Abstract: An uplink transmission frame transmitted from a base transceiver station to a transcoder rate adaptation unit in a cellular mobile radio network includes in the conventional way an information area in the form of at least one data field and at least one control field, the latter including a subfield representative of the validity of data transmitted in the at least one data field. This subfield is substantially at the start of the information area. This frame structure prevents transmission of invalid speech signals during a call from the cellular network to a fixed network such as the public switched telephone network at the time of handover affecting a mobile station involved in the call.

Abstract: The invention relates to a method of transmitting data over a mobile telephone speech channel between a radio telephone terminal having a type of source encoding and a data transceiver unit via a mobile telephone network supporting at least one mode of communication without transcoding that can be set up between two mobile telephones having at least one type of source encoding in common. In the method, while negotiating the mode of communication between said radio telephone terminal and said data transmitter and/or receiver unit, the transmitter and/or receiver unit sends one of the types of source encoding available to said terminal to the terminal to engage said mode of communication without transcoding. Thereafter, data is transmitted over the mobile telephone network in frames reserved for speech signals encoded using the type of source encoding selected for the mode of communication.

Abstract: An uplink frame transmitted from a base transceiver station to a transcoder rate adaptation unit in a cellular mobile radio network includes in the conventional way an information area in the form of at least one data field and at least one control field, the latter including a subfield representative of the validity of data transmitted in the at least one data field. This subfield is substantially at the start of the information area. This frame structure prevents transmission of invalid speech signals during a call from the cellular network to a fixed network such as the public switched telephone network at the time of handover affecting a mobile station involved in the call.

Abstract: A mobile radio communications system including a public system and at least one private system, and “multimode” mobile stations suitable for operating in either of said systems, in which the management of the radio resources of said at least one private system is integrated in that of said public system, the mobile radio communications system including means for conveying over a dedicated signaling channel allocated to a mobile station in cellular mode, information about radio resources allocated to said mobile station in private mode.

Abstract: A transmission frame comprises a synchronization flag and data bits. It is formed of at least a first subframe in which occur the synchronization flag and an identification field which specifies the number of subframes. Each of the other subframes comprises blocking bits disposed so that the synchronization flag cannot occur in the subframes unless in conjunction with the first subframe.

Abstract: A transmission frame comprises a locking row, synchronization bits and data bits, the synchronization bit being placed immediately after the locking row. The frame terminates with a synchronization bit. A transmitter and a receiver are linked by a transmission channel carrying these frames.

Abstract: A transmitter transmits blocks to a receiver by means of frames formed of a locking row and data rows. It receives an acknowledgement from the receiver sent by the latter on recognizing a locking row. A block comprises control bits, data bits and adaptation bits. During a first phase preceding reception of the acknowledgement the transmitter transmits blocks in which the adaptation bits have been eliminated by means of short frames comprising an initial number of data rows. During a second phase following on from reception of the acknowledgement it transmits blocks incorporating the adaptation bits by means of complete frames comprising a final number of data rows which is greater than said initial number. The receiver includes an analyzer for determining if the blocks are conveyed by a short frame or by a complete frame in order to identify the nature of the blocks.

Abstract: The invention relates to a method of managing transmission errors between a base station and a transcoder, in a digital radiocommunications system for mobile stations, in which method the transcoder, in the presence of a transmission error, systematically inserts (29, 221, 228) an error message in a frame addressed to the base station without interrupting useful data transmission to the base station, and in which method the base station decides to interrupt data transmission to the transcoder (down direction) and generates an up-direction transmission interruption request when the transmission errors detected in the down direction and/or reported by an error message in the up direction satisfy predetermined conditions. In this way, all call-interruption decisions are centralized in the base station.