Hierarchical space–time block codes signals classification using higher order cumulants

An efficient method for blind classification of space–time block codes (STBCs) based on fourth-order cumulants is proposed for a single receiver antenna. This paper presents a model of received STBCs signals in multiple input single output (MISO) communication systems and applies the characteristics of coding matrices to derive analytical expressions for the fourth-order cumulants to be used as the basis of an algorithm. The fourth-order cumulants at various delay vectors present non-null values that depend on the transmitted STBCs. Tests of nullity are accomplished by hypothesis testing. The proposed algorithm avoids the need for a priori information of modulation scheme, channel coefficients, and noise power. Consequently, it is well suited for non-cooperative scenarios. Simulations show that this method performs well even at low signal-to-noise ratios (SNRs).