WO1999031905A1

WO1999031905A1 - Method and system for operating a radio communication network combining a wireless telephone with the telephone network

Info

Publication number: WO1999031905A1
Application number: PCT/FR1998/002749
Authority: WO
Inventors: Frédéric Heurtaux; Jean-Paul Thierry; Jean-Marc Dimech
Original assignee: Sagem S.A.
Priority date: 1997-12-16
Filing date: 1998-12-16
Publication date: 1999-06-24
Also published as: FR2772540B1; TW416256B; FR2772540A1; EP1040686A1; AU1764499A

Abstract

The invention concerns a method for setting up telephone communication by integrating a cellular telephone system (1) and a switched telephone network (2), when the user of a radio network mobile telephone (14) is capable of being in a volume of signals perceiving incoming calls transmitted by a fixed telephone (22) wired to the switched network (2). The method consists in forwarding in the networks, towards the fixed telephone (22), calls made to the mobile telephone (14) and disconnecting (142) the latter.

Description

METHOD AND SYSTEM FOR OPERATING A RADIO COMMUNICATION NETWORK ASSOCIATING A TELEPHONE WITHOUT FTL TO THE TELEPHONE NETWORK

A radiocommunication telephone of a cellular telephone network allows its user to establish communications during his travels but his battery has only a limited autonomy. It debits permanently, during a communication or even in standby since the phone then receives and recognizes location messages from the base station covering the radio cell in which it is located and to which it may have to respond if it changes cell.

The standby mode, intended to keep the main function of the telephone operational, which is to establish communications, does have a reduced instantaneous consumption but, as the standby represents the most frequent state, consumption in this mode weighs heavily on the balance sheet energy of the phone.

The present invention aims to limit the consumption of the telephone outside of communication periods.

To this end, the invention relates first of all to a method of establishing a telephone call by integrating a cellular radio network and a switched telephone network, method in which, when the user of a mobile telephone of the radio network is likely to be in a volume of perception of incoming call signals emitted by a fixed telephone connected by wire to the switched network, we order, in networks, a forwarding, to the fixed telephone, calls to the mobile phone and the power is cut off.

Naturally, the term “fixed telephone” is understood to mean a telephone which is generally fixed and therefore capable of being permanently supplied by wire, connected to the switched telephone network. Such a definition obviously does not exclude either a telephone comprising a base connected by wire to the telephone network and a handset of this mobile telephone, in non-wired connection with the base, or a fixed station having a radio link with the network. Thus, in practice, as soon as the carrier of the mobile telephone can hear the ringing or see a call indicator of the fixed telephone, it is the latter which receives the incoming calls. Outgoing calls will of course also be established preferably by the landline telephone, the carrier of the mobile telephone remaining however free to replenish it to establish a second outgoing call, or simply to order the removal of the forwarding and thus be able to be called on the mobile phone.

The invention is not related to the type of information passing through the networks, that is to say that it applies just as well to data communications as to voice communications.

Preferably, the referral is suppressed by re-establishing the power supply and detecting this re-establishment to send, to the radio network, a corresponding command.

This avoids any intervention by the wearer and any oversight on his part.

Advantageously, the telephone call number of the fixed telephone is specified in the return command.

Incoming calls can be forwarded to any terminal where the carrier is located.

Advantageously also, the presence of the mobile telephone is detected in the perception volume of the fixed telephone in order to automatically control the forwarding.

The return does not therefore require any intervention by the carrier.

The invention also relates to an integrated set of a switched telephone network and a cellular radiotelephone network comprising means for receiving call forwarding remote controls, intended for mobile telephones of the radio network, the reception means being arranged to control the forwarding of calls, through the switched telephone network, to a telephone connected by wire to it. The invention will be better understood with the aid of the following description of a preferred embodiment of the method of the invention by means of an integrated set of networks according to the invention, with reference to the attached drawing, on which :

FIG. 1 schematically represents the integrated set of networks and associated telephones, and

- Figure 2 illustrates the exchange of data in networks, for the management of referrals.

FIG. 1 very schematically represents an integrated communication network comprising a cellular radio network 1 and a switched telephone network 2, connected by a multiple link 3. Two base stations, 12, 13, of network 1, have been represented, connected to a switching part 10 of the network 1. To the telephone network 2 are connected fixed telephone sets like 21 and 22.

