Maximum Likelihood Demodulation of PPM Signals for All Digital Receivers

As a laser communication modulation scheme, PPM has the advantages of high power transmission efficiency and anti-jamming performance. In this paper, it is introduced that the basic principle of PPM and the algorithm of PPM maximum likelihood demodulation for all digital receivers. And the approximate PPM maximum likelihood demodulation algorithm is proposed which is more suitable for hardware implementation. The simulation results of the approximate maximum likelihood demodulation algorithm are presented and analyzed. A method to implement the proposed demodulation algorithm in FPGA is provided and tested in laboratory environment, which verifies the correctness and reliability of the design in all digital receivers.