Experimental Study on Optical Wireless Coherent Communication

Compared with direct detection, coherent detection has the advantages of a fast response speed, high detection sensitivity, and good filtering performance. It is the key technology for improving the receiving sensitivity of optical wireless communication systems (Xingzheng Ke, Ke Dong, Optical Wrieless Communication [M]. Springer Press, Beijing, 2022). This chapter summarizes the domestic and foreign research progress in the field of coherent detection in optical wireless communication systems, and introduces the research work of Xi’an University of Technology in coherent-detection technology. It mainly includes the effects of atmospheric-turbulence suppression, arrival-angle fluctuation, amplitude fluctuation, channel noise, optical-signal polarization, local vibration light power, and light-source linewidth on the performance of coherent-detection systems. It also describes the research progress on subcarrier-modulated nonoptical extraterritorial detection systems and a performance analysis of ideal and nonideal channels. Finally, the development directions of optical wireless coherent communication systems are prospected.