 4, a typical cellular call termination procedure is shown

for a cellular/PCS call. This call flow would be used when the subscriber

is not within the range of the personal base station.

In an operation 401, a call is originated from any phone to the

subscriber's cellular/PCS device number.

In an operation 403, the call traverses the necessary telephone

networks to the MSC/VLR associated with the subscriber's home MSC.

In an operation 405, the MSC/VLR queries the HLR for the

location and treatment for handling the call. In this instance the subscriber is being served by the same MSC that is the subscriber's home

MSC.

In an operation 407, the HLR indicates to the MSC that the call

is to be completed to the cellular/PCS device since the device is not

within the range of or docked in the base station.

In an operation 409, the MSC completes the call to the

cellular/PCS device.

In Figure 5, a basestation call termination process is shown when

the subscriber is within range of or docked in the personal base station.

In this case, the resulting call is forwarded to the subscriber's wired line

service and not to the cellular/PCS device. In an operation 501, a call

is originated from any phone to the subscribers cellular/PCS device

number. In an operation 503, the call traverses the necessary telephone

network to the MSC/VLR associated with the subscriber's home MSC

and initiates call processing.

In an operation 505, the MSC/VLR queries the HLR for call

handling information. In this instance, the HLR will have detected the

registration of the personal base station, as described in Figure 3. As a

result, the HLR will determine that the call is to be forwarded to the

subscriber's wired line service.

In an operation 507, the HLR indicates to the MSC that the call

is to be forwarded to the subscriber's local POTS phone.

In an operation 509, the MSC forwards the call to the end office

providing the subscriber local service. It should be noted that there will

not necessarily be direct trunking between the MSC and the end office. In an operation 511, the end office completes the call to the

subscriber's POTS phone.

In Figure 6, the call flow is shown for basestation deregistration

after a selected time interval when the subscriber's cellular/PCS device

is no longer in range of the personal base station. In this case, cellular

calls are directed to the subscriber^'s cellular/PCS device.

In an operation 601, the base station detects that the cellular/PCS

device is no longer within its range either by the loss of the radio signal

or the removal of the cellular/PCS device from the docking station.

In an operation 603, the base station after a selected time interval

initiates de-registration from the network, i.e., a simulated power down.

A message is sent by the base station through the MSC/VLR indicating

the de-registration condition of the base station.

In an operation 605, the MSC VLR forwards the de-registration

to the HLR. In an operation 607, the HLR updates the subscriber profile and

restore incoming calls to the cellular PCS device.

In summary, an integrated cellular and wired lined telephone

system has been described in which cellular calls are forwarded to a

wired lined phone at a subscriber location when a cellular/PCS device

assigned to such subscriber location, is within the range of, or docked in

a base station located at such subscriber location. When the cellular/PCS

device is not within the range of or docked in the base station, a second

message from the base station to the MSC causes the call forwarding

address stored in the HLR to forward calls to the cellular/PCS device.

The system lowers the use and cost of air time by a cellular/PCS device

which makes such service more attractive to the general public. Further,

the improvement is achieved with few modifications to a conventional

mobile cellular telephone system.

While the present invention has been described with respect to

specific embodiments, the description is illustrative of the invention and

is not to be construed as limiting the invention. Various modifications may occur to those skilled in the art without departing from the spirit and the scope of the invention.

Claims

CLAIMSWhat is claimed is:

1. An integrated cellular and wireline telephone system

comprising:

a) a mobile cellular network comprising a plurality of

cellular/personal communication system (PCS) devices;

b) a personal base station and a plain old telephone service

(POTS) phone served by a wired line installed at a subscriber location

to which a cellular/PCS device is assigned;

c) means for processing a call initiated by any telephone to

the cellular/PCS device;

d) means included in the personal base station for detecting

the presence of a radio field associated with the cellular/PCS device; and

e) means for notifying the processing means to forward all

calls to the POTS phone instead of the cellular/PCS device when the

cellular PCS device is within the radio range of or docked in the

personal base station.

2. The integrated cellular and wired line telephone system of

claim 1 wherein the personal base station initiates a message from the

base station to the system when the cellular/PCS device is not within the

range of or docked in the base station.

3. The integrated cellular and wired line telephone system of

claim 1 further comprising a home location register for providing the

phone number to direct calls to the cellular/PCS device when the cellular

PCS device is within the range of or docked in the personal base station.

4. The integrated cellular and wired line telephone system of

claim 3 further comprising means for initiating a message from the

personal base station using an air link to the means for processing calls,

the message including a message source address; a message destination

address and an address or phone number for the system to direct calls

to the cellular/PCS device.

5. The integrated cellular and wired lined telephone system of

claim 4 wherein the means for processing a call includes a visitor

location register for receiving messages from the personal base station

and notifying the home location register of the address or location to

direct calls for the cellular/PCS device assigned to the base station.

6. The integrated cellular and wired lined telephone system of

claim 5 wherein the VLR notifies the HLR the status of the cellular/PCS

device relative to the personal base station when the device is not within

the range of or docked in the base station.

7. In an integrated cellular and wired lined telephone system,

a method for transferring calls to a wired line phone when such call is

directed to a cellular/PCS device which is within the range of or docked

in a personal base station coupled to the system comprising the steps of:

a) initiating through the system a call from any telephone to

a cellular/PCS device;

b) detecting the presence of the cellular/PCS device when

within the range of or docked in the personal base station; c) initiating a message to the system including a mobile

switching center and public switched telephone network when the

cellular/PCS device is within the range of or docked in the personal base

station;

d) notifying a home location register included in the system

of a call forwarding number when a message is received by the system

from the base station; and

e) providing the call forwarding address to the system to re¬

direct the call to the cellular/PCS device to a wired lined phone located

at a subscriber location to which the cellular/PCS device is assigned.

8. The method of claim 7 further comprising the steps of

generating a second message from the personal base station to the

system when the cellular/PCS device is not within the range of or docked

in the personal base station; and

changing the call forwarding address in the home location register

to the phone number for the cellular/PCS device when the second

message is received by the home location register.

9. The method of claim 8 further comprising the step of

generating a message by the personal base station when the cellular PCS

device is not within the range of or docked in the base station.

10. The method of claim 9 further comprising the step of a

visitor location register (VLR) in the system querying the

HLR for location and call treatment handling a call directed to the

cellular/PCS device.