A mesh of switching nodes 17, 18, 19 of the switching part 10 of the network 1 has been shown diagrammatically, to which the stations 12, the link 3 and a link 15 respectively connecting the station 13 are connected.

Likewise, a mesh of three switching nodes 27, 28, 29 of the telephone network 2 has been shown, respectively connected to the telephone sets 21 and 22 and to the link 3.

A mobile phone like 14 can be called from any other mobile like 11 or landline phone 21, 22.

In the latter case, the call is routed via link 3, after analysis of the number called. However, when the user of the mobile telephone 14 of the radio network 1 is likely to be in a volume of perception of incoming call signals sent by a fixed telephone 22 connected by wire to the switched network 2, control is carried out in the networks, a forwarding, to the fixed telephone 22, of the calls intended for the mobile telephone 14 and the supply of the mobile telephone 14 is cut off.

In other words, when the wearer of the telephone 14 is for example in his office, which includes the landline telephone 22 which he can hear the ringtone, it diverts incoming calls to the mobile phone 14 to the telephone 22.

For this, the bearer of the telephone 14 sends a radio message to the network 1 to order a diversion or return to the telephone 22 of the calls from the switching part 10 normally intended for the station 13 (link 15). A call to telephone 14 is thus diverted on link 3 to prevent it from leaving on link 15.

In order to avoid a round trip by the link 3 in the event of a call coming from the telephone set 21, it can be provided that the telephone network 2 can consult the state of call forwarding tables of network 1, for example by a signaling network of a signaling network using for example the CCITT No. 7 or LAP protocol.

It will be recalled that a network of signaling signaling channels functionally constitutes a system for managing a network of switched communication channels. Physically, these are time channels reserved in time frames carrying communications. The signaling channels allow any central unit of a telephone exchange, or node, to interrogate another exchange on the busy or dismissal status of a called subscriber attached to it. This makes it possible to immediately return a busy signal, if necessary, without having to unnecessarily reserve a path of communication circuits to the called subscriber or, as here, to choose from the outset an optimal path to extension 22 corresponding to the forwarding number.

The forwarding can be a simple forwarding order, the call number of the forwarding station 22 having been initially declared as such to the radio network 1. It can be provided to be able to modify the forwarding number, by specifying it in the command of dismissal.

In particular, the mobile telephone 14 includes a button 141 for cutting off its power supply 142, button 141 managed by a microprocessor 140. The microprocessor 140 detects the activation of the button 141 and presents a message on a display 143, to request a forwarding number and, after entering it, using a keyboard 144, the microprocessor 140 sends the corresponding forwarding command from the radio network 1, and executes the power cut command 142. As explained above, the radio network forwarding command 1 can be a diversion in network 1 of a radio call (11) or a refusal to access (3) to network 1 from network 2 or even acceptance of such access (3) to a called node (19), followed by a referral at this level (19) to network 2 through link 3.

The removal of the forwarding occurs by restoring the power supply to the mobile phone 14, by further activation of the key 141, and this restoration is detected, in fact executed, by the microprocessor 140 which scans the key 141, in order to transmit, to the network radio 1, a corresponding command. Provision may be made for the transmission of the command to delete the forwarding to be delayed until an outgoing radio call is established, which avoids explicitly controlling the mobile telephone 14 by the key 141.

The operation of the integrated network 1, 2, 3 will be explained below.

On reception, through the link 15, of an order relating to a return from the telephone 14, the node 19 transmits this to a return manager, here central, assumed to be located in another node, here that referenced 17. The latter includes a forwarding table 171 providing correspondence between any radio subscriber and a possible forwarding number.

In the event of a call to the station 14 from the mobile telephone 11, the node 17 consults the table 171 according to the number dialed and divert the call to the link 3, in the presence of a forwarding number to a terminal (21, 22) of the telephone network 2. If the calling mobile telephone was connected to another node (18, 19), the latter node would consult, here by signaling channel, table 171.

Note, however, that it is possible to constitute partial deflection tables, distributed in the nodes 17, 18, 19, or even the stations 12, 13. The diversion may only occur at the level of the terminal part ( 19) of the communication circuit going from the calling party to the called party (13, 14). This risks not optimizing the length of this circuit, but avoids the remote consultation of a central file (171). However, provision may be made for the input node 17 to consult the reference table of the terminal node 19, as in the case of the central file 171. If the mobile telephone 14 is called from the fixed telephone 21, the principle set out above remains generally valid. Preferably, as already explained, the telephone network 2 (the node 27) consults by signaling channel table 171, or one of the partial tables, by link 3 and, in the absence of forwarding, establishes until telephone 14 a circuit or path passing here through elements 27, 3, 18, 19, 15, 13 or bypass elements, in the event of saturation.

