Patent ID: 7072422

Claim:
A device for spectrally shaping a discrete-value transmission signal in a radio transmitter, comprising: a first input for receiving an in-phase component of the transmission signal; a second input for receiving a quadrature component of the transmission signal; a first shift register having N first memory locations, said first shift register connected to said first input; a second shift register having N second memory locations, said second shift register connected to said second input; a multiplexer unit having a plurality of multiplexers; a discrete-value filter circuit having a plurality of multipliers and at least one adder for spectrally shaping both the in-phase component and the quadrature component of the transmission signal, said multipliers being used, in a multiplex method, both for the in-phase component and for the quadrature component of the transmission signal; a first output for providing a filtered in-phase component of the transmission signal; a second output for providing a filtered quadrature component of the transmission signal; a demultiplexer unit; and a signal path; each of said memory locations of said first shift register having M signal taps, and each of said memory locations of said second shift register having M signal taps, M being greater than one; said multiplexer unit configured in the signal path downstream from said first shift register and said second shift register; said multiplexer unit configured in the signal path upstream of said filter circuit; and said demultiplexer unit configured in the signal path downstream of said filter circuit and upstream of said first output and said second output.