A transmitter comprising: - a modulator (201, 401) providing a phase-modulated constant-envelope radio-frequency signal; - a dividing unit (202, 402) for dividing a signal provided by said modulator into a first signal and a second signal which are identical to each other; - a first processing branch for processing a respective first signal provided by said dividing unit (202, 402), said first processing branch comprising a first phase shifter (203, 403) and a first power amplifier (204, 404) connected to each other in series; - a second processing branch for processing a respective second signal provided by said dividing unit (202, 402), said second processing branch comprising a second phase shifter (205, 405) and a second power amplifier (206, 406) connected to each other in series; - a combining unit (207, 407) for combining signals provided by said first and said second processing branches; - a first control arrangement (211-213, 411-416) for controlling an amplitude and an average power level of a signal output by said combining unit (207, 407) for higher power levels by controlling the amplifications applied by said first power amplifier (204, 404) and by said second power amplifier (206, 406) to said respective first and second signals, wherein said first control arrangement (211-213, 411-416) comprises a switching mode power supply (213, 413, 416), and is configured to control only said amplitude for lower power levels by controlling said amplifications based on a required amplitude modulation of said output signal, wherein said higher power levels are delimited from said lower power levels by an intermediate power level, wherein said intermediate power level is set to a value which corresponds to a lower limit of a range in which said switching mode power supply (213, 413, 416) and said first and second power amplifiers (204, 206, 404, 406) work linearly; and - a second control arrangement (222, 231, 422, 431-434) for controlling said average power level of said signal output by said combining unit (207, 407) at least for said lower power levels by controlling the phase shifts applied by said first phase shifter (203, 403) and by said second phase shifter (205, 405) to said respective first and second signals. - a modulator (201, 401) providing a phase-modulated constant-envelope radio-frequency signal; - a dividing unit (202, 402) for dividing a signal provided by said modulator into a first signal and a second signal which are identical to each other; - a first processing branch for processing a respective first signal provided by said dividing unit (202, 402), said first processing branch comprising a first phase shifter (203, 403) and a first power amplifier (204, 404) connected to each other in series; - a second processing branch for processing a respective second signal provided by said dividing unit (202, 402), said second processing branch comprising a second phase shifter (205, 405) and a second power amplifier (206, 406) connected to each other in series; - a combining unit (207, 407) for combining signals provided by said first and said second processing branches; - a first control arrangement (211-213, 411-416) for controlling an amplitude and an average power level of a signal output by said combining unit (207, 407) for higher power levels by controlling the amplifications applied by said first power amplifier (204, 404) and by said second power amplifier (206, 406) to said respective first and second signals, wherein said first control arrangement (211-213, 411-416) comprises a switching mode power supply (213, 413, 416), and is configured to control only said amplitude for lower power levels by controlling said amplifications based on a required amplitude modulation of said output signal, wherein said higher power levels are delimited from said lower power levels by an intermediate power level, wherein said intermediate power level is set to a value which corresponds to a lower limit of a range in which said switching mode power supply (213, 413, 416) and said first and second power amplifiers (204, 206, 404, 406) work linearly; and - a second control arrangement (222, 231, 422, 431-434) for controlling said average power level of said signal output by said combining unit (207, 407) at least for said lower power levels by controlling the phase shifts applied by said first phase shifter (203, 403) and by said second phase shifter (205, 405) to said respective first and second signals.