Power Allocation Under Transmitter Channel Uncertainty and QoS Constraints: Volumetric Water-Filling Solution
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| Title | Power Allocation Under Transmitter Channel Uncertainty and QoS Constraints: Volumetric Water-Filling Solution |
| Authors | |
| Abstract | We study optimal power allocation for a set of parallel channels when the transmitter has limited knowledge of the Channel State Information (CSI). This case is typical for mobile OFDMA systems like LTE and LTE-A where the transmitter relies on CSI feedback from a receiver that is subject to measurement errors, sparse sampling, quantization errors (especially noticeable in MIMO systems), processing and transmission delays. Based upon per-channel targeted Packet Error Rates (PER) we construct a power allocation scheme that maximizes the sum capacity. The optimal algorithm can be cast into a modified 3-D (Volumetric) version of the Water-Filling algorithm. Additionally, the solution obtained here improves performance of real-time delay sensitive traffic such as voice and real-time video by favoring the traffic with lower target PER. Simulationsshow that the gain in sum capacity over traditional Water-Filling solution can reach as high 90% in some cases. |
| Publisher | ACADEMY PUBLISHER |
| Date | 2012-09-01 |
| Source | Journal of Communications Vol 7, No 9 (2012): Special Issue: Interference Management in 4G Wireless Networks |
| Rights | Copyright © ACADEMY PUBLISHER - All Rights Reserved.To request permission, please check out URL: http://www.academypublisher.com/copyrightpermission.html. |