A 4-31GHz Direct-Conversion Receiver Employing Frequency-Translated Feedback

This paper presents a multi-band direct-conversion receiver with frequency-translated feedback. The forward path includes a low-noise transconductance amplifier followed by four-phase passive mixers which drive baseband amplifiers, and the feedback path employs tunable resistor banks attached to additional four-phase passive mixers, allowing tunable frequency-selective input matching. The receiver operates from 4-31 GHz exhibiting greater than 25 dB gain through 22 GHz and greater than 17 dB gain through 31 GHz. Noise figure is 5.2 to 9.8 dB, rising with frequency; input-referred 1-dB compression point is -17 dBm; and in-band IIP3 is -6.6 dBm. Out-of-band 1-dB blocker compression is greater than -12 dBm. The receiver core consumes 91 mW, whereas an integrated 2:1 frequency divider and pass-gate buffer for generating non-overlapping four-phase clocks consumes an additional 87-227 mW from 4-31 GHz, respectively.