Abstract: A transmitter for transmitting signals, comprising: a modulator for modulating a data signal, the modulator being capable of modulating the data signal according to any of two or more modulation schemes to form a modulated signal; an amplification arrangement for amplifying the modulated signal with any of two or more levels of gain; and a control system configured to interdependently select one of the modulation schemes and one of the levels of gain, and to control the modulator to adopt the selected modulation scheme and to control the amplifier to adopt the selected level of gain.