In the event of forwarding, the forwarding number (extension 22) read in the forwarding table 171 is substituted, in node 27, for the number dialed by extension 21 and a circuit passing through the elements 27, 28 is established until fixed station 22 for reference.

It is understood that the reference table 171 could be located in the telephone network 2, while remaining accessible to the radio network 1.

Furthermore, the return of the mobile telephone 14 could, as a variant, be ordered by any fixed station 21, 22, by calling table 171, with supply of a call number identifying the station 14, of the return number, and, preferably a confidential protection key to certify that the order is valid.

FIG. 2 schematically illustrates, in more detail, the exchanges of signals managing the references, between the nodes 17, 19 and 27.

A return command from the telephone 14 is temporarily stored, with a global message containing it, in a register 191 of the node 19. It contains a return number (22), with which is associated the call number identifying the telephone 14 supplied by the station 13. A management circuit 192 selects the message field containing the command, extracts it and formats it for its transmission according to the desired protocol. The circuit 192 then addresses the node 17, more precisely the table 171, and issues the return command by managing the above exchange protocol.

In node 17, a receiving circuit 170, homologous to circuit 192, recognizes the command and adapts its presentation to address the address reserved for telephone 14 in table 171 and write the reference number (22) there.

The reference being declared to network 1, we will now explain in more detail its operation.

A call number (14) dialed by the station 21 is stored in a register 271 of the attachment node 27. Before using this call number, a central unit 270 of the latter reads the table 171, through node 29, link 3 and node 18. The exchange management circuits (cf. 192, 170), managing the exchange protocols, have not been shown here, for the sake of clarity.

The response from table 171 returns by the same route in a register 272 and in the central unit 270.

A two-channel multiplexer 273, controlled by the central unit 270, is connected to the respective outputs of the registers 271 and 272.

If the response from table 171 indicates an absence of referral, it is the register 271 which is read by the multiplexer 273; otherwise, the table 171 controls the forwarding of the call through the telephone network 2, because it is the forwarding number 22 contained in the register 272 which is read, by command of the microprocessor 270, and is substituted for the number dialed ( 14). In this example of a call from an extension (21) of the telephone network 2 and exploitation of signaling signaling optimizing the establishment of the paths in the networks 1, 2, the referral occurs from the start (27) in network 2, radio network 1 having established no initial path.

The “final” call number thus determined is used to address a network topography memory 274 2, determining the identity of the node (28) for attaching the station (22) having the reference number. The output of memory 274 commands a switching matrix to establish a time channel path to node 28 and station 22. The number called 22 is also transmitted, by signaling channel, to end node 28 in order to reach station 22 . It is understood that a call from a mobile telephone attached to any one of the nodes 17 to 19 is treated in the same way, each node of each network 1 and 2 comprising means (270, 271, 272, 273) table 171.

Provision may be made for the presence of the mobile telephone 14 in the call perception volume of the fixed telephone 22 to be detected, in order to automatically control forwarding, and to delete it in the absence of detection. This detection can take place, for example, by means of a current, or voltage, or magnetic field sensor, for example, of the mobile telephone 14, detecting that the latter is placed on a charging base, located a priori near the telephone 22. Provision may also be made for an access control system to detect the presence of the bearer of the telephone 14 and itself issue a forwarding command in the networks 1, 2, 3.

It can for example be a SIM card or access control badge which is used to control the return through a reader of this card. Such use is particularly advantageous when, for fear of the risk of explosion, mobile phones are confiscated at the entrance to risk areas.

Provision may also be made for the table 171, or the partial tables, to include, for each telephone 14, a default forwarding number which depends on the station (13) on which it temporarily depends, that is to say on the radio zone where it is located. Each telephone 14 therefore potentially has a plurality of forwarding numbers and, for example, if the mobile telephone 14 leaves the area of station 13 in favor of that of station 12, the forwarding number selected will be for example that of extension 21, supposed to be in the zone covered by station 12. A carrier of telephone 14 which would have two offices, in two different radio zones, could thus judiciously and automatically divert incoming radio calls to fixed station 21 or 22 from the respective office.

