Patent ID: 7313204
Filing Date: 2007-12-25
Classification: H04L

Abstract:
1. A transmission and reception method in a digital telecommunications system, which comprises: at a transmitter end, rotating each data symbol in a predetermined initial sequence known to a receiver through a phase rotation factor specific for a type of modulation being used to thereby form rotated data symbols; at a receiver end, derotating the rotated data symbols through different phase rotation factors to generate a derotated sequence; and forming a correlation function between the derotated sequence and the initial sequence based on an assumed temporal position of the initial sequence contained in a signal received at the receiver end for each phase rotation factor, wherein a temporal position of the initial sequence is known up to a certain accuracy; forming a summation of products between the derotated sequence and the initial sequence for individual moments in time from the correlation function, and squaring a magnitude of the summation to form squares; and comparing the squares of the magnitudes and determining therefrom a modulation type used at the transmitter end.