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Energy-Efficient Resource Allocation in Time Division Multiple-Access over Fading Channels

Xin Wang·Georgios B. Giannakis
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Abstract

We investigate energy-efficiency issues and resource allocation policies for time division multi-access (TDMA) over fading channels in the power-limited regime. Supposing that the channels are frequency-flat block-fading and transmitters have full or quantized channel state information (CSI), we first minimize power under a weighted sum-rate constraint and show that the optimal rate and time allocation policies can be obtained by water-filling over realizations of convex envelopes of the minima for cost-reward functions. We then address a related minimization under individual rate constraints and derive the optimal allocation policies via greedy water-filling. Using water-filling across frequencies and fading states, we also extend our results to frequency-selective channels. Our approaches not only provide fundamental power limits when each user can support an infinite number of capacity-achieving codebooks, but also yield guidelines for practical designs where users can only support a finite number of adaptive modulation and coding (AMC) modes with prescribed symbol error probabilities, and also for systems where only discrete-time allocations are allowed.

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Xin Wang, Georgios B. Giannakis. 2005-11-24. Energy-Efficient Resource Allocation in Time Division Multiple-Access over Fading Channels. https://arxiv.org/abs/cs/0511086

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