Upper bound on the periodic autocorrelation of unified complex Hadamard transforms sequences

The periodic autocorrelation (PAC) properties of a family of orthogonal sequences, the unified complex Hadamard transforms (UCHTs), are analyzed in this paper. The family is divided into a few groups in accordance to different characteristics of the sequences. Different upper bounds on the out-of-phase PAC are found for each group. The performance of the UCHTs sequences is compared with the Walsh-Hadamard sequences. It is shown that some UCHTs sequences provide better upper bound on the out-of-phase PAC.