Signal processing arrangement and signal processing method

Signal processing arrangement and signal processing method 5 A signal processing arrangement for processing an input signal (x) has an adaptive predistorter (110, 160), an amplifier (130) and a down-converter (150). The amplifier (130) is configured to amplify a processed signal (y') to obtain an amplified signal (y"). The down-converter (150) is configured to multiply a version of the processed signal (y') with a version of the amplified signal (y"), one of the 10 signal versions being phase shifted, to obtain a first down-converted signal (z1, z1'), and to multiply the processed signal (y') with the amplified signal (y") to obtain a second down-converted signal (z2, z2'). The predistorter (110, 160) is configured to predistort the input signal (x) according to a predistortion characteristic to obtain the processed signal (y'), the predistorter (110, 160) being 15 further configured to adapt the predistortion characteristic based on the first down converted signal (z1, zi') and the second down-converted signal (z2, z2'). Fig. 1