Compagnie Industrielle Des Telecommunications Cit-alcatel

Nortel Networks Corporation

Nortel Matra Cellular

Alcatel Lucent

Philippe Duplessis

Thierry Lucidarme

Keith Russell Edwards

Pierre Lescuyer

Yves Renaudin

Bertrand Couaillet

Philippe Delpit

Paul Vincent

Denis Jouannet

Michel Brusa

A cellular radio telecommunications system and method of operating the same is described which includes a first cellular radio telecommunications network for providing frequency division duplex radio transmissions over an air interface to one or more fixed or mobile terminals and a second cellular unidirectional radio telecommunications network which at least partly overlaps the first cellular radio telecommunications network for providing unidirectional simplex radio transmissions over an air interface to the one or more fixed or mobile terminals. At least one of access to the unidirectional second cellular network and handover of a communication supported by the unidirectional second cellular network is managed by the first cellular network. A special dedicated uplink channel may be provided in the first network for trasmitting uplink control and/or error messages of the second network.

Dual band unidirectional scheme in a cellular mobile radio telecommunications system

The invention concerns a cellular radiocommunication system comprising a network core ( ) including switches ( ), one or several gateways ( ) to external networks, subscriber management means ( ) and billing management means ( ). Several radio access networks ( ), including each base stations ( ) capable of radio communication with mobile stations ( ), are connected to the network core switches. Said radio access networks include an access network ( ) managed with the network core by a cellular operator and at least an additional access network ( ) having a substantially less extensive radio coverage and a substantially wider bandwidth than the one managed by the cellular operator. When setting up a communication with a mobile station through the network core and one of the access networks, a report message is generated specifying the access network concerned.

Method for monitoring communications in a cellular radiocommunication system, and network core therefor

The equipment has a wire interface for connection to a wire-Line telecommunication network and an air interface to communicate with mobile stations in accordance with a cellular network operating mode. Each mobile station operates in conjunction with a plug-in subscriber identity module containing parameters used to set up and/or manage the calls. The equipment also has a data reader/recorder suitable for receiving a subscriber module, reading certain parameters from it and writing to it other parameters dependent on the equipment. Telephone calls using a mobile station in conjunction with a subscriber identity module previously inserted in the reader/recorder may then be set up via the wire-line network.

Public mobile communication system compatible wireless communication system

Apparatus and method of providing a mobile communication system

Digital frequency receiver

A signal distribution signal for a time-division exchange has a distributed control architecture. Its switching network is organized as a plurality of independent planes (RXA to RXD) with terminal units (UT) and control units (UC) are connected via multiplex links (MX) and are synchronized by a time base (BDG) via clock signal distribution modules (MD). Each terminal or control unit is connected both to the switching network and to the clock signal distribution means by at least two independent parallel connections (F1, F2) each of which comprises multiplex links (MX) connected to different planes of the switching network, and at least one distribution link (D) connected to a different distribution module (MD) for each of said parallel connections connected to a given unit. Such exchanges are used for telecommunications purposes.

Signal distribution system for a time-division exchange

A digital frequency sender comprises a generator which supplies multi-frequency codes by cyclically scanning a table under the control of a time base (BT). The sender comprises a logarithmic generator (GL) which delivers single-frequency signals, a logarithmic adder (AL) which sums two single-frequency signals in compressed form, and a frequency output unit (DF) controlled by a computer (CAL). The invention is particularly applicable to time division telecommunication exchange division.

Digital frequency sender

A monitoring circuit for monitoring a digital signal generator which generates signals that are linear combinations of sinewave signals each of whose frequencies are defined by a coefficient K that is proportional to the corresponding frequency. The generator including means for storing the coefficients corresponding to all the signals to be emitted, the coefficients having an integer portion and a fraction portion whose number of digits defines the smallest possible coefficient value which corresponds to a signal of minimum frequency fm such that all signals emitted by the generator are at frequencies which are multiples of the frequency fm. The monitoring circuit includes a redundancy calculator circuit (EX, RR) connected to the output S of the generator (G), and comparator means (CC) comparing the redundancy calculated by the redundancy calculator circuit with a stored constant theoretical value.

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Colombes, France

Philippe Duplessis