Blind Modulation Classification for Alamouti STBC System With Transmission Impairments

The novel classification algorithm developed in this letter exploits the structure of the Alamouti (AL) space-time block code (STBC) to blindly identify the modulation format of the received signal. By exploiting the statistical properties of a correlation function of two signals received by different antennas, the proposed algorithm classifies different modulation formats in the presence of the carrier phase and frequency offsets, without prior information about channel coefficients and block timing synchronization. Monte Carlo simulations are carried out to assess the classification performance of the proposed algorithm in the presence of the aforementioned impairments and clock timing synchronization error.