On the Optimal Allocation of Downlink Resources in OFDM-Based Wireless Networks
Orthogonal Frequency Division Multiplexing (OFDM) is used in both 802.11 and 802.16  wireless network standards and is being evaluated for Fourth Generation (4G) networks. Its tolerance to frequency selective fading has made it an attractive choice for these broadband wireless networks. In both downlink and uplink directions, resources can be allocated in three dimensions, frequency, time and power. In both cases the resource allocation is performed primarily by the BS. In this paper we focus on the allocation of downlink resources when such a network is used for Quality of Service (QoS) applications. We formulate and solve the corresponding optimization problem and use the solution to design simple, practical algorithms. In doing so we take into account practical details that have not been addressed in previous work.
KeywordsUtility Function Orthogonal Frequency Division Multiplex Power Allocation Optimal Allocation Optimal Power Allocation
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