Joint carrier synchronization for PSK signals from multiple independent antennas and Cramer-Rao bounds

In this paper, we investigate the PSK parameter estimation problem in antenna arraying system. The Cramer-Rao lower bounds (CRLBs) for non-data-aided (NDA) BPSK/QPSK frequency and phase estimation using mutual information offered by multiple antenna elements are derived. The results show that the CRLBs become smaller as the antenna number grows, and indicate that utilizing information between antennas is beneficial to parameter estimation. In addition, a joint carrier phase estimator based on maximum-likelihood (ML) principle using the mutual information of antenna array elements is presented. Simulations show that the proposed estimator improves estimation accuracy, especially at low SNR levels.