A method for reducing the RF power requirement in active load pull systems uses impedance tuners between the test transistor output and the output port of the active system. The active system is either a closed loop (active load) system or an open loop system using split or synchronized signal sources. The impedance tuners are wideband (fundamental) tuners, harmonic rejection tuners or multi-harmonic tuners. A 7:1 transforming ratio of the tuners yields a reduction of 11dB in power requirements from the active load or the synchronized source(s); a multi-harmonic tuner or a harmonic rejection tuner is used for independent harmonic tuning, in case of absence of a harmonic injection from the active load; a multi-harmonic tuner is used as a pre-matching section creating harmonic loads and reducing the power requirements from the harmonic injection sources as well.
Method for Reducing Power Requirements in Active L/P Systems / 8,497,689
Tuesday, July 30, 2013