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arXiv · 1003.4302

Optimal Unitary Linear Processing for Amplify-and-Forward Cooperative OFDM systems

Min Dong·Mahdi Hajiaghayi·Ben Liang
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Abstract

In this paper, we consider the amplified-and-forward relaying in an OFDM system with unitary linear processing at the relay. We proposed a general analytical framework to find the unitary linear processing matrix that maximizes the system achievable rate. We show that the optimal processing matrix is a permutation matrix, which implies that a subcarrier pairing strategy is optimal. We further derived the optimal subcarrier pairing schemes for scenarios with and without the direct source-destination path for diversity. Simulation results are presented to demonstrate the achievable gain of optimal subcarrier pairing compared with non-optimal linear processing and non-pairing.

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Min Dong, Mahdi Hajiaghayi, Ben Liang. 2012-04-26. Optimal Unitary Linear Processing for Amplify-and-Forward Cooperative OFDM systems. https://arxiv.org/abs/1003.4302

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