Phase Estimation Technology And Test Verification Research Of Intradyne Coherent Optical Receiver

Coherent detection is one of the main technology to achieve high receiving sensitivity.It's the research hotspot and frontier in the field of wireless optical communication.Intradyne detectio combine the advantages of the homodyne which has minimum signal processing bandwidth and heterodyne reception which don't need optical phase-locked loop.its technical characteristic is to achieve high receiver sensitivity while phase noise exists.Carrier synchronization is the key technique of intradyne coherent detection.Frequency estimation and phase estimation is studied in a 200 Mbps binary phase-shift keying system in this article.The purpose of this article is to achieve high receiver sensitivity while frequency offset and phase noise exists in the limitation of this article.The full text is as follows:First,In this paper,the dynamic analysis of coherent detection is carried out,and the main technical route and technical difficulties of coherent detection is analyzed.The characteristics of classical coherent detection and reception technology are analyzed and summarized,and the research goal of this paper is determined.Second,the structural characteristics of coherent optical communication system(homodyne reception,heterodyne reception,intradyne reception)is analyzed,intradyne reception system is the main research object.The main algorithm and basic principles of intradyne reception like clock recovery and carrier recovery is analyzed.This paper focused on the frequency offset estimation algorithm and phase estimation algorithm discussion and analysis.Thirdly,the scheme design of the frequency offset estimation algorithm and the phase estimation algorithm of the intradyne reception system is completed.The feasibility and validity of the phase estimation algorithm are verified by the simulation analysis method.Fourthly,this paper completes the software coding and debugging of the clock recovery,frequency offset estimation and phase estimation algorithm of intradyne coherent detection,and completes the realization of digital circuit based on FPGA.The test results show that the algorithm of frequency offset estimation and phase estimation are feasible and effective.The results show that the proposed algorithm is effective and effective.The experimental platform of intradyne coherent optical communication based on BPSK modulation is constructed and real-time signal processing of intradyne optical communication is realized.Link-level test is carried out for intradyne coherent detection and receiving system.The proposed frequency offset estimation algorithm and phase estimation algorithm are feasible and effective to meet the requirements of this paper.