Abstract: A method for managing a degraded mode of a cell of a cellular network including a site controller for controlling, via a packet network, transmitters distributed over various sites of the cell such that transmitters implementing the same pair of frequencies over different sites form a channel which, in dynamic mode, is allocated dynamically to any communication between terminals of the cell, the channel including a master transmitter selected by the controller. The method includes, in each master transmitter on detection of a failure of the controller: switching in degraded mode of the master transmitter, by associating with the channel a predefined communication known to the terminals, and transmission from the master transmitter, via the network, of a control message informing a control console connected to the packet network of the implementation of the degraded mode so that the console participates in a communication underway in the channel.

Abstract: A method for managing a degraded mode of a cell of a cellular network including a site controller for controlling, via a packet network, transmitters distributed over various sites of the cell such that transmitters implementing the same pair of frequencies over different sites form a channel which, in dynamic mode, is allocated dynamically to any communication between terminals of the cell, the channel including a master transmitter selected by the controller. The method includes, in each master transmitter on detection of a failure of the controller: switching in degraded mode of the master transmitter, by associating with the channel a predefined communication known to the terminals, and transmission from the master transmitter, via the network, of a control message informing a control console connected to the packet network of the implementation of the degraded mode so that the console participates in a communication underway in the channel.

Abstract: The invention relates to a method for establishing a call between a first access point and a second access point, by means of a network for multipoint broadcasting. The method comprises a step for attribution (20) of a multipoint address to the call, a step for communication (30) of the multipoint address to the points of access and a step for registration (40) of the access points at the multipoint address. The access points subsequently send all the media data for the call to the multipoint address. The invention further relates to a call server and a mobile radiocommunication system which permits third parties to join conversations initiated between two parties. In particular, the invention relates to professional mobile radiocommunication systems.