Patent ID: 8665995

Claim:
A method, comprising: arranging, in a transmission circuitry, a first transmission signal to be transmitted on a first frequency channel and a second transmission signal to be transmitted on a second frequency channel, into a plurality of processing branches, wherein each processing branch includes signal components of both the first transmission signal and the second transmission signal, and wherein the first frequency channel and the second frequency channel are arranged symmetrically around a center frequency; frequency-converting each signal component first with an oscillator signal having a first frequency which corresponds to a frequency offset from the center frequency and again with another oscillator signal having a second frequency which corresponds to the center frequency; manipulating phases of the signal components in different processing branches so that the signal components of both the first transmission signal and the second transmission signal appearing on a mirror frequency channel as a result of the frequency-conversion with the oscillator signal having the second frequency have opposite phases in different processing branches; and combining the signal components in the different processing branches, thereby obtaining an up-converted transmission signal having the frequency-converted first transmission signal on the first frequency channel and the frequency-converted second transmission signal on the second frequency channel.