A 1–3 GHz CMOS mixer-first receiver frontend with dual-feedback OTA achieving 306 MHz IF bandwidth, 2.1 dB NF, and 33 dB gain
Abstract
In this paper, a mixer-first receiver frontend with dual-feedback baseband is proposed. The negative resistive and positive capacitive feedback paths are both applied to single-stage inverter-based operational transconductance amplifier (OTA) with fewer poles, to cover a wide BB frequency range. The N-path filtering at the RF side and second-order filtering at the BB side inhibit out-of-band blocker interferences. The receiver frontend is designed in 65 nm CMOS. Simulation results display an NF of 2.1 dB across 306 MHz IF bandwidth, and a maximum gain of 33 dB from 1 to 3 GHz LO frequency range. The in-band and out-of-band IIP3 are -13 and 16 dBm, respectively. The receiver core draws 40 mW at 1 GHz LO frequency.