Tez No	İndirme	Tez Künye	Durumu
400760		Energy-efficient channel access and routing protocols for multi-hop wireless networks / Yazar:FİKRET SİVRİKAYA Danışman: PROF. BÜLENT YENER Yer Bilgisi: Rensselaer Polytechnic Institute / Yurtdışı Enstitü Konu:Bilgisayar Mühendisliği Bilimleri-Bilgisayar ve Kontrol = Computer Engineering and Computer Science and Control Dizin:	Onaylandı Doktora İngilizce 2007 170 s.
Recent research eorts on multi-hop wireless networks are motivated and driven by two important phenomena: an ever increasing demand for ubiquitous access to online information and services, and a strong desire and need to capture and analyze data from physical phenomena surrounding us in our daily lives. The rst of the two constitutes an inspiration for wireless mesh networks, as the latter does for wireless sensor networks. In this thesis, we address the energy-ecient media access control (MAC) and routing issues on multi-hop wireless networks. Our major contributions are threefold. First, we propose a set of contention-free MAC protocols that do not rely on global time synchronization and that are possessed of the desired characteristics of a multi-hop wireless network protocol; i.e. they are energy-saving, distributed, and self-stabilizing. Our protocols attest that distributed and asynchronous slot assignment with reasonable frame sizes and throughput is possible in multi-hop wireless networks. Second, we present the rst routing protocols that -to the best of our knowledgeimprove the QoS level of Spatial TDMA (STDMA) MAC protocols by eectively decreasing the end-to-end delay in wireless sensor and mesh networks. In large multi-hop wireless networks, where data is routed over several hops, the end-toend latency may be signicantly large, especially when a reservation-based channel access protocol is used. We show that by exploiting the relative timing of nodes' slots in the underlying STDMA protocol, signicant performance gain is possible compared to the shortest-hop based conventional routing approaches. Third, we propose a general framework for a new hybrid media access scheme based on the idea of spatially limiting the contention in multi-hop wireless networks. The channel assignment component of the hybrid access scheme employs a novel approach for carefully selecting the set of contending nodes such that the hidden terminals are completely eliminated. Hence, in the contention-based component of the hybrid access scheme, only the spatially close (neighbor) nodes contend for the channel as if in a single-hop network, which can be handled much more eciently by a carrier-sense multiple access (CSMA) scheme. In order to assess the performance of the proposed scheme under dierent network conditions, we provide and utilize a general framework for the formal analysis of CSMA and CSMA/CA (collision avoidance) schemes for multi-hop wireless networks, which can capture under-saturation trac loads unlike prior work.