Use of Active Diode Converter for Linearizing of Characteristics of Microwave Generator with Wideband Tuning of Frequency

This article deals with the use of active diode converters as converters for the linearization of the characteristics of a voltage controlled microwave oscillator (VCO) with broadband frequency tuning. It is shown that if the tuning range is completely preserved, the coefficient of the differential nonlinearity of the tuning characteristic can be significantly reduced. For VCOs with an octave tuning range and a 1 GHz/V tuning slope, it was possible to reduce the differential nonlinearity coefficient of the tuning characteristic from 6,2 to 1,19. The attention is paid to the additional phase noise of the VCOs, which arise due to the use of active diode converters. It is shown that when using low-noise Schottky diodes HSMS-281x and a low-noise amplifier such as AD8597, the level of additional phase noise can be less than -5 dB/Hz at 10 Hz frequency offset from the carrier and not more than -100 dB/Hz at 100 kHz frequency offset.