Design Of Digital Carrier Synchronization Loop

Because of its characteristics of carrier tracking,modulation tracking and high frequency stability,the carrier synchronization loop has been widely used in the main radio equipment of electronic equipment,navigation,communications,radar and so on.Application areas.Aiming at the characteristics of large frequency offset in satellite communications,it is a key challenge in satellite communication to design a large-frequency-offset carrier synchronization loop that is in line with system specifications.The design of large-frequency carrier synchronization loop has a direct impact on the performance of the satellite communication system.This paper introduces in detail all the indexes involved in the design of large-frequency offset carrier synchronization loop.The thesis first introduces the development history and research status of carrier synchronous loop,and then based on its basic working principle,based on the structure of traditional carrier synchronous loop,the tracking performance,acquisition performance and stability of carrier synchronous loop Noise performance and other performance were analyzed.The various parameters of the carrier synchronization loop were deduced in detail,and the conclusion of the mathematical analysis of the carrier synchronization loop was obtained.From this conclusion,the mathematical model of carrier synchronization loop is obtained.Then it describes in detail how to transform discrete signals in frequency domain in digital domain.Innovative use of the mathematical model of the carrier synchronization loop combined with the complex discrete-time signal frequency domain transform algorithm to build a large carrier frequency carrier synchronization loop Matlab simulation model,the simulation of the large frequency offset carrier synchronization loop mathematical model in Matlab to determine the subject Large frequency offset carrier synchronization loop in accordance with the design requirements of the various parameters of the value.It effectively solves the problem of fast carrier tracking and locking difficulties under relatively fast communication conditions with relatively large displacement and large Doppler shift.The technology can be applied to car moving in the airborne satellite receiver and other projects.In AD / DA,FPGA \ DSP hardware architecture based on the theory of software and radio technology and MATLAB simulation results,the use of AD sampling data inthe FPGA to achieve all-digital large-carrier frequency synchronization loop,complete satellite carrier capture Synchronize with tracking.