A Full W-Band InP LNA With Enhanced Gain Flatness

This brief presents a full W-band low noise amplifier (LNA) based on Indium Phosphide (InP) high electron mobility transistor (HEMT) technology. It utilizes a four-stage common source structure, and source inductances of different stages are designed carefully to achieve bandwidth extension and lower noise figure (NF). To realize enhanced gain flatness during the full W band, the four stages are designed with different gain peaking frequencies. From 75 to 110 GHz, the measured gain is 22.5-24.6 dB with gain variation of less than 2.1 dB, and the measured NF is 2-3.4 dB. The measured P_1dB are -21, -21, and -20 dBm at 80, 92 and 105 GHz, respectively.