A rate-adaptive concatenated coding scheme

The scheme is based on the rate-adaptive RS (Reed-Solomon) Code As The Outer Code, And The Convolutional Code, as the inner code. The throughput and error probability for this scheme are derived. As an example, the scheme is applied to the Rayleigh fading channel and is compared to the system using only the rate-adaptive RS code. In both cases a maximum of four transmissions for each codeword is assumed. It is shown that, by using a 1/2 rate memory m = 3 systematic convolutional code (with hard decision decoding) in conjunction with a (60,26) RS code, a 2-dB improvement is achievable, compared to a rate-adaptive RS code. It is also shown that applying soft decision to the Viterbi decoder has a 4-dB advantage over the hard decision decoding.>