In particular, provision may be made for the mobile telephone 14 to have means for determining its geographical position or its environment and means for memorizing the positions of the volumes of perception of signals of incoming calls, that is to say of the position of fixed telephones and of the respective areas surrounding them.

As means of determining position, one can think of an integrated GPS receiver. It can also be the radio receiver of the phone

14 which includes field measurement circuits coming from several base stations such as 13. In this case, it is not guaranteed that the position of the telephone 14 is determined with precision, because obstacles can distort the relative levels of the received signals , but it is the radio environment of a determined place, comprising a fixed telephone, which will be memorized for later comparison with the environment then perceived, in order to order, if necessary, a referral to the fixed telephone. The absolute position can however be estimated from the instants of reception of frames coming from the various base stations, therefore by time triangulation, as with GPS.

The mobile telephone 14 may in particular include a calculation block, such as a Kalman filter, for estimating and improving stored models of its radio environment, by comparison between the signals received from the base stations. These models include a static reference model, corresponding for example to the case where the mobile telephone 14 is placed in an office. Variants of the reference model can be added, corresponding, for example, to the level modulation received when the office occupants are present, their movements being able to constitute an additional parameter of the models. If a model appears sufficiently similar to the detected environment, a return command is then sent.

We can also think, instead of a Kalman filter, to use a self-adaptive neural network, or Kohonen map, which, without necessarily establishing a model, will however establish correlations relating to the positions of the telephone 14 vis-à-vis vis its radio environment.

The mobile telephone 14 can thus recognize a plurality of fixed telephone zones and control a forwarding. A motion detector, possibly timed, integrated into the mobile telephone 14 can be provided to automatically control a cancellation of the forwarding when the mobile telephone 14 is entered by its user.

Claims

1.- Method for establishing a telephone call by integrating a cellular radio network (1) and a switched telephone network (2), method in which, when the user of a mobile telephone ( 14) of the radio network is likely to be in a volume of perception of arrival signals of calls emitted by a fixed telephone (22) connected by wire to the switched network (2), the user commands, in networks, a forwarding, to the fixed telephone (22), of the 0 calls intended for the mobile telephone (14) and it cuts the supply (142) thereof.

2.- Method according to claim 1, wherein the user removes the reference by restoration of the power supply (142) and the mobile telephone 5 (14) detects (140) this restoration to transmit, to the radio network (1) , a corresponding command.

3.- Method according to claim 2, wherein the transmission of the command is delayed in the mobile phone (14) until 0 the establishment of an outgoing radio call.

4.- Method according to one of claims 1 to 3, wherein the mobile telephone (14) specifies, in the return command, the telephone call number of the fixed telephone (22). 5

5.- Method according to claim 4, wherein the mobile telephone (14) detects a command to cut off its power supply (142) for, by means of man-machine relationship (140, 141, 143, 144), request a forwarding number and, after entering and sending the corresponding forwarding command 0, cut the power supply (142).

6.- Method according to one of claims 1 to 5, wherein the presence of the mobile telephone (14) is detected in the volume of perception of incoming call signals sent by the fixed telephone (22) to control automatically forwarding.

7.- The method of claim 6, wherein the detection of presence in the volume is carried out by comparing them with signals received from a plurality of respective base stations (12, 13) of the network.

8.- The method of claim 7, wherein the mobile phone (14) develops models of radio environment, it stores, then compare them to a detected environment and control, if necessary, the return.

9.- Method according to one of claims 1 to 8, wherein the movement of the mobile phone (14) is detected to cancel a forwarding.

10.- Method according to one of claims 1 to 9, in which the radio network (1) comprising a plurality of base stations (12, 13) for ensuring radio coverage of a corresponding plurality of zones, a number forwarding function of the base station in the area where the mobile phone (14) is located, is assigned to it.

I - Integrated assembly (1, 2, 3) of a switched telephone network (2) and of a cellular radio network (1) comprising means (171, 191, 192) for receiving call forwarding remote controls , intended for mobile telephones (14) of the radio network (1), the reception means being arranged to control the forwarding of calls, through the switched telephone network (2), on a telephone connected (22) by wire to that -this.

12.- The assembly of claim 11, wherein there is provided means (270, 271, 272, 273) for consulting a table (171) of reference numbers.

13.- The assembly of claim 12, wherein there is provided means for replacing (270, 273) a number called by a reference number read from the table (171).