WO2001069959A1

WO2001069959A1 - Mobile telephone system

Info

Publication number: WO2001069959A1
Application number: PCT/GB2000/004379
Authority: WO
Inventors: Nils Martensson
Original assignee: Ipr Industries Limited
Priority date: 2000-03-16
Filing date: 2000-11-17
Publication date: 2001-09-20
Also published as: GB0006370D0; AU1404501A

Abstract

A telephone system comprises cellular telephone means (mobile phone (10) and docking station (11), and a fixed telephone system (20-23, 31) coupled to a PSTN. Control (call interception means) are operative when the mobile cellular telephone is coupled to its docking station for detecting when a call is being initiated on the fixed telephone system and for diverting that call to the mobile telephone under the control of the mobile telephone system operator.

Description

Mobile Telephone System

Field of the Invention

The present invention relates to mobile telephone systems, and more specifically to techniques for enabling their usage to be increased.

Background of the Invention A mobile telephone is normally carried by its user, and when a call is made, it communicates via a cellular mobile system by radio. (There are many types and forms of mobile cellular radio system.) The user also has at least one charger or a docking station, from which the battery of the telephone can be charged. The charger or docking station is normally located at some place where the user spends considerable periods of time; a typical place is at their home.

Almost invariably, the user will also have a fixed telephone system at home or in an office, ie a telephone system connected to a PSTN (public switched telephone network). This connection will normally be through a land line (though radio relay links are occasionally used in special situations). The user's fixed telephone system will normally include one or more telephones, which may be ordinary wired telephones, cordless telephones, or both. The telephone system may also include other devices such as modems, fax machines, and answering machines.

The cost of making a call on a mobile telephone is generally considerably higher than the cost of a call on a landline. Users will therefore tend to use their mobile telephones only when they are away from home; at home, they will use the fixed telephone system connected to the landline.

Systems have been proposed, eg in EP 0 843 491 A2/A3 (Telecom Italia) and GB 2 311 91 1 A (Motorola), in which a mobile telephone is coupled to a fixed telephone system so that when the user makes a call, they can choose (either when making the call or in accordance with stored information) whether the call should use the PSTN or the mobile system.

Summary of the Invention

According to its main aspect, the present invention provides a telephone system comprising cellular telephone means, a fixed telephone system coupled to a PSTN, and call interception means operative when the cellular telephone means are operative for detecting when a call is being initiated on the fixed telephone system and for diverting that call to the cellular telephone means under the control of the cellular telephone system operator. ("Operator" means, of course, some sort of automatic system implementing the operation of the mobile telephone system operator, not the operator as a real person.)

Detailed description of Preferred Embodiments

Further features of the invention will become apparent from the following description of a telephone system embodying the invention and variations thereof.

Brief Description of the Drawings

The description is given by way of example and with reference to the drawings, in which:

Fig. 1 is a block diagram of the logical arrangement of the system, and Figs. 2 and 3 are block diagrams of two embodiments of the system.

Referring to Fig. 1, a mobile telephone 10 is shown docked in a docking station 11, which is powered off the mains (not shown) and provides charging current to charge the mobile unit 10. There is also a fixed telephone system comprising a wired telephone 31 , and a cordless telephone subsystem.

A cordless telephone consists of a base station and a handset which can be placed in the base station for charging but is removed from it if the user wants to take it with them around the house or when a call is made. (There may be more than one handset, and there may be further charging units for the extra handsets.) The handset is coupled to the base station through a short range coupling system, which is normally an induction coupling or radio system (though other couplings such as infra-red are possible in principle). Digital systems such as the system known as DECT are becoming increasingly popular for this purpose, and systems such as Bluetooth can also be used. In the present system, the cordless telephone subsystem comprises a base unit 20, a cordless handset 21 which engages with a socket 20A, a further cordless handset 22, and a further charging unit 23. The base unit 20 may include a further handset socket 20B if desired. Base unit 20 and charging unit 23 are powered off the mains (not shown). Handset 21 has been removed from its charging socket in the base station 20; handset 22 is in its charging unit 23.

The fixed telephone system would normally be connected directly to a telephone socket 41 which is connected to a landline 40, which typically forms part of a PSTN, and the mobile telephone 10 and its base unit 11 would be entirely separate from the fixed telephone system. In the present system, however, there are call interception means comprising a control unit 50 located between the main wiring 43 of the fixed telephone system and the socket 41 , and the docking station 1 1 of the mobile system is connected to the control unit 50.

