Linearity improvement for power MESFET devices using source inductive feedback and input impedance mismatch

Linearity can be improved drastically by sacrificing power gain with the same output power. GaAs MESFET devices with source-via-hole ground and with source-bond-wire ground are used to investigate the effect of source inductive feedback and input impedance mismatch on the effect of linearity. The output matching for all the devices are tuned for the maximum power condition. At 2.4 GHz, the device without source-bond-wire ground and input impedance mismatched has the highest linearity, OIP₃=50 dBm. gain=13.5 dB gain and P_1dB=29 dBm while the device with source-via-hole ground and input impedance matched has the lowest linearity OIP₃=40 dBm, 18.3 dB gain and P_1dB=29 dBm.