NOISE NEAR THE CARRIER IN MICROWAVE OSCILLATORS
CORNELL UNIV ITHACA NY
Pagination or Media Count:
This study of noise near the carrier in microwave oscillators was primarily an experimental survey of typical tubes. The noise in the oscillators output was detected as equivalent modulation by a receiver similar to those used in noise-measuring test sets available commercially. The signals of interest were fed into a spectrum analyzer which resolved them into self- and cross-spectra, the frequency range from 14 cs to 34 kcs being resolved into 25 bands of about 12 octave each. The cross spectra were derived from measurements of the self-spectra of linear combinations of the signals, with wide-band phase shifters having been used to permit observation of the imaginary components of the cross spectra. It was found that amplitude noise inutputs of the oscillators tested VA203, V217, VA161, QK610, 357H was too small to be observable with a receiver of this type, and that internally generated low-frequency beam-current fluctuations were not significant in producing frequency noise. The frequency-noise spectra observed were consistent with spectra that might be expected from theory, if independent ions were assumed in the interaction region.
- Radiofrequency Wave Propagation