Patent ID: 7269232

Claim:
A device for producing a phase and amplitude modulated radiofrequency output signal suitable for radio transmission, comprising: at least one data input for receiving a digital message containing data to be transmitted; composite means of coding for generating, on the basis of said digital message, a first string of digital values corresponding to a phase modulation component of the output signal and a second string of digital values corresponding to an amplitude modulation component of the output signal; means for generating a phase control signal and an amplitude control signal on the basis of said first and second strings of digital values, phase modulation means, having an input and an output, said input receiving the phase control signal and said output delivering a radiofrequency signal of substantially constant amplitude and phase modulated as a function of the phase control signal; and a variable-gain radiofrequency power amplifier, having an input, a gain control input and an output, said input being coupled to the output of the phase modulation means so as to receive said phase modulated radiofrequency signal of substantially constant amplitude, said gain control input receiving the amplitude control signal, and said output delivering the output signal, wherein said means for generating comprise means of temporal clamping of said phase control signal and of the amplitude control signal so as to synchronize the phase modulation component with the amplitude modulation component in the output signal, and wherein said means of temporal clamping are designed to carry out a temporal clamping of the phase control signal and of the amplitude control signal as a function of a baseband signal which is obtained on the basis of the output signal.