Coded-Sequence Self-Encoded Spread Spectrum Communications

Self-encoded spread spectrum (SESS) employs non-deterministic spreading codes that have been generated from the random information source and provide unique advantages over traditional pseudo-random codes. In previous work we have shown that the memory in SESS-modulated signals not only can deliver a 3dB gain in AWGN channels, but also can be exploited to achieve time diversity and robust bit-error rate (BER) performance in fading channels. In this paper, we propose an extension to SESS, namely coded-sequence self-encoded spread spectrum (CS-SESS), and showed that it can further improve the BER performance. We describe the CS-SESS scheme and present the theoretical analysis and simulation results of the BER performance under AWGN. We also develop an iterative detector and show that it can achieve the expected 4.7dB gain with a complexity that increases linearly with the spreading sequence length.