Spectral Efficiency of OFDMA Cognitive Radios under Imperfect Cross-Link Knowledge

H. Saki; M. Shikh-Bahaei

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arXiv · 1710.08277

Spectral Efficiency of OFDMA Cognitive Radios under Imperfect Cross-Link Knowledge

H. Saki·M. Shikh-Bahaei

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Abstract

We analyze the spectral efficiency performance and limits of orthogonal frequency-division multiple access (OFDMA) cognitive radios (CRs) with an imperfect availability of cross-link knowledge. In particular, in contrast to the conventional `average' and `worst' cases of channel estimation error in the literature, we propose a stochastic approach to mitigate the total imposed interference on primary users. Channel-adaptive resource allocation algorithms are incorporated to optimize the cognitive system functionality under transmit and interference power constraints. An expression for the cumulative density function (cdf) of the received signal-to-interference-plus-noise ratio (SINR) is developed to evaluate the average spectral efficiency. Analytical derivations and results are confirmed through computer simulations.

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H. Saki, M. Shikh-Bahaei. 2017-10-19. Spectral Efficiency of OFDMA Cognitive Radios under Imperfect Cross-Link Knowledge. https://arxiv.org/abs/1710.08277

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