System and method for performing combined multi-rate convolutional coding

Abstract

A system and method for establishing an integrated forward error correction (FEC) scheme to perform multi-rate encoding on different priority data bits of a channel access message transmitted on a random access channel between devices of a communications network, such as between an access terminal and a base station of a satellite-based communications network. The channel access message includes a first data group representing first information and a second data group representing second information, which is transmitted between an access terminal and a base station in a satellite-based communications network. The system and method encodes the second data group at an encoding rate to provide a second encoded data group, and encodes the first data group at the same encoding rate to provide a first encoded data group. The encoding of the first and second data groups is performed by a single encoder, such as a rate ¼ convolutional encoder. The second encoded data group is transmitted from the access terminal to the base over a random access channel. The second encoded data group further can be punctured during transmission to in effect decrease its coding rate, for example, to rate ½ coding. The first encoded data group is transmitted from the access terminal to the base station, and is then retransmitted from the access terminal to the base station to in effect increase the rate of coding of the first encoded data group to, for example, ⅛ coding. At the base station, a combiner/demodulator combines the transmitted and retransmitted first encoded data group, and the combined first encoded data groups and the second encoded data group are then decoded by a decoder.