TVTL Mixer-First Phased Array Receiver for Space Frequency Interference Rejection

This article proposes a modified architecture for a mixer-first phased array receiver, addressing the crucial need for high linearity and low noise in commercial wireless applications. Instead of using the conventional low-noise amplifier (LNA), a new time-variant transmission line (TVTL) mixer is implemented as the initial stage. The monolithic microwave integrated circuit (MMIC) TVTL chip’s performance exhibits a broadband conversion gain of up to 4.2 dB. Furthermore, it shows an input-referred P1dB of 12 dBm along with a low noise figure (NF) of 3 dB. Furthermore, a low-cost and low-power liquid crystal phase shifter (LCPS) is integrated into the LO path to minimize the impact of lossy phase shifters on the receiver’s NF. To validate the proposed architecture, a 1-D electronically steered phased array is designed, fabricated, and measured. The array utilizes a four-element patch antenna array, four TVTL chips as mixers, and four LCPSs. Measurement results show continuous beam scanning from 0° to 20° elevation angle, confirming the effectiveness of the proposed architecture in achieving enhanced linearity and tolerance to strong in-band and out-of-band interference/jamming.