A Very Flat Variable Gain Amplifier MMIC for C-Band Satellite Receiver

This paper describes the design, the realization, and the performance of two versions of an analog C-band GaAs variable gain amplifier module suitable to application in C-band satellite receiver. This modules uses the ability of the Dual-Gate MESFET to provide variable gain. The highest obtained dynamic control range is 30 dB with very flat gain response within 3-5 GHz frequency range. Input and output return losses are always better than 15 dB and the phase variation versus gain lower than 10 degrees over a 20 dB gain/attenuation range. Two wafers of both versions were processed by THOMSON/DAG GaAs foundry using a 0.5 ¿m gate length technology. The overall manufacturing RF-yields are 45% and 60% for the two versions presented.