Push-Push X Band GaInP/GaAs VCO With a Fully Monolithic Microstrip Resonator

In this paper the design of a VCO using GaInP/GaAs HBT technology is presented. The VCO is designed to be a part of a PDH point to point radio system. To achieve low phase noise performances GaInP/GaAs HBT technology and push-push topology have been chosen. The MMIC includes predistorters to emphasize the second harmonic, f/sub 0//2 prescalers for PLL locking and buffer amplifiers. A fully monolithic microstrip resonator is coupled with integrated varactors to achieve the specified tuning bandwidth. Phase noise, bandwidth and power measurements will also be presented.