A GaN single chip front-end for C-band synthetic aperture radars

This paper describes a Gallium Nitride (GaN) Single Chip Front End (SCFE), operating in C-Band, for Synthetic Aperture Radar (SAR) applications. The design approach and the expected performances at both single functionality and overall chip level are provided. The SCFE is composed by a three stage high power amplifier (HPA), a single pole double throw switch (SPDT) and a three stage low noise amplifier (LNA). In receive mode, a small-signal gain around 36 dB with an associated Noise Figure of 2 dB @Tamb have been achieved. In transmit mode, 46.5 dBm of output power and 42% of power added efficiency are obtained at the antenna port reference plane. An isolation of 30 dB is achieved between the HPA input port and the LNA output port. The chip is optimized to work in 5.25 GHz–5.57 GHz operating band and occupies an area of 7×7 mm 2 .