A GaN MMIC chipset suitable for integration in future X-band spaceborne radar T/R module Frontends

Abstract

A set of monolithic microwave integrated circuits (MMICs) has been successfully developed by using a qualified European GaN HEMT technology. In particular a high power amplifier (HPA), a low noise amplifier (LNA) and a single pole double throw (SPDT) switch have been designed, manufactured and tested. The presented chipset is very suitable for integration in future GaN-based T/R module Frontend for spaceborne X-band SAR applications. In particular, the MMIC HPA integrates two stages of gain in 5.5 × 4.0 mm2 of area. Its measured performance is an output power of 27 W, a PAE of 36% with a linear gain greater than 24 dB from 8.8 GHz to 10.2 GHz. The MMIC LNA integrates three stages of gain in 3.0 × 2.02 mm2 of area. Its measured performance is a small signal gain greater than 23 dB with an associated noise figure of 1.6 dB in the frequency range from 7.4 to 11.4 GHz. Besides, its output power at 1 dB of gain compression is greater than 22 dBm. The MMIC SPDT switch exploits a robust asymmetrical absorptive/reflective topology in 3.0 × 1.0 mm2 of area. The chosen topology allows obtaining different functionalities of each switched branch. In the frequency range from 8.4 GHz to 10.8 GHz its measured performance is an insertion loss lower than 1 dB for both tx and rx path, and tx-mode rx-mode isolations better than 20 dB and 28 dB respectively. Besides, the tx path 1 dB insertion loss compression occurs at nearly 20 W of input power.