摘要
根据实际工程需要，基于软件无线电的设计思想，分析了影响测控链路中解调性能的主要因素，提出了一种符号定时同步选用前馈式同步算法，载波同步选用反馈闭环结构的 OQPSK解调器的实现结构。介绍了滤波抽取及复数下变频、符号定时同步和载波同步的详细设计与实现方法。通过将2.5～80 Msps的信号解调实测，并与理论数值对比，实测结果比理论值恶化少于1 dB。OQPSK解调器结构简单，具有高度的稳定性、灵活性和可扩展性等。
In this paper,the main influencing factors on demodulation performance in TT＆amp;C Link in practical engineering are analyzed based on design idea of software defined radio. An implementation structure of OQPSK demodulator is proposed,in which symbol time synchronization selects feedforward synchronization and carrier synchronization selects feedback closed loop structure.This paper introduces the detailed design and implementation of filter extraction,complex down-converter,symbol timing synchronization and carrier synchronization.In the simulation,the signals from 2.5~80Msps are demodulated,and compared with that of theoretical values,the degradation of simulation results is less than 1dB.The OQPSK demodulator has simple structure,high stability,high flexi-bility,high extensibility,etc.
出处
《无线电通信技术》
2014年第4期42-45,共4页
Radio Communications Technology
基金
国家部委基金资助项目
关键词
OQPSK
符号定时同步
载波同步
零中频解调
OQPSK
symbol timing synchronization
carrier synchronization
homodyne intermediate frequency demodulation
