To provide a method and apparatus for selecting error correction code rates, in a cellular radio communication system.
Each base station broadcasts a power product (PP), which is equal to the base station transmission power PBT, multiplied by the intended power level received PBR. A mobile unit determines its appropriate transmit power, PMT (24), by measuring the power received, PMR and calculating PP/PMR. If the calculation result is greater than the maximum transmit power capability of the mobile unit due to larger channel path loss (25), the mobile unit uses the lower code rate to adjust the transmit power (27 and 31). In a preferred embodiment, 3 types of code rates 2/3, 1/2, and 1/3 are used, based on the channel path loss. The code rate selection can be based on the transmitted data volume (30, 33, 34). The base station can decode all the code rates, choose the best result and detect the code rate by decoding all code rates.
PETRANOVICH JAMES E
HARDIN C THOMAS
