A production oriented GaAs monolithic low noise amplifier for phased array radar systems

The design and performance of a two stage GaAs monolithic S-band low noise amplifier (LNA) is described. The design approach was aimed at realising a high performance, small size MMIC with good yields and low chip costs based around a 1 micron gate length MESFET IC technology. A negative feedback circuit topology was selected and optimised for minimum sensitivity to process batch variations, thus ensuring maximum yield. Practical results from the first production batches show that noise figures of less than 2.3 dB with more than 15 dB of associated gain have been realised simultaneously with input and output VSWRs of less than 2:1. These results are typical of the amplifier performances seen across several 2" wafer batches. However, noise figures as low as 2.0 dB have been measured