High linearity 2nd IF CMOS mixer for DRM/DAB receiver

Abstract

An active CMOS mixer based on Gilbert cell was designed for the 2nd IF conversion in DRM/DAB receiver. Differential multiple gate transistors (DMGTR) combined with dynamic current injection technique was adopted to improve the noise and linearity performance respectively. The design was verified with SMIC0.18μm RF CMOS process. The simulated results show that the voltage conversation gain is 7.2dB and 7.12dB, the NF is 12.8dB and 12.28dB, the IIP3 is 18.05dBm and 19.62dBm for the DRM and DAB standards respectively. The power consumption is 5.9mW with a supply voltage of 1.8V. It exhibits a good compromise between the gain, noise and linearity for the 2nd IF mixer in DRM/DAB receivers.