基于FPGA与DDS的频率特性测试仪的设计  

Design of frequency characteristic tester based on FPGA and DDS

作　　者：张强 崔永俊 ZHANG Qiang;CUI Yongjun(Key Laboratory of Instrumentation Science&Dynamic Measurement,Ministry of Education,School of Instrument and Electronics,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学仪器与电子学院仪器科学与动态测试教育部重点实验室,山西太原030051

出　　处：《电子设计工程》2021年第7期129-133,共5页Electronic Design Engineering

摘　　要：为了更好地对被测电路的幅频特性与相频特性进行测量,提出一种基于DDS技术与FPGA设计的频率特性测试仪。该测试仪以FPGA为控制与数据处理的核心,由高性能的DDS技术产生信号,以AD8302来检测频率相位增益,测量了1-90 MHz带宽的频谱特性,有点测与扫频测量两种选择。将测量结果与Matlab仿真的结果进行对照,结果高度吻合;与点测法的测量结果对比,幅频特性测量误差的绝对值小于0.5 dB,相位测量误差不大于3°,且基本实现了测试仪的全数字化、小型化、功耗低、本身操作简便、准确度高、稳定性强,且频率测量范围宽广。In order to better measure the amplitude frequency characteristics and phase frequency characteristics of the circuit under test,a frequency characteristic tester based on DDS and FPGA is proposed.The instrument takes FPGA as the core of control and data processing,uses high⁃performance DDS technology to generate signals,uses AD8302 to detect the phase gain,and realizes the spectrum characteristics of measuring 1 to 90 MHz bandwidth.There are two options:point measurement and sweep frequency measurement.The measurement results are highly consistent with the simulation results.The amplitude⁃frequency characteristic measurement error is less than 0.5 dB,and the phase error is less than or equal to 3°.Moreover,it is basically fully digitized,miniaturized,low power consumption,simple operation,high accuracy,compact and portable,and wide measuring range.

关 键 词：频率特性测试仪 FPGA DDS 频率特性 AD9852 

分 类 号：TN711.1[电子电信—电路与系统]