A 0.5–5.5 GHz low even-order distortion CMOS current-reused front-end for wideband RF receivers

This work presents a novel RF current-reused front-end with noise cancellation LNA and current-commutating mixer using 0.18 μm CMOS technology. The proposed design is applicable to a wideband receiver that converts a 0.5 - 5.5 GHz RF signal into a zero- or low-IF signal. A fully differential topology is adopted to suppress the even-order nonlinearity and common-mode noise. Additionally, the proposed approach incorporates capacitor cross-coupled common-gate (CCC-CG) and current-reused schemes to achieve low noise, input matching and power saving. Measurement results indicate a S₁₁ value lower than -10 dB, a noise figure of 3.1 - 3.6 dB, a conversion gain of 16.5 - 19.2 dB, an IIP₃ of -4.9 - -2.4 dBm, and an IIP₂ of 50 - 55.5 dBm over the entire RF bandwidth. While consuming 10.2 mA from a supply voltage of 1.8 V, the chip circuitry in the proposed method is especially attractive for its wideband low even-order distortion.