大多普勒频偏SOQPSK信号FFT引导COSTAS环载波跟踪技术  

SOQPSK Carrier Tracking Technology with Large Doppler Frequency Offset Based on FFT Guided Costas Loop

作　　者：王旭东[1,2] 樊涛[1] 黄强辉[2] 郑步生[1] 

机构地区：[1]南京航空航天大学电子信息工程学院,江苏南京210016 [2]南京长江电子信息产业集团有限公司,江苏南京210037

出　　处：《电子学报》2016年第2期491-496,共6页Acta Electronica Sinica

基　　金：国家自然科学基金(No.61201208);中国博士后科学基金(No.2014M561643);江苏省产学研联合创新资金项目(前瞻性联合研究)(No.BY2014003-05)

摘　　要：SOQPSK信号包络恒定、相位连续,拥有很高的功率、频谱效率,在卫星通信、深空通信、航空遥测等系统中具有广泛的应用前景.为保证SOQPSK信号能够适应上述系统较大的载波多普勒平移,本文提出一种FFT引导COSTAS环的SOQPSK信号载波跟踪技术.算法首先利用FFT粗略估计多普勒频率,将载波频偏牵引至较小的误差范围,再利用改进的COSTAS环跟踪载波残差及相位误差,进而实现了对大频偏SOQPSK信号载波的稳态跟踪.仿真结果表明,本文所提算法不仅能够跟踪大频偏载波,而且在小频偏时性能亦优于传统方法.SOQPSK signal has constant envelope and continuous phase,and has high power and spectral efficiency. It will have broad application prospects in satellite communications,deep space communications and aeronautical telemetry systems. To ensure SOQPSK carrier signal can be applied to larger Doppler offset system,this paper presents a SOQPSK signal carrier tracking technology which uses FFT guide COSTAS loop. First,a rough estimate by FFT of the Doppler frequency makes carrier frequency offset be limited to a small range,and then uses the improved COSTAS loop to track carrier residuals and phase error,thus achieving a steady carrier track for SOQPSK signal with large carrier frequency offset. Simulation results showthat the proposed algorithm not only is able to track large carrier frequency offset,but also is better to track small frequency offsets than traditional methods.

关 键 词：恒包络 SOQPSK FFT COSTAS环 大频偏 载波跟踪 

分 类 号：TN911[电子电信—通信与信息系统]