High-Spectral-Purity Microwave Oscillator: Design Using Conventional Air-Dielectric Cavity
A Sen Gupta, David A. Howe, Craig Nelson, Archita Hati, F L. Walls, J F. Garcia nava
We report exceptionally low PM and AM noise levels from a microwave oscillator that uses a conventional air-dielectric cavity resonator as a frequency discriminator. Our approach is to increase the discriminator's intrinsic signal-to-noise ratio by use of a high-power carrier signal to interrogate an optimally coupled cavity, while the high-level of the carrier is suppressed before the phase detector. We developed and tested an accurate model of the expected PM noise that indicates, among other things, that a conventional air-dielectric resonator of moderate Q will exhibit less discriminator noise in this approach than do more esoteric and expensive dielectric resonators tuned to a high-order, high-Q mode and driven at the dielectric's optimum power.
Sen Gupta, A.
, Howe, D.
, Nelson, C.
, Hati, A.
, Walls, F.
and Garcia nava, J.
High-Spectral-Purity Microwave Oscillator: Design Using Conventional Air-Dielectric Cavity, 2003 Joint Mtg. IEEE Intl. Freq. Cont. Symp. and EFTF Conf , Tampa, FL, US, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=105555
(Accessed December 2, 2023)