Design, analysis and characterization of active HBT down conversion RF mixer for WLAN applications

Abstract

This paper reports Si-Ge Hetro-junction Bipolar Transistor (HBT) BFP840FESD based active mixer for WLAN application with 70 MHz IF. The proposed design provides conversion gain around 10 dB, isolation around 30 dB, 1 dB gain compression point is around −7dBm, noise figure around 8 dB at operating frequency 2.4 GHz. Also a study of conversion gain variation with respect to various mixer parameters has been done in this work. The CAD based design and simulation is done using Advance design System (ADS). Verification of the design has been done through realizing hardware prototype on FR4 substrate. Measurement of fabricated prototype has been performed using Keysight Field-Fox spectrum analyzer N9918A. Simulated and measured results are in good agreement for the proposed work.