Design of Frequency Characteristic Test Instrument Based on USB

Aiming at the issues of high cost, large size, high maintenance cost for traditional frequency characteristic test instrument, this paper introduces a design process of frequency characteristic test instrument based on USB2.0. The whole system took single clip microcomputer as the control core, and the sweep signal was produced by frequency synthesizer AD9850, so as to realize the measurement of network frequency characteristic. The measured data is transmitted via USB to PC for display, storage and playback. Finally, the feasibility and accuracy of scheme were verified through the experimental tests.