Improving OFDMA Performance Using
نویسنده
چکیده
Abstract — This paper analyzes the performance of an orthogonal frequencydivision multiple access (OFDMA) scheme in which the carriers assigned to a user are uniformly spaced across the channel bandwidth and code-division multiplexing is used between them. Zero forcing and minimum mean-square error equalization and maximum-likelihood detection are used to compensate for multipath fading. It is found that code-division multiplexing recovers most of the frequency diversity loss inherent to OFDMA. The analyzed scheme makes it possible to benefit from the advantages of OFDMA and approach the performance of MC-CDMA.
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تاریخ انتشار 2005