A Fine Synchronization Method for Coherent Fast Frequency Hopping  

作　　者：Xuanhe Yang Weike Zhang Shixun Luo Chang Li Xiaqing Miao Aihua Wang 

机构地区：[1]School of Information and Electronics,Beijing Institute of Technology,Beijing 100081,China [2]96901 People’s Liberation Army(PLA)Troops,Beijing 100000,China [3]School of Cyberspace Science and Technology,Beijing Institute of Technology,Beijing 100081,China

出　　处：《China Communications》2023年第10期163-184,共22页中国通信（英文版）

基　　金：funded by National Scientific Foundation of China under grants(No.62101050 and No.62001022).

摘　　要：Coherent fast frequency hopping(CFFH)is attracting growing attention owing to its good antijamming performance and the coherent combining ability.However,compared with the conventional non-coherent fast frequency hopping,CFFH requires a more precise system synchronization.In this paper,we propose a new fine synchronization algorithm for CFFH.This algorithm consists two stages,namely,open-loop stage and closed-loop stage.In the openloop stage,a grid-based search parameter estimation method is proposed.In the closed-loop stage,we construct a fully coherent phase-locked loop(PLL)and a delay-locked loop(DLL)with decoding feedback structure to perform further fine estimation of the system clock skew and time delay,respectively.Moreover,we analyze the effect of the search parameter settings on the estimation error and derive the root mean squared error(RMSE)of estimates in the steady state of the closed-loop stage.Finally,through simulation,the RMSE performance are compared with the corresponding Cramer-Rao low bound(CRLB)and conventional code loop estimation to show the effectiveness of proposed algorithm.

关 键 词：fast frequency hopping(FFH) spread spectrum communication fine synchronization 

分 类 号：TN914.41[电子电信—通信与信息系统]