Linear modulators based on RF synthesis: realization and analysis

A technique for generating a gain and phase modulated high power radio signal is described using RF synthesis. The realization, which uses a unique twin VCO design, can give a theoretical near 100% amplifier efficiency with excellent linearity. A number of architectures are presented supported by both analytical and simulation results. Laboratory tests have verified the predicted performance for /spl pi//4 QPSK modulation.<
>