Research On Wireless Laser Communication System Based On DPSK Modulation And Self-differential Balance Detection

Wireless laser communication is a communication method in which a laser signal is used as a carrier to transmit information in free space.At present,wireless laser communication mainly has two communication systems: Intensity Mod ulation and Direct Detection system and Phase Modulation and coherent or non-coherent detection systems.Among them,DPSK modulation and self-differential balance detection system is an important direction of wireless laser communication technology in the future,because it has many inherent advantages,such as high detection sensitivity,simple receiver structure design and wavelength division multiplexing to achieve higher transmission rate requirements.Therefore,research on DPSK modulation and self-differential balance detection wireless laser communica--tion system has important application value.This paper first introduces the research background,significance and research progress of wireless laser communication system,then summarizes the advantages of DPSK modulation and self-differential balance detection system in wireless laser communication,and introduces its research and development,and expounds the importance to stabilize the working bias voltage in the process of laser signal modulation to use MZM.Then,the principle of modulation and demodulation of DPSK modulation and self-differential balance detection optical communication system is expounded.The working principle of key components of the basic components of the system is introduced in detail.The key technologies are summarized.After that,the preliminary schemes of the transmitting and receiving terminals of the test system were formulated,and the software simulation of the scheme was carried out,and the feasibility of the system scheme was verified.Finally,the stable control method of the working bias point of the MZM in modulation system is studied.A bias point control technique based on the average optical power slope value of the modulator output is proposed.