Active Balun with Center-Tapped Inductor and Double-Balanced Gilbert Mixer for GNSS Applications

A new 1.575 GHz active balun with a classic double-balanced Gilbert mixer for global navigation satellite systems is proposed herein. simple, low-noise amplifier architecture used center-tapped inductor to generate differential signal equal in amplitude and shifted phase by 180°. The main advantage of the circuit that shift between outputs always 180°, an accuracy ±5°, gain difference does not change more than 1.5 dB. This are also preserved all process corners, as well temperature voltage supply variations. In design, band calibration system based on switchable capacitor bank proposed. were designed 110 nm CMOS process, consuming only 2.24 mA current from V supply. measured noise figure conversion were, respectively, NF = 7.7 dB GC 25.8 interest.