Turbo decoding performance of spectrally efficient RS convolutional concatenated codes

Reed-Solomon convolutional concatenated (RSCC) codes have been widely used in wireless and space communications. Turbo decoding of the concatenated code has been recently developed and shown that the code's error-correction capability can be significantly improved. Particularly, turbo decoding of RSCC codes yields a competent performance when the codeword length is limited. This makes the code a very good candidate for certain communication scenarios in which short packet length is preferred and strict decoding latency and energy consumption constraints are applied, such as the wireless sensor networks (WSN) and high mobility communications (HMC). However, code concatenation inevitably results in rate loss which affects the transmission spectral efficiency. Therefore, this paper investigates the turbo decoding performance of RSCC codes that is integrated with high order modulation schemes to realize spectrally efficient transmissions. The EXtrinsic Information Transfer (EXIT) analysis of the turbo decoding mechanism is performed in order to design the inner convolutional code which can optimize the concatenated code's error-correction performance. Our simulation results obtained in both the additive white Gaussian noise (AWGN) and Rayleigh fading channels show turbo decoding of RSCC codes achieves significant performance improvements over the existing non-iterative decoding schemes.