Patent ID: 8115543

Claim:
An upstream unit ( 1 ) for a switched power amplifier ( 2 ) of a high-frequency transmission circuit ( 16 ), comprising a first signal input ( 3 ) for a high-frequency, phase-modulated first input signal ( 18 , 41 ); a second signal input ( 4 ) for a second input signal ( 19 ) having a low frequency in comparison with the first input signal ( 18 ); a controllable first delay unit ( 5 ) to which the first input signal ( 18 ) is supplied and to which a first control signal ( 20 ) is supplied via a first control input ( 6 ) and which is configured to output the first input signal ( 18 ) with a first delay that depends on the first control signal ( 20 ); a controllable second delay unit ( 7 ) to which the first input signal ( 18 ) is supplied and to which a second control signal ( 21 ) is supplied via a second control input ( 8 ) and which is configured to output the first input signal ( 18 ) with a second delay that depends on the second control signal and which is longer than the first delay; a pulse generator ( 9 ) which is connected on the input side to the first and to the second delay unit ( 5 , 7 ) and configured to generate and output a pulsed and pulse-length modulated output signal ( 22 ), wherein the duration of the rising edges of the output signal ( 22 ) from the pulse generator ( 9 ) depends on the output signal ( 23 ) from the first delay unit ( 5 ) and the duration of the falling edges of the output signal ( 22 ) from the pulse generator depend on the output signal ( 24 ) from the second delay unit ( 7 ); and a control unit ( 10 ) which is configured to generate and output the first control signal ( 20 ) according to the second input signal ( 19 ) and the output signal ( 22 ) from the pulse generator ( 9 ) and to generate and output the second control signal ( 21 ) according to the second input signal ( 3 ) and the output signal ( 22 ) from the pulse generator.