Method for communicating calls

The invention relates to a method for switching calls in a telephone system with several subscriber terminals which can be connected via a central switching point and which contain at least one terminal pair consisting of a preferably wired and a preferably wireless terminal, calls can be conducted independently of one another both via the preferably wireless terminal and via the preferably wired terminal and the terminals of each terminal pair can be selected via a common subscriber number.

In the previously known method of this type, a subscriber can use a normal wired telephone on his desk as well as carry a wireless telephone, for example a cordless telephone, with him, via which he can be reached, and when things are going on outside the office from which he can hold conversations. The two subscriber circuits available for this purpose can be selected using the same subscriber number.

For example, from US Pat. No. 5,502,757, the common use of a subscriber number for a wireless and a wired telephone is already known. With the help of programmable subscriber service profiles, certain functional features of the wireless telephone are assigned to the wired telephone and vice versa under the common subscriber number. This will perform some of the wireless phone features in the same way as if the wired phone were performing them and the remainder of the features were performed as if the wireless phone were a wired phone connected to the same node.

In this way, a call that is not answered by either the wireless or wired telephone is routed to a voice mailbox, where the message is accepted and stored. The user can retrieve the stored message either through the wireless or the wired telephone.

The disadvantage of known methods of this type is that a predetermined hierarchy of call switching is established, whereby one of the terminals is always connected, for example in the case of incoming calls, while the other is switched to passive.

Furthermore, WO-A1-83 / 02380 describes a wired and a wireless telephone, which, however, are both connected to a common subscriber circuit which is connected to a telephone subscriber line. Both telephones can be reached via a common subscriber number, but calls cannot be made independently of one another. In order to avoid influencing two different radio transmission channels, the voice channels are scanned until a free channel is found that can be used for transmission. If all channels are busy, the wireless telephone sends out ringing signals, from which the subscriber can infer that he must switch to the wired telephone and continue the conversation there.

The object of the invention is therefore to avoid the disadvantages described above and to specify a method of the type mentioned at the beginning with which a faster and more reliable accessibility of a terminal pair subscriber can be achieved.

Another object of the invention is to provide a method for switching with which the most efficient and rapid connection possible between calling and called subscribers can be established.

According to the invention, this is achieved in that every incoming call intended for a pair of terminals, provided that none of the terminals is blocked for incoming calls, is signaled to both the preferably wireless and the preferably wired terminal, and the call is only sent to that terminal is conveyed, in which the handset is picked up first.

By dialing the common subscriber number, the caller has the security of dialing both terminals at the same time, so that a connection with the selected subscriber can be established very quickly, regardless of whether he is within range of the wireless or wired terminal.

If the user who first arrives at the terminal is not the one you want, a

Re-dialing can be agreed, or the call accepted by one terminal of the terminal pair is transferred to the other terminal of the terminal pair.

AT 406 815 B

In a further embodiment of the invention it can be provided that the terminal pair is reported as busy if only one or all terminals of the terminal pair is or are busy.

This makes it possible to display the status of a call being made by the subscriber to another subscriber, so that an unsuccessful attempt at dialing the other end device of the pair is avoided, as otherwise the caller could suspect that the subscriber to be dialed is actually not present.

In a further embodiment of the invention it can be provided that one terminal, preferably the wireless terminal of each terminal pair, is blocked for incoming calls.

In this way, disturbances during meetings caused by a ringing terminal can be avoided, while the other terminal can continue to receive incoming calls. The blocked device remains active for outgoing calls.

The invention is explained in detail below on the basis of exemplary embodiments.

A telephone system comprises several subscriber terminals that can be connected via a central switching center, including both analog and digital (DTS) terminals. At least one or more subscribers have a pair of terminals each consisting of a wired and a wireless terminal (cordless), and calls can be conducted independently of one another via the wireless terminal and the wired terminal. Each participant of a pair is assigned its own participant circuit.

However, it is also possible within the scope of the invention to implement a pair consisting of two wired or two wireless terminals, which is assigned to a subscriber. In the following, however, only the combination of a wired and a wireless terminal is described.

The terminals, in particular the wireless and wired terminals of each terminal pair, can be selected via a common subscriber number. This can reduce the number of calls to unoccupied terminals.

Two states of the terminal pair can be defined, one, called logon mode, establishes equality between the terminals of the pair, while the other, called logofF mode, defines a master-slave relationship of the terminals in which one terminal is passive is blocked. The logon mode consists in that every incoming call intended for a pair of end devices is signaled to both the wireless and the wired end device by ringing and that the call is only transferred to the end device on which the handset is picked up first.

Furthermore, a terminal, preferably the wireless terminal of each terminal pair, can be blocked for incoming calls in the logofF 'mode. This can be done by a key combination or, in the case of a digital telephone, by a programmable key. In this mode, for example, the wireless telephone is blocked for incoming calls, while incoming calls continue to be switched to the wired terminal.

If an incoming call is accepted via one of the two terminals, it can also be transferred to the other terminal of the terminal pair by dialing your own subscriber number or pressing a programmable key. If a function is carried out on the wireless terminal, this function is also taken over by the other terminal of the pair of terminals, regardless of whether the logoff or the logon mode is present. The end device pair is then reported as busy by a busy tone as soon as only one or all end devices of the end device pair is or are busy. Outgoing calls can still be made from a terminal that is not busy.