RESIDUAL PHASE NOISE MEASUREMENTS OF VHF, UHF, AND MICROWAVE COMPONENTS

The results of residual phase noise measurements on a number of VHF, U HF, and microwave amplifiers, both silicon (Si) bipolar junction trans istor (BJT) and gallium arsenide (GaAs) field effect transistor (FET) based, electronic phase shifters, frequency dividers and multipliers, etc., which are commonly used in a wide variety of frequency source an d synthesizer applications are presented. The measurement technique ha s also been used to evaluate feedback oscillator components, such as t he loop and buffer amplifiers, which can play important roles in deter mining an oscillator's output phase noise spectrum (often in very subt le ways). While some information has previously been published related to component residual phase noise properties, it generally focused on the flicker noise levels of the devices under test, for carrier offse t frequencies less than 10 kHz. The work reported herein makes use of an extremely low noise, 500 MHz surface acoustic wave resonator oscill ator (SAWRO) test source for residual phase noise measurements, both c lose-to-and far-from-the-carrier. Using this SAWRO-based test source a t 500 MHz, we have been able to achieve a measurement system phase noi se floor of -184 dBc/Hz, or better, for carrier offset frequencies gre ater than 10 kHz, and a system flicker phase noise floor of -150 dBc/H z, or better, at 1 Hz carrier offset. The paper discusses the results of detailed residual phase noise measurements performed on a number of components using this overall system configuration. Several interesti ng observations related to the residual phase noise properties of mode rate to high power RF amplifiers, i.e., amplifiers with 1 dB gain comp ression points in the range of +20 to +33 dBm, are highlighted.