A Low-Noise 2.5GHz Direct-Conversion Receiver Frond-End with Low-Distortion Baseband Filters

A 2.5GHz direct conversion receiver front-end has a 3.2dB DSB NF, -14dBm IIP3, and +27dBm IIP2, referred to the LNA input. The RFI/Q mixers are configured as Gm-cells interfacing to current-mode CMOS I/Q continuous-time Elliptic filters. The filters can operate from a 1V supply and achieve an average input noise current of 11.2 pA/sqrt(Hz), <3% tuning accuracy and <0.5% I/Q bandwidth matching. The receiver draws 30mA from a 2.7V supply. The chip is fabricated in a 0.5&#x003BC;m 46GHzf_T BiCMOS process. The active area is 2.54 mm².