Liu Penghu, Ao Faliang, Yang Zhicheng. Error performance analysis of TCM code in PPM-based optical communication systems[J]. 2008,(2):14-17. DOI: 10.13756/j.gtxyj.2008.02.014.
Trellis Coded Modulation(TCM)is introduced into PPM to investigate the error performance improvement in optical Pulse Position Modulation(PPM) systems.Theoretical deduction and MATLAB simulation and comparisons of 8T-PPM with 16 PPM and 16T-PPM with 32 PPM respectively
produce the following results.When the bandwidth is kept constant
8T-PPM and 16 PPM have the same information rate
but the error performance of the former is better than the latter
up to 4.8 dB at the maximum.On the other hand
the information rate of 16T-PPM is 1.2 times that of 32PPM
but it has better error performance
up to 3.4 dB at the most.These results prove that the introduction of TCM into PPM does effectively improve the error performance of the system.