Analysis of bit error rate of pulse position modulation in free-space optical communication

Abstract

Pulse Position Modulation (PPM) modulation is a widely used modulation method in free-space optical (FSO) communication, which has many medium forms. This work introduces and summarises the three main PPM modulation methods, L-ary pulse position modulation (L-PPM), L-ary differential pulse position modulation (L-DPPM), and L-ary multiple pulse position modulation (L-MPPM), and summarises their respective characteristics and suitable usage scenarios. At the same time, this study analyzes several cases of combining coding methods with PPM modulation methods and finds that the right coding method can make PPM modulation methods more valuable. In addition, receiver diversity and/or aperture averaging can both improve the connection error performance.