Co-prime sampling for higher-order statistics with application to LTE channel estimation

This paper studies higher-order statistics of non-Gaussian signal using temporal co-prime sampling. We extend co-prime sampling to pairwise co-prime sequences (PCS) to derive higher-order statistics (HOS), and analyze the computational complexity of PCS-based HOS algorithm for both parametric and nonparametric methods. Compared to the existing HOS algorithms, the proposed algorithm vastly reduces the computation complexity by several orders in terms of the length of segmentation window. We also apply PCS-based HOS algorithm to estimate the coefficients of simplified LTE spacial channel model only based on its outputs. Our simulations show that 3rd-order PCS-based HOS achieves 80% performance gain compared to the existing HOS with the same computational complexity, or it has 12% performance loss with 15% complexity compared to the counterpart processing the same length of signal.