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Simultaneous Estimation Of Multi-Relay Mimo Channels, Hani Mehrpouyan, Steven D. Blostein, Björn Ottersten
Simultaneous Estimation Of Multi-Relay Mimo Channels, Hani Mehrpouyan, Steven D. Blostein, Björn Ottersten
Hani Mehrpouyan
This paper addresses training-based channel estimation in distributed amplify-and-forward (AF) multi-input multi-output (MIMO) multi-relay networks. To reduce channel estimation overhead and delay, a training algorithm that allows for simultaneous estimation of the entire MIMO cooperative network’s channel parameters at the destination node is proposed. The exact Cramér-Rao lower bound (CRLB) for the problem is presented in closed-form. Channel estimators that are capable of estimating the overall source-relay-destination channel parameters at the destination are also derived. Numerical results show that while reducing delay, the proposed channel estimators are close to the derived CRLB over a wide range of signal-to-noise ratio values …
Phase Noise And Carrier Frequency Offset In Ofdm Systems: Joint Estimation And Hybrid Cramér-Rao Lower Bound, Omar Hazim Salim, Ali A. Nasir, Hani Mehrpouyan, Wei Xiang
Phase Noise And Carrier Frequency Offset In Ofdm Systems: Joint Estimation And Hybrid Cramér-Rao Lower Bound, Omar Hazim Salim, Ali A. Nasir, Hani Mehrpouyan, Wei Xiang
Hani Mehrpouyan
In this paper, a new iterative pilot-aided algorithm based on expectation conditional maximization (ECM) for joint estimation of Wiener phase noise (PHN) and carrier frequency offset (CFO) in orthogonal frequency division multiplexing (OFDM) systems is proposed. Next, a new expression for the hybrid Cramér-Rao lower bound (HCRB) for joint estimation of PHN and CFO in OFDM systems is derived. Numerical results show that the proposed estimator outperforms existing algorithms in terms of mean square error while performing close to the derived HCRB at moderate PHN variances. Moreover, the proposed estimator is found to be computationally more efficient than existing algorithms …