High Efficiency Power Amplifier Architectures for RF Applications

A switch-mode power amplifier system comprising:

• a signal encoder comprising a delta sigma modulator;
• a switch-mode power amplifier;
• a reconstruction filter;
• wherein the delta sigma modulator comprises:
• a signal demultiplexer configured to receive an input signal and to demultiplex the input signal into a plurality of streams of symbols at symbol boundaries;
• a plurality of delta sigma modulators, where each delta sigma modulator is configured to receive a stream of symbols from the plurality of streams of symbols and to generate a delta sigma modulated output;
• and
• a signal multiplexer configured to receive a plurality of delta sigma modulated outputs from the plurality of delta sigma modulators and to multiplex together the plurality of delta sigma modulated outputs into a pulse train.