Iterative demodulation and decoding for parallel combinatorial SS systems
K. Takizawa, S. Sasaki, Jie Zhou, Shogo Muramatsu, Hisakazu Kikuchi · 2002
This paper proposes iterative demodulation/decoding for parallel combinatorial spread spectrum (PC/SS) systems. The PC/SS systems convey the information data by a combination of pre-assigned spreading sequences with polarity. Convolutional coding with a random interleaver is implemented as channel coding, like serial concatenated coding. A 'soft-in/soft-out' PC/SS demodulator, based on an a posteriori probability algorithm, is proposed to perform the iterative demodulation and decoding. Simulation results demonstrate that the proposed iterative demodulation and decoding bring significant improvement in the bit error rate performance.