A signal processing circuit for providing a modulated analog transmit signal on the basis of a digital transmit data signal is disclosed. The signal processing circuit includes one or more digital circuit components and one or more analog circuit components, and is configured to vary a bias voltage or a supply voltage of at least one of the one or more digital circuit components or at least one of the one or more analog circuit components in dependence on a detected or predefined parameter when providing the modulated analog transmit signal. The detected or predefined parameter includes a parametric or environmental condition associated with the signal processing circuit.