C-Band Single-Chip Radar Front-End in AlGaN/GaN Technology

This paper presents the design and measurement results of a single-chip front-end monolithic microwave integrated circuit (MMIC), incorporating a high-power amplifier, transmit-receive switch, low-noise amplifier, and calibration coupler, realized in 0.25 μm AlGaN/GaN-on-SiC MMIC technology of UMS (GH25-10). The MMIC is operating in C-band (5.2-5.6 GHz) and is targeting the next generation spaceborne synthetic aperture radar. The use of GaN technology has resulted in a design that is robust against antenna load variation in transmit as well as against high received power levels, without the need for an additional limiter. By including a transmit-receive switch on the MMIC there is no need for an external circulator, resulting in a significant size and weight reduction of the transmit-receive module. The measured output power in transmit is higher than 40 W with 36% PAE. The receive gain is higher than 31 dB with better than 2.4 dB noise figure. To the best of the author's knowledge this is the first time such performance has been demonstrated for a single-chip implementation of a C-band transmit-receive front-end.