The control unit 50 comprises a switch 50 which can couple the

PSTN line to either the fixed telephone system 20-23, 31 or the mobile telephone and docking station 10-1 1, a logic unit 52 which controls its operation, and a memory unit 53.

The control unit detects whether the mobile phone 10 is in its base unit 1 1. If the mobile phone is not in its base unit, or if an incoming call is received from the PSTN, the control unit operates switch 51 to connect the PSTN to the fixed telephone system. However, if the mobile telephone is in the docking unit and an outgoing call is made by the fixed telephone system, then the logic unit 52 may, in dependence on conditions discussed below, operate switch 51 to send the call to the mobile telephone docking station which passes it to the mobile telephone 10. The call can thus be routed through the mobile telephone instead of through the landline. The mobile telephone 10, with the docking unit 11, acts as a radio relay, which relays the communication path from the cordless telephone 21 or 22.

For this, the mobile telephone system (telephone 10 and docking unit or station 10) must be capable of indicating to the control unit 50 whether the mobile phone is in the docking station. The docking station 1 1 must also, of course, be provided with means for coupling the appropriate telephone signals (dialling signals and speech) to the mobile unit and (for speech signals) vice versa.

The control unit 50 was stated above to operate in accordance with certain conditions. These conditions may be determined by the control unit using the mobile phone 10 to communicate with the mobile telephone system (ie the base stations, etc); the mobile system determines whether or not it wants to accept the call being made, and signals back accordingly. Alternatively, the conditions may be determined or implemented by various criteria determined by the mobile telephone system stored in the memory unit 53; these criteria will specify the situations in which the mobile system (eg determined by time of day, stored tariff rates for the mobile system and the PSTN system, etc) will accept the call. Of course, both types of condition can be used in combination.

The call facility is thus provided by the mobile telephone system operator instead of the PSTN operator (which may be a public utility such as BT or a cable operator). The mobile telephone system operator will naturally charge a rate for this which is at least as low as the rate charged by the landline operator, and will normally be considerably lower than the rate normally charged for mobile telephone calls. A substantial usage of the present system is likely to be at off-peak times, when a working user is at home; the general loading of the mobile system is likely to be low at such times. The existing landline is used as a second choice in case the cellular telephone is not in its docking station (or docking range).

The fixed telephone system is shown as also including a fax machine 46 and an answering machine 47 connected on line 45. It will of course be realized that the fixed telephone system may contain further telephones and/or other units such as modems (not shown). Conversely, the fixed telephone system may contain only some of the units shown. It is also possible for further telephones to be attached to the line 42 between the socket 41 and the control unit 50, as shown at 30; calls from such telephones cannot be intercepted by the control unit 50, of course. The mobile system may of course filter its call interception, in various possible ways. The docking unit may include a clock unit which inhibits call interception at full-rate times, and/or a monitoring unit which inhibits interception of certain types of calls. The mobile system operator may analyse calls and refuse to accept certain calls, with the docking unit then passing these calls on to the landline. (The user will normally be unaware of this.) And, of course, if the mobile telephone system cannot accept a call, e.g. because it is busy or transmission conditions are unsatisfactory, the docking unit will pass the call on to the landline (again, the user will normally be unaware of this).

The system can of course be used for data signals, e.g. from computers and fax machines, as well as speech signals.

As soon as the mobile telephone is taken out of its docking unit, it reverts to its normal functioning. If desired, the docking unit may be provided with interlock means or an indicator to prevent a user from taking it out while an intercepted call is in progress or warn them against such removal.

When the docking station intercepts a call from the cordless telephone system, it is desirable for it to indicate to the mobile telephone system that this is a different call from one originated using the cellular telephone itself. One reason for this would be for the mobile telephone system operator to know this so that a different tariff can be applied to this call than to a call made from the mobile telephone itself. This may be done, for example, by using the SMS signalling facility, or by providing the mobile telephone with two different numbers which it can use for normal and intercepted calls respectively. In a simple form of the system, if the mobile telephone system operator decides not to accept the call, the mobile telephone system may simply not accept the call without sending back any particular signal; the control unit will recognize that situation, eg by means of a timer, and couple the call to the PSTN.

