Title :
Improved interferometric method to measure near-carrier AM and PM noise
Author :
Rubiola, Enrico ; Giordano, Vincent ; Groslambert, Jacques
Author_Institution :
Politecnico di Torino, Italy
fDate :
4/1/1999 12:00:00 AM
Abstract :
An improved version of the interferometric method to measure near-carrier AM and PM noise is being presented. The main feature of this scheme is the capability to reduce the instrument noise by correlating the output of two equal interferometers built around the same device to be tested, thus enhancing the sensitivity. Two double interferometers are described, operating in the microwave and VHF bands. The latter shows a noise floor of -194 dB rad2/Hz when the signal power is +8 dBm. The sensitivity of both the instruments turns out to be significantly higher than the ratio of the thermal noise divided by the carrier power
Keywords :
amplitude modulation; electric noise measurement; microwave measurement; phase modulation; radiowave interferometry; AM noise; PM noise; VHF interferometry; double interferometer; microwave interferometry; near-carrier noise measurement; Instruments; Interferometers; Microwave devices; Noise measurement; Noise reduction; Phase noise; Power amplifiers; Temperature sensors; Testing; White noise;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
