Comparison of OFDM and SC-DFE Capacities Without Channel Knowledge at the Transmitter

Amanda de Paula; Cristiano Panazio

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arXiv · 1306.3440

Comparison of OFDM and SC-DFE Capacities Without Channel Knowledge at the Transmitter

Amanda de Paula·Cristiano Panazio

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Abstract

This letter provides a capacity analysis between OFDM and the ideal SC-DFE when no channel knowledge is available at the transmitter. Through some algebraic manipulation of the OFDM and SC-DFE capacities and using the concavity property of the manipulated capacity function and Jensen's inequality, we are able to prove that the SC-DFE capacity is always superior to that of an OFDM scheme for 4- and 16-QAM for any given channel. For higher-order modulations, however, the results indicate that OFDM may only surpass the ideal SC-DFE capacity by a small amount in some specific scenarios.

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Amanda de Paula, Cristiano Panazio. 2013-06-14. Comparison of OFDM and SC-DFE Capacities Without Channel Knowledge at the Transmitter. https://arxiv.org/abs/1306.3440

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