Iterative Coded Multipulse Pulse Position Modulation for High Data Rate Optical Space Communication

We present a modulation and coding scheme comprised of the serially concatenation of a convolutional code, interleaver, accumulator, and Multipulse pulse position modulation (MPPM) or Serially concatenated MPPM (SCMPPM) for high data rate optical space communication. It is decoded with an iterative demodulatordecoder, using standard turbo-decoding techniques. The Serially concatenated pulse position modulation (SCPPM) has been demonstrated to give the best performance on a space optical link modeled as Poisson channels. We compare the performance of both systems at the same transmission bandwidth and information bits transmitted per modulation symbol on the same link. It is shown that, compared to the SCPPM, the SCMPPM provides better Bit-error rate (BER) performance when operating under a peak power constraint, and is able to achieve higher data rates. Hence, the SCMPPM can be applied to high data rate optical space communication systems where bandwidth and peak power are restricted.