13 mW 80 GHz down‐conversion mixer with 1.5 dB gain and 49.2 dB LO–RF isolation

Abstract

An 80 GHz double-balanced down-conversion mixer for automotive radars using standard 90 nm complementary metal oxide semiconductor (CMOS) technology is reported. The mixer comprises a double-balanced Gilbert cell with inductive source-degeneration radio-frequency (RF) transconductance stage for wideband RF-port input impedance matching and conversion gain (CG) enhancement, a Marchand balun for converting the single RF input signal to differential signal, a Marchand balun for converting the single local oscillator (LO) input signal to differential signal and a baseband amplifier. The mixer consumes 13 mW and achieves excellent RF-port input reflection coefficient of −13.1 ∼ −19.4 dB and LO-port input reflection coefficient of −9.1 ∼ −11.8 dB for frequencies in the range 75-85 GHz. In addition, for frequencies of 75-85 GHz, the mixer achieves CG of −1 ∼1.5 dB, LO-RF isolation of 43.5-49.2 dB and LO-intermediate frequency (IF) isolation of 56.5-64.5 dB, one of the best CG and port-to-port isolation results ever reported for a CMOS down-conversion mixer with operation frequency about 80 GHz.

A 77-GHz Down-Conversion Mixer with +18.4 dB High Gain, +12.2 dBm OIP3, and Low Noise in 90-nm CMOS Technology

“…Comparing with the 76-77 GHz CMOS mixer in [9], the proposed mixer shows better CG, larger port-to-port isolation, and larger FOM value. The proposed mixer consumes less power than the mixers described in [9], [14], and [15]. In comparison to the mixer described in [16], the proposed mixer offers better noise performance.…”

“…9 Table 2 summarizes the performance of the proposed down-conversion mixer and compares the parameters with the recently reported mixers. Due to the application of an improved gain-boosting approach, the proposed mixer exhibits a signi cant enhancement in CG and the noise compared with the mixers published in [13], [14]. Comparing with the 76-77 GHz CMOS mixer in [9], the proposed mixer shows better CG, larger port-to-port isolation, and larger FOM value.…”

A 76–81 GHz CMOS mmW quadrature down-conversion mixer for automotive radar applications

“…Besides, the mixer should provide some gain to suppress noise contributions from successive building blocks, such as basedband amplifiers and ADC. How to realize a high linearity, high gain and low noise mmW mixer has become a research hotspot [15,16,17,18,19,20,21,22,23,24,25].…”