A high 2LO-to-RF isolation GaInP/GaAs HBT sub-harmonic Gilbert mixer using three-level topology

Abstract

A 5.2 GHz three-level sub-harmonic downconversion Gilbert mixer using GaInP/GaAs HBT (Heterojunction Bipolar Transistor) technology is demonstrated in this paper. The LO frequency is half of the RF frequency for the three-level sub-harmonic mixer architecture; therefore, the RF frequency is 5.2004 GHz and LO frequency is 2.6 GHz. The conversion gain is 14.5 dB, IP(1dB') is -18 dBm, IIP(2) is 13 dBm and the IIP(3) is -5 dBm when the LO power equals to -8 dBm. The 2LO-to-RF leakage is about -83 dBm. The RF input return loss is better than -18 dB from DC to 6GHz.