Performance analysis of T-PPM over PPM for infrared wireless links

Current designs for deep-space optical communication systems utilize M-ary pulse position modulation for direct-detection photon communications over unguided channels. The analysis of a trellis-based pulse position modulation (T-PPM) scheme for photon communications with non-rectangular pulses is presented. The scheme includes the use of a set-partitioning methodology to increase the minimum distance using a simple convolutional encoder. It has been shown that T-PPM reduces performance losses due to reduced peak intensity during the detection process.