A 2.77-dB NF K-Band Four-Element Dual-Beam Phased-Array Receiver With 39-dB Tx-Band Rejection for SATCOM Applications

This brief presents a K-band four-element dual-beam phased-array receiver in 65-nm CMOS SOI to enhance the Tx-band rejection for low-earth-orbit satellite communication (SATCOM) applications. By properly designing the inter-stage and output matching networks of the four-stage low-noise amplifier (LNA), the Tx-band rejection of the receiver can be effectively enhanced to fulfill the practical requirements of more than 35 dB. Meanwhile, considering the influence of the parasitic parameters of the LNA during practical design, the input matching network is properly designed to meet the impedance conditions of noise figure (NF) lower than 2.77 dB across the entire working frequency. Additionally, in response to the requirements for accurate phase shifts in phased-array systems, an active vector-modulated phase shifter is designed. Based on the proposed method, a K-band four-element dual-beam phased-array receiver operating from 17.7 to 21.2 GHz is designed and measured. The measurement results show the Tx-band rejection is greater than 39 dB, the single-channel gain is 21.48-25.31 dB, and the noise figure is 2.42-2.77 dB over the entire working frequency. Meanwhile, the measured root mean square (RMS) gain error and RMS phase error are less than 0.43 dB and 3.8°, respectively.

I. Introduction

Due to the intricate design and high cost of the conventional phased-array system, it is challenging to meet the low-cost and compact application requirements of low-earth-orbit (LEO) and high-throughput communication satellites. In recent years, with the development of silicon-based millimeter-wave IC technology, the T/R modules in phased-array systems have been gradually replaced by monolithic integrated silicon-based chips. Leveraging silicon technologies like CMOS and Bi-CMOS, the monolithic receiver can integrate low noise amplifiers (LNAs), phase shifters, attenuators, distribution networks and control circuits together on one chip, which makes the cost and area of the phased-array systems greatly reduced [1], [2], [3], [4], [5], [6], [7], [8], [9].