2013年全国大学生电子设计竞赛简易频率特性测试仪（E题）【本科组】2013年9月7日摘要本系统以STC12C5A60S2为主控制器，该单片机是高速，低功耗，超强抗干扰的新一代8051单片机，速度快8-12倍。以自制DDS电路板AD9854为信号发生器，产生两路正交信号，观察输出波形，分析并改正信号输出模块的性能。然后将信号接入被测网络RLC串联谐振电路，经AD835构成的乘法器后，再经过低通滤波器，得到直流信号，返回单片机后经处理计算，从而得到被测网络的幅频和相频特性。关键词：STC12C5A60S2AD9854AD835AbstractThis system to STC12C5A60S2 as the main controller, the single chip microcomputer is a high-speed, low power consumption, strong anti-interference of a new generation of 8051 single chip microcomputer, 8-12 times faster. Signal generator using self-made DDS circuit board AD9854, resulting in two orthogonal signal, the output waveform is observed, analyzed and performance correction signal output module. The signal is then access the tested network RLC series resonant circuit, the AD835 multiplier, and low pass filter, get the DC signal, to the microprocessor after processing, which can be obtained by measuring the network the amplitude frequen