基于单片机的数字信号传输性能分析仪的设计

本设计由数字信号发生及伪随机信号发生模块、低通滤波电路、数字信号分析电路等模块构成,通过MSP430单片机及DDS电路产生数字信号,由10M的有源晶振和移位寄存器产生伪随机信号。通过三个截止频率不同的低通滤波器对数字信号进行模拟干扰。伪随机信号发生器输出信号V3的幅度在100mV～TTL内可调。数字信号采用曼彻斯特编码,使其在分析电路中可以在很低的信噪比下从V2a中提取同步时钟信号,利用所提取的同步时钟信号作为示波器的触发脉冲,在示波器上显示出眼图,通过眼图幅度分析数字信号的传输性能。

Digital Signal Transmission Performance Analyzer Design with SCM

This design by digital signal happen and pseudo--random signal producing module, low pass filter circuit, digital signal analysis circuit module, through the MSP430 microcontroller and create a digital signal, DDS circuit by 10 M active crystals and shift register produce pseudo--random signak Through the three cut--off frequency of different low pass filter to simulate digital signal interference. Pseudo random signal generator output signal amplitude of the V3 in the adjustable within 100 mV - TTL. Digital signal the Manchester, in the coding analysis can be very low in the circuit the signal-to- noise ratio of the extracted from the V2a synchronous clock signal, the use of the extraction of synchronous clock signal transmission signal in the oscilloscope trigger showed on the eye chart, through the eyes of digital signal amplitude analysis transmission performance.