GaAs Monolithic Astable Multivibrator Type VCO Operable up to KU Band

The estimated theoretical limit to oscillation frequency predicts that the frequency of a GaAs monolithic astable multiviblator type oscillator can be increased from the maximum reported frequency of 5 GHz to 17 GHz by optimization of circuit parameters. The increase is made possible by the W-silicide self alignment process due to its precision processing and high uniformity of FETs within a wafer. This type of oscillator is suitable for use as the local oscillator in monolithic front ends because it can be coupled directly with a double balanced mixer or prescaler without any phase shift circuits. Its simultaneous production of 0° and 180° phase output has made it possible to fabricate the VCO and prescaler on one chip. The operation of this chip is confirmed up to 2 GHz which is the upper limit frequency of the prescaler.