利用高速DSP实现信号自主识别及数字解调  

Implementation of Independent Signal Recognition and Digital Demodulation by Using High-Speed DSP

作　　者：葛辛亮 GE Xinliang(Hangzhou Dianzi University Information Engineering College,Hangzhou 310018,China)

机构地区：[1]杭州电子科技大学电子信息学院,浙江杭州310018

出　　处：《现代信息科技》2023年第4期67-71,共5页Modern Information Technology

摘　　要：文章设计了一个可以测量并显示信号源输出的被测信号调制度等参数,自主识别并显示被测信号的调制方式(AM、FM、CW),输出解调信号的信号调制度测量装置。作品以TI C2000系列的F28379 DSP为主控制器,使用F28379内置的16 bit 1.1Msps SAR ADC在差分模式下进行信号采集。模拟前端包括DDS本振输出和混频器组成的超外差式接收系统,以及一级比较器、一级分频器和一级单端转差分的低失真差分ADC驱动器。解调方案汲取软件无线电的核心思想,综合使用希尔伯特变换、正交解调等方法,可以快速且精确地自主识别被测信号的调制方式,测量并显示调制度等参数,调幅度测量误差小于5‰,调频度和最大频偏测量误差小于2‰,且能输出解调信号波形。This paper designs a measured signal modulation device that can measure and display the signal modulation which is output by signal source and other parameters, independently identify and display the measured signal modulation mode(AM, FM, CW), and output the signal modulation measurement device. The work uses the F28379 DSP of the TI C2000 series as the main controller, uses 16bit 1.1 Msps SAR ADC built-in the F28379 for signal acquisition in differential modes. The analog front-end includes the superheterodyne reception system consisting of a DDS local vibration output and a mixer, as well as a low-distortion differential ADC drive with a first-level comparator, first-level frequency divider, and first-level single-end rotation differential. The demodulation scheme uses the core idea of software radio, uses Hilbert transform, quadrature demodulation and other methods synthetically. It can quickly and accurately identify the measured signal modulation mode independently, measure and display parameters such as modulation system. The measurement error of modulation amplitude is less than 5‰, modulation frequentness and maximum frequency deviation measurement error is less than 2‰,and it can output demodulation signal waveform.

关 键 词：DSP 自主识别 超外差式接收系统 希尔伯特变换 正交解调 

分 类 号：TP274[自动化与计算机技术—检测技术与自动化装置] TN99[自动化与计算机技术—控制科学与工程]