A 1- to 10-GHz RF and Wideband IF Cross-Coupled Gilbert Mixer in 0.13- $\mu\hbox {m}$ CMOS

A modified Gilbert-cell mixer exhibiting both wideband radio-frequency (RF) and wideband IF performance is presented. With the proposed common-gate RF stage with the cross-coupled complementary transistors, a measured conversion gain of 3-8 dB over an RF band of 1-10 GHz is demonstrated, together with an RF input return loss better than 10 dB. The proposed mixer also incorporates wideband active local oscillator (LO) and IF baluns for matching and testing purposes. An IF bandwidth from 100 MHz to 1 GHz is achieved with a conversion gain variation of less than 2 dB. The measured output return loss within the IF band is better than 10 dB. Fabricated in a standard 0.13- μm CMOS technology, the chip only draws 7 mA from a 1.2-V supply due to the current reuse in the proposed RF stage. The measured input referred 1-dB compression point IP1-dB, third-order input intercept point IIP3, and single-sideband noise figure are better than -16 dBm, - 7 dBm, and 15 dB throughout the entire RF band.