From Cell Capacity to Subcarrier Allocation in Multi-User OFDM
نویسنده
چکیده
In this paper we show how a fundamental result from information theory can be used to calculate the aggregate channel capacity in the uplink of an access point or a base station. The fundamental limits for this cell capacity provide an upper bound for any practically implementable multiple-access scheme. The capacity loss due to various implementation constraints is evaluated and a method for adaptive subcarrier allocation in OFDMA is presented. This method is based on the famous iterative water-filling algorithm and results in a surprisingly simple algorithm for the subcarrier allocation in OFDMA.
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