Abstract: The call hand-over technique of this invention is characterized by the use of channel information from both the target base station and subscriber terminal in determining which radio traffic channel will be used to hand over a call in progress from a serving base station to a target base station. Calls are handed over to the radio channel which, of a set of channels under consideration by the subscriber terminal, contains the least amount of interference as measured by the subscriber terminal. The set of channels under consideration by the subscriber terminal is a subset of the entire set of channels allocated to the service. This subset is comprised of those channels having little interference, as measured by the target base station. The hand-over technique thereby assures that calls proceed on channels containing little interference from the viewpoints of both the target base station and subscriber terminal.

Abstract: The intra-cell call hand-over technique of this invention is characterized by the use of channel information from both base station and subscriber terminal in determining a standby radio traffic channel upon which to hand over a call. Communication between the base station and subscriber terminal is carried out on an inband or associated signalling channel for the selection of the standby traffic channel. The standby radio channel is the channel, which, of a set of channels under consideration by the subscriber terminal, contains the least amount of interference as measured at the subscriber terminal. The set of channels under consideration by the subscriber terminal is a subset of the entire set of channels allocated to the service. This subset is comprised of those channels having little interference as measured by the base station. The call hand-over technique thereby assures that calls proceed on channels containing little interference from the viewpoints of both base station and subscriber terminal.

Abstract: An improved radio link architecture for digital wireless communication systems which is characterized by the use of information and signalling channels on a number of RF carriers, thereby providing common signalling channels for call set-up and control functions. A first group of RF carriers are allocated as traffic channels between base stations and subscriber terminals. Each RF carrier in the first group comprises at least one traffic channel. A second group of RF carriers is allocated for providing common signalling channels between the base stations and the subscriber terminals. Each RF carrier having common signalling channels operates in time division multiple access mode, and each common signalling channel being time division duplexed.

Abstract: The present invention provides a method and apparatus of making secure conference calls in which the bridging unit does not need to know any encryption keys and can function independently of the encryption process used by the communicating parties. This means that there is no security requirement for the conference unit, there are fewer restrictions on where it can be placed, and it does not introduce any additional weaknesses in the security system.