System and method for representing a multi-tone signal

Abstract

The present invention is related to a system () for determining a representation of a multi-tone signal () comprising a plurality of phase coherent tones, at least two of said phase coherent tones being modulated by a modulating signal, said system comprising an input () for applying the multi-tone signal (), phase coherent mixing means () for demodulation in connection with data acquisition means () for digitization, said mixing means and data acquisition means arranged for being fed with the multi-tone signal and with a reference signal () comprising said phase coherent tones, each pair of phase coherent tones having a fixed phase difference, whereby the data acquisition means is arranged for being triggered by a trigger signal () for yielding a representation of said modulation signals with fixed delay, processing means () arranged for receiving digital signals output from the data acquisition means and for comparing phase information of a downconverted tone of the multi-tone signal after demodulation with phase information derived from the corresponding tone of the demodulated reference signal and further arranged for controlling the phase coherent mixing means for sequential downconversion, such that a representation of said multi-tone signal can be determined.