A 1024-Element Ku-Band SATCOM Dual-Polarized Receiver With >10-dB/K G/T and Embedded Transmit Rejection Filter

Abstract

This article presents a 1024-element dual-polarized Ku-band (10.7-12.7 GHz) satellite communication (SATCOM) receive (RX) phased array. The array consists of four 16 ×16 subarray tiles, each of which comprises 64 eight-channel beamformer chips, 256 dual-channel low-noise amplifiers (LNAs), and 256 dual-polarized antennas built on an affordable printed circuit board (PCB). The antennas spaced at λ/2 spacing at 12.2 GHz in an equilateral triangular grid allow scanning up to x±70° in all planes while maintaining a cross-polarization level $ <; -30$ dB. The use of LNAs just after the antennas enables a low-noise operation with an antenna gain-to-noise temperature (G/T) of 10.5 dB/K ( T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ant</sub> = 20 K) at broadside while maintaining a directivity of 34 dB at 11.7 GHz. Also, a two-pole/two-zero filter is placed between the LNA and the beamformer chip to greatly attenuate any transmit leakage signal at 14-14.5 GHz. The lightweight, low-cost PCB with all silicon chips and a thickness of 3.4 mm presents a viable candidate for Ku-band SATCOM ground and Satcom-On-The-Move (SOTM) terminals.