Imperfect Adaptation in Next Generation OFDMA Cellular Systems
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چکیده
Abstract— Most cellular standards for the forthcoming beyond 3G (B3G) and 4G technologies state Orthogonal FrequencyDivision Multiple Access (OFDMA) as the preferred multiplexing technique. OFDMA combines an efficient multiple access with Adaptive Quadrature Amplitude Modulation (AQAM) to maximize system performance while keeping the errors below a certain target. In order to achieve this objective, Channel Quality Indicators (CQI) are fed back from the receivers. However, potential errors and/or delay in the reception of such CQI as well as an imperfect channel estimation may lead to a system performance degradation. This paper analyzes the impact of an imperfect adaptation on a Long Term Evolution (LTE) cellular network.
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تاریخ انتشار 2010