基于FPGA的零中频DPSK信号解调技术研究与实现  

Design and FPGA Implementation of Zero-IF DPSK Signal Demodulation

作　　者：李雷[1] 严玉国[1] 杨宾峰[1] LI Lei;YAN Yu-guo;YANG Bin-feng(School of Information and Navigation,Air Force Engineering University,Xi’an 710077,China)

机构地区：[1]空军工程大学信息与导航学院,西安710077

出　　处：《火力与指挥控制》2019年第2期114-118,共5页Fire Control & Command Control

基　　金：国家自然科学基金(51377172);陕西省自然科学基础研究计划基金资助项目(2015JM5147)

摘　　要：传统超外差结构的接收机,主要通过Costas环实现DPSK信号的载波同步,而在零中频架构的接收机中,因为直接将射频信号下变频到基带,所以无法通过低通滤波器滤除与载波信号相乘的倍频分量。为完成零中频接收机中DPSK信号的载波同步,通过对零中频接收机接收到的信号进行分析,提出一种数学方式实现低通滤波,替代了传统Costas环路中的低通滤波器模块,Simulink仿真结果验证了该方案的可行性。最后根据设计方案,在FPGA硬件平台上实现零中频DPSK信号解调模块的设计,实验结果表明,这种方案可以满足零中频DPSK信号解调的需求。Intraditional superhetero dynestructure of the receiver,carrier synchronization is mainly accomplished by the Costas ring,but in zero-if structure receiver,high frequency signal is directly convert to baseband signal,it is hard to filter the frequency-doubling signal by the low-pass filter.In order to accomplish the carrier synchronization for DPSK signal demodulation in zero-if receiver,afteranalysing the signal received by zero-if receiver,this paper proposed a math method to filter the frequency-doubling signal,replace the low-filter in traditional structure of the Costas,the simulink simulation results of this new structure shows the feasibility of this scheme.Finally,accomplish the design of zero-if DPSK signal demodulation on FPGA platform,the experimental results verify this shceme can match the requirement of DPSK signal demodulation in zero-if receiver.

关 键 词：零中频 接收机 科斯塔斯环 DPSK解调 载波同步 位同步 

分 类 号：TN958.96[电子电信—信号与信息处理]