Abstract: A digital polar modulator (DPM) for transforming a baseband signal into a modulated digital modulator output signal comprises an input unit and two low-pass delta-sigma modulators, a first one being connected downstream from the first input part and configured to provide at its output a first pulse train in dependence on an amplitude- modulating baseband signal component, and a second one being connected downstream from the second input part and configured to provide at its output a multilevel quantized signal in dependence on a phase modulating baseband signal component; a multiphase generator, which is configured to provide a set of square-wave carrier signals having a common carrier frequency and exhibiting discrete phase shifts with respect to each other; a multiplexer, which is configured to provide a multiplexer output signal that is formed by switching, in dependence on a signal received at a select input as a function of time, between selected ones of the carrier signals; and a combiner unit.

Abstract: A digital polar modulator (DPM) for transforming a baseband signal into a modulated digital modulator output signal comprises an input unit and two low-pass delta-sigma modulators, a first one being connected downstream from the first input part and configured to provide at its output a first pulse train in dependence on an amplitude- modulating baseband signal component, and a second one being connected downstream from the second input part and configured to provide at its output a multilevel quantized signal in dependence on a phase modulating baseband signal component; a multiphase generator, which is configured to provide a set of square-wave carrier signals having a common carrier frequency and exhibiting discrete phase shifts with respect to each other; a multiplexer, which is configured to provide a multiplexer output signal that is formed by switching, in dependence on a signal received at a select input as a function of time, between selected ones of the carrier signals; and a combiner unit.

Abstract: The invention concerns an electronic circuit comprising a sigma-delta modulator (200) and a clock generator (210) which outputs a clock signal (clk(t)) which is suitable for clock control of the sigma-delta modulator (200), wherein the clock generator is adapted to set the clock rate of the clock signal (clk(t)) variably in dependence on an instantaneous frequency of the input signal (x(t)).