METHOD OF REDUCING THE VARIANCE OF A SIGNAL-TO-NOISE RATION ESTIMATE FOR A SIGNAL WITH DIFFERENTIAL PHASE AND COHERENT AMPLITUDE MODULATION

摘要

The present invention reduces the variance of the differential phase and coherent in amplitude modulation of the signal-to-noise ratio estimate signal relates to a method for. The present invention is to calculate the samples of the noise power affecting the system, the error (1) and (4) by moving the corresponding point of the first ring (6) of the constellations, as the ring is transmitted and that the amplitude and phase increment errors obtained in the receiver without any corrections in combination is characterized in calculating the square of the absolute value of the error vector. The in such a way, the present invention minimizes the variance of the sample obtained by the other even and odd bit values for each carrier, and equalization will be used by the system. In addition, the present invention reduces the variance of the signal-to-noise ratio estimate in a multi-user digital communication systems. The aforementioned estimation can be fit to the same channel to be necessary for selection of the number of bits per carrier, as well as support information necessary when the diversity receiver used.