A method for robust classification of QPSK signals (Q1876951)

In digital communications the transmitting procedure called quadriphase-shift keying plays an important role. In such a case, the information is contained in the phases taken by a sinusoidal signal at certain prescribed times. When the (inherent) disturbing signal is an additive Gaussian noise, there is a detector (classifier) which is optimal. When the noise is not Gaussian the optimality is lost. Here, a classifier is introduced whch preserves the optimality by the use of these signal samples. The proposed method is tested by some computer simulations.