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arXiv · 1202.3468

Partially-blind Estimation of Reciprocal Channels for AF Two-Way Relay Networks Employing M-PSK Modulation

Saeed Abdallah·Ioannis N. Psaromiligkos
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Abstract

We consider the problem of channel estimation for amplify-and-forward two-way relays assuming channel reciprocity and M-PSK modulation. In an earlier work, a partially-blind maximum-likelihood estimator was derived by treating the data as deterministic unknowns. We prove that this estimator approaches the true channel with high probability at high signal-to-noise ratio (SNR) but is not consistent. We then propose an alternative estimator which is consistent and has similarly favorable high SNR performance. We also derive the Cramer-Rao bound on the variance of unbiased estimators.

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Saeed Abdallah, Ioannis N. Psaromiligkos. 2012-02-15. Partially-blind Estimation of Reciprocal Channels for AF Two-Way Relay Networks Employing M-PSK Modulation. https://arxiv.org/abs/1202.3468

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