A Novel Algorithm for Blind Detection of the Number of Transmit Antenna

In this paper, a novel algorithm is proposed to blindly detect the number of transmit antennas by exploiting the time-diversity of the fading channel. It employs a second-order moment and a fourth-order statistic of the received signal when the transmission occurs over a time-varying multiple-input single-output channel. When compared with information theoretic algorithms, it does not require the number of received antennas be larger than the number of transmit antennas, and when compared with existing feature-based algorithms, it does not require a priori information about the transmitted signal, such as preambles or pilots. Simulation results show that the proposed algorithm exhibits a good performance over a wide range of signal-to-noise-ratios (SNRs), and the probability of correct detection approaches one at low SNR values for various numbers of transmit antennas. Furthermore, it is robust to the modulation format and carrier frequency offset, and exhibits a good performance in the presence of the noise power mismatch and spatially correlated fading.