The docking station will normally only intercept calls if the mobile telephone is in it. However, the mobile telephone and the docking station may be coupled together by a cordless telephone type coupling, e.g. bluetooth, in which case the docking station may be set to intercept calls when the mobile telephone is within its range.

The system has been described above in terms of the functional requirements of the system. The system can of course be implemented as shown in Fig. 1, with a separate control unit being included in the system. Structurally, however, the control unit can be included in some other existing unit of the system such as the cellular telephone docking station or the base unit of the cordless telephone subsystem or distributed between them in any convenient way.

Thus Fig. 2 shows an embodiment in which the docking station 11 of the cellular telephone is connected in series with the existing land line. In this embodiment the docking station 11 includes and performs the functions of the control unit 50. Thus the docking station passes all incoming calls on the landline through to the base station 20, regardless of whether or not the mobile telephone 10 is in the base station; also, if the mobile telephone is not in the docking station, then the docking station passes outgoing calls from the cordless telephone system through to the landline.

Likewise, the link between the docking station of the mobile phone and the fixed telephone system could be in the form of a wireline link or and infra-red or radio link such as bluetooth. Also, if desired, the mobile telephone 10 can be of a type which can communicate with more than one mobile telephone system operator.

Fig. 3 shows a further embodiment in which the cordless telephone base unit 20 is connected in series with the existing land line. In this embodiment the base unit 20 includes and performs the functions of the control unit 50. Thus the base unit passes all incoming calls on the landline through to the cordless telephone handsets 21 and 22 and the fixed telephone handset 31, regardless of whether or not the mobile telephone 10 is in the base station 1 1 ; also, if the mobile telephone 10 is not in the docking station 1 1 , then the base unit 20 passes outgoing calls from the cordless telephone system or the fixed telephone handset through to the landline.

It is obvious that the systems as shown in Figs. 1 to 3 can be simplified in various ways. For example, the cordless telephone subsystem can be a simple single cordless telephone and its base unit, the fax machine

46 and/or answering machine 47 can be omitted or replaced by one or more further handsets, fixed and/or cordless, etc.

It has been assumed so far that the mobile phone 10 can communicate with only a single mobile telephone system operator. However, with suitable design it can communicate with a plurality of different operators. The control unit will then preferably include means for selecting between the different operators, either in a fixed order or in an order determined by the different tariffs or other characteristics of the different operators.

The present system allows the mobile system operator to offer terms which are competitive to existing land based networks; it reduces the cost to the user of using the system; and it reduces the loading on the PSTN system. To implement the system, no additional land-lines are required to be installed to the premises. Such additional lines that are required are inside the premises and may be connected to ordinary telephones or to a cordless telephone base station.

Claims

1 A telephone system comprising cellular telephone means, a fixed telephone system coupled to a PSTN, and call interception means operative when the cellular telephone means are operative for detecting when a call is being initiated on the fixed telephone system and for diverting that call to the cellular telephone means under the control of the cellular telephone system operator.

2 A telephone system according to claim 1 , wherein the cellular telephone means comprise a mobile cellular telephone and a docking station therefor, and the call interception means is operative only when the mobile telephone is coupled to the docking station.

3 A telephone system according to claim 2, wherein the call interception means is operative only when the mobile telephone is physically engaged with the docking station.

4 A telephone system according to either previous claim wherein the fixed telephone system includes a cordless telephone unit.

5 A telephone system according to claim 4 wherein the call interception means are located in the cordless telephone unit.

6 A telephone system according to any of claims 1 to 4 wherein the call interception means are located in the docking station. 7 A telephone system according to any of claims 1 to 4 wherein the call interception means are located partially in the cordless telephone unit and partially in the docking station.

8 A telephone system according to any of claims 1 to 4 wherein the call interception means are distinct from the cordless telephone unit and the docking station.

9 A telephone system according to any previous claim wherein the call interception means filters its call interception.

10 A telephone system according to claim 9 wherein the filtering includes inhibiting call interception at full-rate times.

11 A telephone system according to either of claims 9 and 10 wherein the filtering includes inhibiting call interception of certain types of calls.

12 A telephone system according to any of claims 1 to 8 wherein the control unit determines whether to divert a call by exchanging information with the mobile telephone system operator via the mobile telephone.

13 A telephone system substantially as herein described with reference to the drawings.

14 The call interception means of any previous claim.