method for demodulation of higher-level mqam signals without knowledge of the transmitted symbols

摘要

The method involves calculating a clock phase error. The estimated error is used for compensating the corresponding time-shift of the base band signals using interpolation. The carrier frequency shift and the carrier phase shift are calculated using the maximum likelihood theory with use of the Fourier transformation or applying convolution in the time domain. The frequency and phase shifts are used to compensate the data sequence. Preferably, the ratio of the calculated mean value of the symbol values to the statistical symbol mean value of the MQAM modulation is calculated. The calculated ratio corresponds to the dynamic error and is used for the dynamic compensation of the sampled data sequence.