Abstract: Apparatus and a method for predistortion of a radio-frequency signal are described. At least one predistortion unit is described that is arranged to receive an analog baseband signal before amplification and to generate an analog predistortion signal based on said analog baseband signal. At least one mixer unit is also described and may be electrically coupled to the at least one predistortion unit. In this case, the at least one mixer unit is arranged to receive the analog baseband signal before amplification and the analog predistortion signal and to generate a weighted combination of said signals.

Abstract: An apparatus, which includes a local oscillator configured to oscillate at a carrier frequency and having output ports and configured to provide a signal of a respective phase at each of the output ports, wherein the respective phases are different from each other, a plurality of branches, each branch corresponds to one of the output ports and includes a mixer unit, where for each branch, the signal of the respective phase is applied to an input port of the mixer unit and the mixer unit is configured to modulate a baseband signal by the signal of the respective phase of the local oscillator to obtain, at its output port, a respective modulated signal and; a combiner configured to add the modulated signals from the branches to obtain a total signal to be output to a load; and at least one of the branches includes a multi-switch.

Abstract: Apparatus, methods and methods of manufacture are provided for the processing of a current mode signal. A first signal processing stage comprising at least one output terminal is configured to produce a current mode output signal. A mutual inductance stage is arranged to inductively couple the at least one output terminal of the first signal processing stage to at least one input terminal of a second signal processing stage, wherein an input signal is generated at the at least one input terminal of the second signal processing stage on the basis of the current mode output signal produced at the at least one output terminal of the first signal processing stage.

Abstract: Apparatus and a method for predistortion of a radio-frequency signal are described. At least one predistortion unit is described that is arranged to receive an analog baseband signal before amplification and to generate an analog predistortion signal based on said analog baseband signal. At least one mixer unit is also described and may be electrically coupled to the at least one predistortion unit. In this case, the at least one mixer unit is arranged to receive the analog baseband signal before amplification and the analog predistortion signal and to generate a weighted combination of said signals.