Abstract: The present invention relates to the technique of handover in mobile telephony. A new Transcoder and Rate Adaptation Unit (100 FIG. 3) is introduced which provides two uplink (230, 250 respectively, FIG. 3) and two downlink (240, 260 respectively, FIG. 3) channels. The use of these two channels (230, 250 respectively, FIG. 3) on the uplink during handover provides for the use of distributed handover on the uplink. The result minimizes the audible interruption during handover by minimizing the loss of Traffic Channel frames to what is possible within the GSM standard. Additionally, interruption of the speech or background noise during these lost frames is masked by an error concealment algorithm, since the Transcoder and Rate Adaptation Unit (100 FIG. 3) still has information from the Base Transceiver Station responsible for transmission before the handover.

Abstract: Techniques for enhancing radiocommunication systems, e.g., radio local loop systems, are described. Radio local loop systems replace a portion of the wired connections between a local exchange and, for example, a telephone set, with a wireless connection. Like conventional wired systems, remote unit mobility is limited. However, the present invention supports system reconfigurations, such as cell splitting, in a manner which obviates the conventional necessity of reprogramming each remote unit in a radio local loop system. Backup cells can also be provided to enhance system reliability.

Abstract: A communications system includes a receiver and a transmitter for transmitting a communications signal to the receiver. The transmitter adjusts its transmission power level in response to receiver power control signals transmitted by the receiver. The receiver includes an attenuator for attenuating the received communications signal, and measurement circuitry for measuring the signal strength of the attenuated signal. The measured signal strength is coupled to an attenuator controller and to a transmission power controller. The attenuator controller and the transmission controller adjust, respectively, receiver attenuation and transmitter power level so as to optimize system performance. This may include keeping the attenuated signal within the dynamic range of the receiver.