Cordless telecommunications installation with cordless telephone appts. - has installation and telephone appts. linked via subscriber coupling lines, to which base station and cordless handset are coupled.

Cordless phones are increasingly used as powerful supplement used with existing wired telephones. Such phones consist of a basic apparatus, which as with the telephone network, known by wire is connected and a handset, the cable is replaced by a radio link to the base apparatus. The radio transmission distance is less than 300 m outdoors Grounds and buildings only up to 50 m.

Applications for such phones are z. B. cordless Home central systems, which have a microcell structure, each connected phone only in its radio area can be operated.

Another application is with Business Cordless Telecommunications designated and includes systems that a full functionality wireline telecommunications system for the cordless Telephone devices provides. In addition to a user with such phones in the entire area covered with full can move freely accessibility.

Such a system has a cordless extension that a plurality of base stations controls. These base stations supply all cordless handsets, which within itself a cell reside.

The aforementioned applications are known from "Technical Rundschau ", 51/52, 1989, pages 36 to 39, Cordless Telecommunications in the workplace, by Heinz Ochsner.

In the known cordless telephones (CT1, CT1 + CT2) is any Telephone assigned a single cell, the cordless Handset a unique identifier within the is radio range of the associated base station operable.

Imports accompanied by an expansion of telecommunications system operates, in principle, according to the public cellular radio system, so that a participant freely within the cell structure can move covered brain area. However, this solution is very consuming, since at any time the location of the plurality of cordless must be known handsets.

The present invention is based on the object, a Telecommunications system having a plurality of cordless to provide telephone sets such that a cellular structure without substantial changes to the used Telecommunication system is implemented.

This object is inventively achieved by the technical teaching of Patent claim 1.

Since according to the invention in the telecommunication system for each Number of a base station and the associated identification number of the Handset is stored, since on the air interface the base station identification number is sent only, at any time of called subscriber, regardless of which one of the lobby Plurality of base stations it is located, are determined.

Thus, in advantageously cordless handsets, the z. B. work to DECT standard (because the identification number = PIN sent is) used, said in an inexpensive kind of the Features "roaming" and "hand over" can be realized.

Further advantageous embodiments of the subject invention are disclosed in the dependent claims.

Next, referring to the drawings, an embodiment explained.

The figure shows schematically an inventive Telecommunication system.

A telecommunication system TK, as shown in the figure, with a plurality of cordless telephone sets connected. The Telephone sets each consist of a base station BS1, BS2, BS3. , , , Which, via subscriber lines L1, L2, L2. , , , as conventional wireline telephone sets to the Telecommunication system TK are connected. Each base station BS1, BS2, BS3. , , is a cordless handset HS1, HS2, HS3, assigned so that each cordless telephone set a Radio cell spans, and thus a total of a cellular structure is formed.

The cordless telephone sets may according to the DECT standard (Digital European Cordless Telephone) to be built up, each Base station BS1, BS2, BS3. , , a telephone number 4711, 4712, 4713, is assigned and each cordless handset HS1, HS2, HS3, , , , a unique identification number PIN (Personal Identification Number) (PIN = xx, xy = PIN, PIN = xz,...), So that the cordless handset can be called by its PIN.

The following describes with reference to the figure of the end, as According to the invention for an incoming call, the associated cordless Handset, no matter the transmission range (cell) a Base station they happen, is and without accessing the that any information about the current location must be present. are only for this case in the figure necessary parts of the telecommunication system from the perspective of Sequence is shown schematically.

A subscriber A wants to connect to a subscriber B, z build here. B. with the cordless handset HS1. First is the number of 8-subscriber, the call number of 4711 associated base station BS1 selected. According to the invention now the telecommunication system TK storage means SP in which the Telephone numbers of the base stations BS1, BS2, BS3. , , and the Identification number PIN of the associated cordless handsets HS1, HS2, HS3. , , are stored.

There are thus, as the figure shows, the following assignments for the cordless telephone sets stored:BS1-HS1 4711 PIN = xxBS2-HS1 4712 PIN = xyBS3-HS1 4713 PIN = xz.

With the aid of control means ST telecommunications facility TK, which in the usual way for the entire connection setup / degrading are, is now due to the incoming call from the A-subscriber for the telephone number 4711 in the storage means SP the associated Identification Number PIN = xx determined. The control means ST send then, see. the figure, the determined PIN = xx of this B subscriber HS1 z. B. As a subaddress of the call numbers of the plurality of base stations, to all base stations via the subscriber lines L1, L2, L3,. , , out.

Thus, as shown in the figure, each base station BS1, BS2, BS3. , , called, then the latter through its air interface the determined identification number PIN = xx emits. If now the looking handset HS1 (PIN = xx) as shown in the transmission range the second base station BS2 is located, then the called Identification Number PIN = xx with its own identification number PIN = compared xx, and due to the conformity of the numbers is the cordless handset HS1 take the call, so that, controlled for by the control means ST a connection from the A-subscriber B-subscriber is hergesellt.

Thus, with very simple means Anytime Participants with cordless handsets HS1, HS2, HS3. , , , Regardless of the cell a base station BS1, BS2, BS3. , they are right now, accessible. According to the invention namely always in the Storage means the identification number PIN to the number 4711, 4712, 4713,. , ready, so that the phone number the calling the Participants will be presented, always the identification number PIN of the Handset and not the phone number of the base station. In order to is that known as "roaming" feature through the Telecommunication system TK invention in a simple and met cost-effective manner.

In addition, also called "hand over" is known Feature realized by the inventive system. If, after setting up a connection A subscriber to subscriber B Here the B-subscriber with his cordless handset HS1 to from the coverage area of ​​the second base station BS2 through which the instantaneous connection has been moved out, so will According to the invention the cordless handset HS1 a request to Maintaining the connection to the control means of the ST Telecommunication system TK send. The control means ST is then the per se known feature "Holding a compound" automatically call and after the participants with the cordless handset HS1 first in the reception area of ​​the z. B. moving base station BS1 has (evaluation of field strength by Handset) is automatically a request with the identification number PIN = xx via the first base station BS1 to the control means ST transmitted, which is then the connection via the first base station BS1 switches through the cordless handset HS1. Thus, although the Handset HS1, the base station switches remains invention the call number display at A-subscriber right there, the Identification Number PIN = xx on the telephone number 4711 (from previously 4712) is displayed.

Of course, any connections between cordless handsets HS1, HS2, according as before described for a wired to a wireless Station set executable.