CAJ | 학술논문

传统的模拟式频率特性测试仪存在价格昂贵、条件苛刻、操作不便和性能指标易受温漂因素影响等不足。针对以上缺点，通过采用数字技术，将先进的 DDS 和 MSP430单片机相结合，集合一些常用的外围模拟电路，设计了一个简易的频率特性测试仪。系统对待测电路的输入信号及其输出响应采样，经数字信号处理后，获得电路的幅频特性和相频特性。设计的测试仪测某RLC网络，中心频率的相对误差小于0.2%，有载品质因数相对误差小于1.25%，最大电压增益大于-1 dB。频率特性测试仪输入输出阻抗均为50Ω，幅频误差绝对值小于0.5 dB，相频误差绝对值小于3°。测试仪能满足一般测试参数需求。
전통적모의식빈솔특성측시의존재개격앙귀、조건가각、조작불편화성능지표역수온표인소영향등불족。침대이상결점，통과채용수자기술，장선진적 DDS 화 MSP430단편궤상결합，집합일사상용적외위모의전로，설계료일개간역적빈솔특성측시의。계통대대측전로적수입신호급기수출향응채양，경수자신호처리후，획득전로적폭빈특성화상빈특성。설계적측시의측모RLC망락，중심빈솔적상대오차소우0.2%，유재품질인수상대오차소우1.25%，최대전압증익대우-1 dB。빈솔특성측시의수입수출조항균위50Ω，폭빈오차절대치소우0.5 dB，상빈오차절대치소우3°。측시의능만족일반측시삼수수구。
In view of the shortcomings of the traditional analog frequency characteristic tester,a simple frequency characteris-tic tester was designed by means of digital technology,and in combination with the advanced DDS,MSP430 microcontroller and some common peripheral analog circuits. The input signal and output response of the circuit under test are sampled by the sys-tem. The amplitude frequency and phase frequency characteristics of the circuit are obtained by digital signal processing. The de-signed tester was used to test A RLC network. The test results indicate that the system′s relative error of the center frequency is less than 0.2%,relative error of the loaded quality factor is less than 1.25%,maximum voltage gain is larger than -1 dB,input and output impedances are all 50 Ω,amplitude error absolute value is less than 0.5 dB,and phase frequency error absolute value is less than 3°. Tester can meet the testing requirements of general parameters.