Title :
A 24 GHz Subharmonic Direct Conversion Receiver in 65 nm CMOS
Author :
Mazzanti, Andrea ; Sosio, Marco ; Repossi, Matteo ; Svelto, Francesco
Author_Institution :
Dipt. di Elettron., Univ. di Pavia, Pavia, Italy
Abstract :
Scaled CMOS proves to be suitable for the design of transceiver ICs at micro- and millimeter-waves. The effort is presently toward compact and low-power solutions in view of integrating several transceivers on the same chip enabling phased array systems. In this paper we present a 24 GHz receiver, based on a subharmonic direct conversion architecture, designed in a 65 nm node. The local oscillator takes advantage of the half frequency operation proving significantly lower power consumption when compared to conventional solutions running at received frequency. Stacked switches for subharmonic down-conversion are passive to save voltage room, current driven and loaded by a transresistance amplifier. Optimum biasing of the switches allows maximizing linearity while saving power in the baseband. The integrated LNA matching network is the bottleneck toward low sensitivities. The LNA design trades-off power consumption, gain and sensitivity. Detailed insights into implementation issues, critical in a single-ended topology where both forward and return signal paths have to be supported, are provided. The chip consumes 78 mW and occupies 1.4 mm2 of active area. Experiments show: 30.5 dB gain, 6.7 dB NF, -13 dBm IIP3.
Keywords :
CMOS integrated circuits; low-power electronics; microwave switches; millimetre wave oscillators; millimetre wave receivers; transceivers; forward signal paths; frequency 24 GHz; gain; gain 30.5 dB; gain 6.7 dB; half frequency operation; integrated LNA matching network; local oscillator; microwaves; millimeter waves; optimum biasing; phased array systems; power 78 mW; power consumption; return signal paths; scaled CMOS; sensitivity; single-ended topology; stacked switches; subharmonic direct conversion receiver; subharmonic down-conversion; transceiver IC; transceivers; transresistance amplifier; CMOS integrated circuits; Capacitors; Impedance matching; Inductors; Mixers; Noise; Receivers; CMOS; LNA; integrated circuits; millimeter waves; receivers; subharmonic mixers;
Journal_Title :
Circuits and Systems I: Regular Papers, IEEE Transactions on
DOI :
10.1109/TCSI.2010.2071711