Nongaussian Effects in DS/SSMA Communications

Performance of digital linear correlation receivers is studied in a multi-user environment. There are assumed to be two types of sources interfering with data transmission; multiple-access interference, and additive channel noise, which is attributed to non-Gaussian sources in the environment. The contribution of multi-user interference is examined by considering K users transmitting over a channel using the binary PSK direct-sequence SSMA technique. However, the effects of the non-Gaussian channel in such systems is studied by modeling the samples of noise after front-end filtering. To compare the significance of the two interferers, the integration of the characteristic function method is used to compute the average bit error probability. The results indicate that in most of the noise models considered, the degradation in error probability due to the non-Gaussian nature of the noise is more than that due to the interference of extra users sharing the channel.