Signal demodulation method for underwater optical wireless communication by measuring the time interval between adjacent photons

We proposed a signal demodulation method by measuring the time interval between adjacent photons and realized the recovery of the original signal from the discrete random pulse sequence output by the single-photon detector. On this basis, a new communication system model is established by comprehensively considering the photon statistical characteristics of the emitted light field, the statistical distribution of adjacent photon time interval and the performance of the detector. Finally, an underwater optical wireless communication (UOWC) system was built. The effects of the average time interval between adjacent photons, baud rate and demodulation threshold in the time-slot on the system bit error rate (BER) were verified by experiments. The experimental results show that when the baud rate is 100 Kbps and the average time interval between adjacent photons is 111 ns, the BER of the system is 2.52?×?10^?5.