Automatic measuring system for electronic noise and its performance

Most noise instruments can only provide noise figure or equivalent input noise at several frequency points or several fixed frequency bands. An automatic measuring system that can give not only equivalent input noise voltage and current power spectral density, but also noise performance, is presented. Because a low-noise preamplifier and the method of scanning sine signals for transfer function measurement are used, high accuracy of noise measurement is obtained. Noise measurement and data processing are done automatically by a personal computer