Noise spectrum of the 140-GHz gyrotron designed for controlled thermonuclear fusion installations

摘要

A method for measurement of gyrotron amplitude noise using the Mach-Zehnder interferometer as a rejection filter, the measurement facility, and results of testing a 140-GHz industrial high-power gyrotron are discussed. The method improved the sensitivity by two orders of magnitude over that of the direct detection method. The experimental relative power spectral density in a frequency range of 50-250 MHz from the line center is 7 x 10(-20)-5 x 10(-19) 1/Hz.