ADAPTIVE ENCODING MODE CONTROL METHOD AND APPARATUS IN A TDMA RADIO COMMUNICATION SYSTEM

摘要

A power control system in a TDMA radio communication system has traffic channels which are associated with a set of speech/channel encoding modes. Each mode has a different mix of speech encoder bit rate and data protection bit rate but the same total available gross bit rate. The transmitter includes a power control unit (34) that replaces a mode allocated to a channel by another mode having higher (lower) data protection bit rate and lower (higher) speech encoder bit rate if the sound to be encoded requires a lower (higher) speech encoding bit rate. The power control unit also controls a power adjustment unit (36) that reduces (increases) the output power of the transmitter to a lower (higher) level such that an estimated decoded speech quality measure (CTRL) at the receiver is essentially constant.