Cao Jia

A 30-dB 1–16-GHz low noise IF amplifier in 90-nm CMOS

This paper presents a high-gain wideband low-noise IF amplifier aimed for the ALMA front end sys- tem using 90-nm LP CMOS technology. A topology of three optimized cascading stages is proposed to achieve a flat and wideband gain. Incorporating an input inductor and a gate-inductive gain-peaking inductor, the active shunt feedback technique is employed to extend the matching bandwidth and optimize the noise figure. The circuit achieves a flat gain of 30.5 dB with 3 dB bandwidth of 1-16 GHz and a minimum noise figure of 3.76 dB. Under 1.2 V supply voltage, the proposed IF amplifier consumes 42 mW DC power. The chip die including pads takes up 0.53 mm 2 , while the active area is only 0.022 mm 2 .

A 60 GHz down-conversion mixer using a novel topology in 65 nm CMOS

A 60 GHz down-conversion mixer used in the unlicensed 60 GHz band system in 65-nm CMOS technology is presented in this paper. Based on the double-balanced Gilbert cell, the mixer comprises a cross-coupled pair to rise conversion gain and two series LCR network resonating at IF frequency to enhance bandwidth. As a result, both high gain and broad bandwidth are achieved. From the simulation results, the conversion gain exceeds 10 dB and 3-dB IF bandwidth is from 8 GHz to 16 GHz, the OP1dB is -6 dBm and noise figure is below 12 dB in band of interest. The mixer consumes 5 mA from a 1.2 V supply without buffer, and the chip area is 1×0.75 mm2 with pads.

A new wideband LNA using a gm-boosting technique

A new broadband low-noise amplifier (LNA) is proposed. The conventional common gate (CG) LNA exhibits a relatively high noise figure, so active gm-boosting technology is utilized to restrain the noise generated by the input transistors and reduce the noise figure. Theory, simulation and measurement are shown. An implemented prototype using 0.13 ?m CMOS technology is evaluated using on-wafer probing. S11 and S22 are below ?10 dB across 0.1?5 GHz. Measurements also show a gain of 18.3 dB with a 3 dB bandwidth from 100 MHz to 2.1 GHz and an IIP3 of ?7 dBm at 2 GHz. The measured noise figure is better than 2.5 dB below 2.1 GHz, is better than 4.5 dB below 5 GHz, and at 500 MHz, it gets its minimum value 1.8 dB. The LNA consumes 9 mA from 1.5 V supply and occupies an area of 0.04 mm2.

A 1–16 GHz wideband CMOS low-noise IF amplifier for ALMA radio astronomy receivers

This paper presents a wideband low noise IF amplifier developed for the ALMA Front End system using 90nm CMOS. A topology of shunt-series peaking and active shunt feedback low noise IF amplifier is proposed to extend the 3-dB and input matching bandwidth, combined with a series input inductor. The circuit achieves a flat gain of 34dB, while the 3-dB bandwidth as well as return loss of better than 10dB range from 1GHz to 16GHz. Operating at a 1.2V supply voltage, the IF amplifier consumes a dc power of 31.8 mW with a minimum noise figure of 4.2dB.