A concatenated coded modulation scheme for error control

The authors present a concatenated coding modulation scheme for error control in data communications. The scheme is achieved by concatenating a Reed-Solomon outer code and a bandwidth-efficient block inner code for M-ary PSK (phase shift keying) modulation. The error performance of the scheme is analyzed for an AWGN (additive white Gaussian noise) channel. It is shown that extremely high reliability can be attained by using a simple M-ary PSK modulation inner code and a relatively powerful Reed-Solomon outer code. A simple method for constructing block codes for M-ary PSK modulation is also presented. Some short M-ary PSK codes with good minimum-squared Euclidean distance are constructed. These codes have a trellis structure and hence can be decoded with a soft-decision Viterbi decoding algorithm. The proposed scheme is particularly suitable for high-speed satellite communications for large file transfer where high reliability is required.<>