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.
@article{arxiv.1306.3440,
title = {Comparison of OFDM and SC-DFE Capacities Without Channel Knowledge at the Transmitter},
author = {Amanda de Paula and Cristiano Panazio},
journal= {arXiv preprint arXiv:1306.3440},
year = {2013}
}