Modeling of efficiency UHF class-D power amplifier with bandpass sigma-delta modulation

Abstract

Sigma-delta modulation is a method of constructing the radio frequency linear power amplifier with the using non-linear components. It can significantly simplify the structure of the power amplification path, which in this case shall operate as one-bit DACs. The preliminary modeling of potential different variants of the output stage in classes E, F, D (voltage switching and current switching) and the pulsed gate modulation was done. It is shown that the required linearity of amplitude characteristic can be realized only in the class D amplifier with voltage switching. Such an amplifier can be constructed in a bridge or half-bridge circuits.