R. Alves and A. Gameiro (Portugal)
Infrared, PPM, TCM coding, rate adaptation.
In this communication we consider the use of PPM based modulation methods, such as the hybrid modulation method called Amplitude and Pulse-Position Modulation (APPM) and Overlapping Pulse-Position Modulation (OPPM) to improve the performance of infrared WLAN’s, by the use of Trellis-Coded Modulation (TCM) codes. We derive the best codes for some APPM and OPPM schemes, and the results show that non-negligible coding gains without bandwidth expansion can be obtained with trellis codes of moderate complexity. The theoretical coding gains are confirmed by simulation. Finally a set of multirate systems using the derived TCM coding are evaluated, and their practical benefits observed in terms of connectivity improvements.
Important Links:
Go Back
