High linearity MMIC amplifiers for on-board satellite S-DMB converters

This paper presents the design, simulation and measurement of two GaAs P-HEMT high linearity amplifiers for S-DMB applications, operating in the S and UHF bands. The amplifiers are part of a high linearity downconverter, so a specific topology and an active matching network have been chosen to achieve a high OIP3 value as well as good input and output return losses without using any external components. The S-band and UHF-band amplifiers exhibit an OIP3 of 23 dBm and 27 dBm respectively. They have also been measured included in a down-converter, achieving a total gain of 19 dB, an ouput P1dB of 10.5 dBm and a OIP3 of 31 dBm.