ULTRA-LOW-NOISE MICROWAVE-OSCILLATOR WITH ADVANCED PHASE NOISE SUPPRESSION SYSTEM

An advanced phase noise reduction technique has been developed to impr ove the short-term frequency stability of microwave oscillators, The t echnique is based upon an ultra-sensitive microwave frequency discrimi nator with effective noise temperature close to its physical temperatu re, The phase noise spectral density of a 9 GHz microwave loop oscilla tor incorporating such a discriminator has been measured as: -120 dBc/ Hz and -150 dBc/Hz at offset frequencies of 100 Hz and 1 kHz, respecti vely, This performance is at least 25 dB better than current state of the art, The developed phase noise reduction technique is quite genera l and can have valuable implications for the design of various ion; ph ase noise microwave oscillators.