Highly robust X-band quasi circulator-integrated low-noise amplifier for high survivability of radio frequency front-end systems

Abstract

In this brief, an X-band quasi circulator (QC)-integrated low-noise amplifier (LNA) implemented in 65-nm Complementary Metal Oxide Semiconductor (CMOS) technology is presented. This work is the first QC-LNA for the X-band to the author's best knowledge, which achieves 30-dB flat gain in 8–12 GHz with only 0.5-dB variation across the band. This QC-LNA uses two-stage current reused techniques with variable impedance load. QC provides the minimum insertion loss of 0.9 dB with good return and isolation losses. Statistical analysis is presented for QC-LNA to predict the percentage error tolerance. Quasi-Newton (QN) control algorithm is used to optimize the parameter of the whole design. The design of experiment (DoE) is performed to claim the contribution towards gain, return loss, and noise figure. The proposed LNA measurement provides a minimum NF of 1 dB at 9.5 GHz, which remains less than 1.4 dB across 8–12 GHz. The fabricated LNA works with a supply voltage of 1.2 V and is unconditionally stable across the frequency. The calculated chip area is 0.84 × 0.52 mm2. This QC-LNA exhibits an input and output 1-dB compression point (IP1dB and OP1dB) of −15 and +13.8 dBm, respectively. It also exhibits third-order input and output intercept point (IIP3 and OIP3) of +10 dBm and of +40 dBm, respectively. The proposed QC-LNA draws only 8.7 mA from 1.2 V. © 2021 John Wiley & Sons, Ltd.