We study energy-efficient power allocation among relays for lifetime maximization
in a dual-hop relay network operated by amplify-and-forward relays with battery
limitations. Power allocation algorithms are proposed for three different scenarios.
First, we study the relay cooperation case where all the relays jointly support
transmissions for a targeted data rate. By exploring the correlation of time-varying
relay channels, we develop a prediction-based relay cooperation method for optimal
power allocation strategy to improve the relay network lifetime over existing methods
that do not predict the future channel state, or assume the current channel state
remains static in the future.
Next, we consider energy-efficient relay selection for the single source-destination
case. Assuming finite transmission power levels, we propose a stochastic shortest path
approach which gives the optimal relay selection decision to maximize the network
lifetime. Due to the high computational complexity, a suboptimal prediction-based
relay selection algorithm, directly coming from previous problem, is created.
Finally, we extend our study to multiple source-destination case, where relay selection
needs to be determined for each source-destination pair simultaneously. The
network lifetime in the presence of multiple source-destination pairs is defined as the
longest time when all source-destination pairs can maintain the target transmission
rate. We design relay-to-destination mapping algorithms to prolong the network lifeii
time. They all aim at maximizing the perceived network lifetime at the current time
slot. The optimal max-min approach and suboptimal user-priority based approach
are proposed with different levels of computational complexity. / UOIT
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:OOSHDU.10155/188 |
| Date | 01 August 2011 |
| Creators | Zuo, Fangzhi |
| Contributors | Dong, Min |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Thesis |
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