Design of low-noise solid-state microwave sources

In applications such as communication and Doppler systems, the f.m. noise performance of microwave sources is quite critical. The noise performance of X-band microwave sources using transistorized crystal oscillators and amplifiers and varactor frequency multipliers has been studied. The paper discusses the limitations due to the crystal, the associated oscillator, the amplifier and the multiplier and also the methods used to measure their contribution. Theoretical and experimental results are compared.