A low noise on-chip matched MMIC LNA of 0.76 dB noise figure at 5 GHz for high speed wireless LAN applications

A 2-stage PHEMT MMIC low noise amplifier of very low noise figure as low as 0.76 dB and gain over 16 dB at 5 GHz has been implemented using a minimum input matching network. The input network of the first stage was designed employing a small inductance of 0.89 nH to the gate of PHEMT series feedback amplifier whose gate width and series inductance were optimized for a simultaneous noise and VSWR match. We believe that the noise figure of 0.76 dB with 3 V operation in this work is the best result ever reported to date from MMIC LNAs around this frequency range, and is attributed to the minimized input matching network to the low noise PHEMT.