S-Band EXR Front-End Multifunctional GaAs MMIC

Abstract

A variable-gain low noise amplifier MMIC for an S-band AESA receiver front-end has been designed. The amplifier offers maximally 20 dB of gain and a noise figure of 1.3 dB, with 27 dB dynamic gain range. By integrating a power limiter, the circuit can withstand incoming signals (CW) of 32 dBm of power. All functionality has been integrated on a GaAs single chip, designed for a 4x4 QFN package. As such, the system replaces three to four off-the-shelf MMIC components. The MMIC is designed to operate at a single +5 V supply voltage. To reduce power consumption, a current reuse scheme not priorly used at SAAB Microwave Systems was adopted. A feauture of the employed gain control design is that for a given gain, the system can be set to prioritize either low noise or low intermodulation. To guarantee reliability, the system has been designed to maintain satisfactory performance due to both process and temperature variations.