基于MSP432E401Y的信号失真度测量系统

Signal distortion measurement system based on msp432e401y

信号的总谐波失真度(THD)是衡量放大器性能的重要指标,本文设计了一种针对低频信号的总谐波失真度测量系统,能够对输入的周期信号进行采集分析,并测得输入信号的总谐波失真THD。本系统的硬件主要由放大电路系统和MSP-EXP432E401Y主控芯片构成,外接ESP32通讯模块与Android studio制作的手机app进行交互。周期输入信号首先通过AD603增益可控制放大器放大,随后接入加法电路滤去负压,然后由MSP432板载AD模块采入信号并进行数据处理,最后经由串口屏进行本地显示。本系统的软件设计是基于MSP432的FFT,处理得到输入信号的基波幅值及二至五次谐波幅值,通过ESP32将计算结果上传至服务器,手机端从服务器上下载数据。

This paper designs a system for measuring the total harmonic distortion(THD)of low frequency signals,which is able to collect and analyse the periodic signals and measure the THD of the input signals.The ESP32 communication module interacts with the mobile app created by Android studio.The cyclic input signal is first amplified by the AD603 gain-controlled amplifier,then filtered by the addition circuit to remove the negative voltage,then the signal is picked up by the MSP432 on-board AD module and processed for data processing,and finally displayed locally via the serial screen.The software design of the system is based on the FFT of the MSP432,processing to obtain the fundamental amplitude and second to fifth harmonic amplitude of the input signal,uploading the calculation results to the server via the ESP32,and downloading the data from the server on the mobile phone side.