Extending the range and accuracy of phase noise measurements

Recent progress in extending high-accuracy measurements of phase noise in oscillators and other devices are described for carrier frequencies from the RF to the millimeter region and Fourier frequencies up to 10% of the carrier (or a maximum of about 1 GHz). A brief survey of traditional precision techniques for measuring phase noise is included as a basis for comparing relative performance and limitations. Several calibration techniques are developed which, when combined with two previous oscillator techniques, permit one to calibrate all factors affecting the measurements of phase noise of oscillator pairs to an accuracy which typically exceeds 1 dB and in favorable cases can approach 0.4 dB