Patent ID: 7158582

Claim:
An I/Q modulator for processing a time-discrete I/Q signal comprising an I component and a Q component which is substantially orthogonal thereto, the I/Q signal being based on a sampling frequency which is equal to substantially four times a carrier frequency of a carrier signal onto which the I/O signal is to be modulated, said I/Q modulator comprising: a predistorter for predistorting the I component and the Q component with a predistortion signal which depends on the I component and the Q component and which comprises a first predistortion component and a second predistortion component, the predistorter being arranged for forming a predistorted I component as a difference between the I component multiplied by the first predistortion component and the Q component multiplied by the second predistortion component and for forming, in temporal alternation therewith, a predistorted Q component as a sum of the I component multiplied by the second predistortion component and of the Q component multiplied by the first predistortion component, so as to obtain a predistorted output signal; and an adjuster for adjusting the signs of the temporally alternating predistorted I components and predistorted Q components of the predistorted output signal so that two temporally successive predistorted components have a first sign and two additional successive predistorted components, which follow said first-mentioned components in time, have a second sign, which is inverse to said first sign, so as to produce an output signal at an output of the I/Q modulator.