Performance of pulse-position modulation with trellis-coded modulation on non-directed indoor infrared channels

We examine the performance of high-speed non-directed infrared links using pulse-position modulation (PPM) with trellis-coded modulation (TCM) to mitigate the effects of multipath-induced intersymbol interference (ISI) on such links. Using the measured characteristics of multipath indoor infrared channels, we calculate BER curves and ISI power penalties for maximum-likelihood sequence detection of 8-PPM links using rate-2/3 trellis codes operating at 10 and 30 Mb/s. Our results indicate that TCM is a very promising coding technique for L-PPM on high-speed non-directed infrared channels.