Alcatel Cit

Alcatel Mobile Communication France

Alcatel N.v.

Matra Communication

Societe Dite Alcatel N.v.

Marc Delprat

Evelyne Le Strat

Frederic Gourgue

Philippe Mege

Christophe Mourot

Fabrice De Seze

Vianney Andrieu

Jean-Louis Dornstetter

Eric M Pequet

Charles Nouchi

Gladys Gaydu

A mobile radio system enables exchange of bidirectional digital signals between at least one mobile station and at least one base transceiver station and provides at least two coding modes, each mode corresponding to a predetermined source code and a predetermined channel code for the transmission of a wanted signal for each transmission direction. Each source code corresponds to a given user bit rate and each channel code corresponds to a given coding efficiency and therefore to a given total bit rate for a given source code. For adaptation of the air interface of this system, at the time of a call between a mobile station and a base transceiver station, two separate analyses of transmission quality are carried out for each transmission direction, respectively, and, for each transmission direction, one of the coding modes is selected in accordance with the corresponding transmission quality analysis.

Method of adapting the air interface and mobile radio system and corresponding base transceiver station, mobile station and transmission mode

A channel selector device for a multiple access system of direct transmission between mobile stations carries out measurements on various channels during calls in order to determine if there is a better channel than the traffic channel used for the call. This better channel constitutes the new traffic channel to be-used.

Channel selector device for multiple access direct transmission systems between mobile stations

Method of adapting the air interface in a mobile radio system and corresponding base transceiver station, mobile station and transmission mode

Method of adapting the air interface in a mobile radio system and

Air interface adapting method for a mobile radio system

In a digital half-duplex frequency division multiple access radio system a mobile station is either sending or receiving. For each call between a mobile station and a base station, a first frequency is allocated for the up link direction (from the mobile station to the base station) and a second frequency is allocated for the down link direction (from the base station to the mobile station). The signals exchanged by the stations are organized in frames of predetermined fixed duration grouped into multiframes comprising a predetermined number of frames including at least one control frame. At least some of the control frames are listening frames during which the sending mobile station interrupts sending, switches to receive mode and (if appropriate) reverts to send mode.

Frame/multiframe structure FDMA system and corresponding signal

The present invention relates to a dummy burst structure used in a cellular digital radio-communications system operating on the principle of time division multiple access, each cell in the system being associated with a beacon frequency subdivided into periodically-repeated frames, each of which comprises at least one signalling channel or beacon path for transmitting signalling messages to mobile stations, the other channels serving in particular to transmit useful data, the burst being transmitted over those channels of the beacon frequency which are not assigned to transmitting useful data, or over certain time slots of the signalling channel when there is no signalling data to be transmitted over the certain time slots, wherein the burst contains a signalling message.

Dummy burst structure in a cellular digital radio-communications system

In multiplexed data radio communication, especially (but not exclusively) in TDMA mode, a method is provided of offering optimized intelligent traffic channel sharing services, enabling data from a secondary source to be conveyed on a traffic channel assigned to a main source (20, 30, 40). Each of the blocks transmitted by the main source and the data from the secondary data source are defined by one of the least three relative levels of importance (NI.sub.p =0, 1 or 2; NI.sub.s =0, 1, or 2). Data from the secondary source is substituted for a block transmitted by the main source as the result of a comparison of the respective relative levels of importance of data from the secondary source and the block from the main source.

Method, terminal and infrastructure for sharing channels by controlled

At least one communication equipment connected to a communication infrastructure uses a first data coding format different from a second format used within the infrastructure which further comprises at least one data transcoder for converting data coded to the first format into data coded to the second format and vice versa. A transcoder is provided in the infrastructure in the vicinity of the connection to each of the equipments using the first format. The method of transmitting data between at least two of the equipments determines, on the basis of the data format used by each of the equipments between which data is to be transmitted, whether it is necessary to use a transcoder to transmit said data. If so, the transcoder nearest the equipment using the first format is activated so that the data is conveyed in a form coded to the second format in the infrastructure and changes from the first format to the second format or vice versa as close as possible to the equipment using the first format.

Method of transmitting data between communication equipments connected

According to the method, a physical transmission channel is split into a plurality of logic channels which may be dedicated to different communications. Each logic channel consists of time slots having a same duration and the same rank in successive frames of constant length. At least one of the logic channels is split into a plurality of sub-channels dedicated to different communications. Groups of k successive time slots (k being an integer greater than 1) are allocated to each logic sub-channel. The groups are time distributed in a regular way and k is so selected that N be different from (m.k+1) where m is an integer and N is the number of time intervals necessary for reconstructing an information block.

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Le Chesnay, France

Marc Delprat