Validating Predistortion Methods using a Flexible Hardware Testbed

In this work, a hardware testbed is proposed to validate predistortion schemes designed to compensate for imperfections in a satellite channel. Such imperfection arise due to the nonlinear power amplifier and output channel filter and it is crucial to verify predistortion methods using satellite hardware. The testbed can be used to research novel state-of-the-art algorithms or for acceptance testing of existing algorithms prior to satellite launch. Using the custom-build testbed, various predistortion schemes were compared for a realistic setup consisting of an X-band travelling-wave tube amplifier and output channel filter. An improvement in SNR of 8 dB at the receiver was demonstrated using a Wiener predistortion system.