A wideband low power merged balance-balun-LNA and I/Q-mixer

This paper presents a low power wideband RF receiver front-end in CMOS 180 nm technology that operates between 0.3 and 4.7 GHz. The mixer has a quadrature current commutating gilbert cell configuration that utilizes a novel broadband noise-canceling balanced balun-LNA as the transconductance stage. The noise-canceling balun LNA utilizes an additional noise-reduction technique that enhances its performance noticeably. Both of the common gate and common source stages of balun LNA are matched by employing equal-sized transistors that are biased with the same currents and load resistances. This technique results in superior symmetry, enhanced noise, and linearity performance under reduced power consumption. Post-layout simulation results show that the implemented balun LNA-I/Q-mixer has a conversion gain of 14.05 dB. The second and third-order intermodulation intercept points are +42.13 dBm and +4.13 dBm, respectively. The double-sideband NF is 4.74 dB. The proposed structure consumes only 6.7 mW from a 1.8 V supply and occupies a 0.056 mm(2) chip area.