A Reconfigurable Low-Voltage and Low-Power Millimeter-Wave Dual-Band Mixer in 65-nm CMOS

Abstract

In this paper, we propose, investigate, and demonstrate a reconfigurable low-voltage and low-power millimeter-wave mixer in a 65-nm CMOS, which can be switched as either a subharmonic mixer (SHM) or a fundamental mixer (FM) for the dual-band applications. Based on a modified Gilbert mixer topology, the proposed CMOS mixer can operate at a low supply voltage and low local oscillator (LO) pumping power while providing good performance in both SHM and FM modes. To the best of our knowledge, this is the first reported Gilbert SHM based on the stacked switching quads in a low-voltage CMOS technology. Under 1-V supply voltage and −3-dBm LO pumping power, the measured conversion gain (CG) of the proposed CMOS mixer is −4.8 ± 1.5 dB from 34 to 56 GHz and −0.1 ± 1.5 dB from 17 to 43 GHz in the SHM and FM modes, respectively. The measured double-sideband (DSB) noise figure (NF) is 18.5-20 dB from 37 to 49 GHz and 12.4-14 dB from 17 to 35 GHz in the SHM and FM modes, respectively. The measured input third-order intercept point (IIP3) is 2.9 and 3.4 dBm, respectively, for the SHM and FM modes at the LO frequency of 22 GHz. In addition, the total dc power consumption of the proposed mixer including output buffers is 7 mW in both the operation modes.INDEX TERMS CMOS, dual-band mixer, fundamental mixer (FM), Gilbert mixer, low-power, low-voltage, millimeter-wave (mmW), reconfigurable, subharmonic mixer (SHM).

A millimeter-wave fundamental and subharmonic hybrid CMOS mixer for dual-band applications

“…The maximum CG of the mixer is −13.7 and −7.6 dB for the SHM and FM modes, respectively, the 3-dB RF bandwidth is from 30 to 53 GHz and 16 to 35 GHz for the SHM and FM modes, respectively. The measured CGs of this mixer are considerably lower than that in [15], due to the following reasons: (1) the lack of IF buffers, which provide about 7-dB power gain in [15]; (2) the transconductance (g m ) of the transistors is lower than that in [15] due to V DS = 0 V;…”

“…The values of C F 1 , C F 2 , L F 1 , and L F 2 are chosen to make the cutoff frequency of the low-pass filter (LPF) higher than the IF frequency ( f IF ), whereas the values of C B 1 and C B 2 need to be small enough to block the IF signal in path 2. Three Marchand baluns are used to generate differential RF and LO signals [15, 23]. A 90° coupler and an inductor ( L C ) are jointly used to provide an optimum LO phase distribution for the switching quads.…”

“…By either mixing the input signal with the fundamental or higher-order harmonic component of the LO, dual-band performance can also be achieved [12, 13]. The mixers, which can be reconfigured between fundamental and subharmonic modes by changing the LO waveforms [14] or the bias conditions [15], have also been proposed for dual-band operation. In addition, an MMW dual-band switchable star mixer was also proposed by changing the effective length of the Marchand baluns [16].…”

Millimeter-wave dual-mode and dual-band switchable Gilbert up-conversion mixer in 65-nm CMOS process

“…The two stacked switching quads are driven by two quadrature LO signals, i.e. LOI and LOQ, respectively, which are generated by a 90° coupler and two Marchand baluns [11, 12]. By adding four bypass capacitors ( C 4 – C 7 ), the LO baluns could provide dc bias voltages ( V A and V G3 ) for the top and bottom switching quads without affecting the LO characteristics.…”

“…However, the passive mixers suffer from high conversion loss and require high LO pumping power, especially in complementary metal oxide semiconductor (CMOS) technologies. An MMW dual-band CMOS down-conversion mixer with a modified Gilbert topology was demonstrated in [11], but the balun-based input stage is not suitable for an up-conversion mixer and the conversion gain is still unsatisfactory.…”