Low phase noise Ku band frequency multiplied and divided MMIC VCOs using InGaP/GaAs HBT technology

Abstract

A 36 GHz frequency multiplied VCO and a 1.9 GHz frequency divided VCO are presented. These are realized on an InGaP/GaAs HBT technology with low f/sub T/ and f/sub MAX/ of 30 GHz and 45 GHz, respectively. In a multiplied VCO, an LC-tuned VCO operates at 18 GHz, which is doubled in a frequency multiplier using the HBT's nonlinear characteristics. High conversion gain of about -2 dB is obtained in a small chip area, 0.56 /spl times/ 0.61 mm/sup 2/. Furthermore, high output power of -3 dBm is achieved with an SSB phase noise of -96.5 dBc/Hz at 1 MHz offset frequency from 36 GHz. The frequency divided VCO using a balanced VCO and a 1/8 static frequency divider using emitter-coupled logic is presented. It shows low phase noise performance of -115 dBc/Hz at 1 MHz offset from 15 GHz and - 130 dBc/Hz at 1 MHz offset from 1.9 GHz.