由於階層式的感測網路，能排除多餘的感測資訊和遞減多餘的溝通負擔，對於增加網路的延展性和延長網路的壽命，有著非常重要的影響。在本篇論文，我們專注在兩階層式異質性感測網路的轉送節點上，當轉送節點在沒有排班的情況下傳送感測資訊，碰撞機會必然增加，使太多的電量花費在重傳資訊和傾聽頻道上。為了避免多餘的電量消耗，我們根據接收訊號強度建構出一個網格網路，並為網格上的每個轉送節點命名IP，接著，所有樹葉節點根據接收訊號強度加入某個叢集並命名IP，每個感測節點透過這個專屬IP進行TDMA的排班任務，感測節點在特定的時槽來到時，才醒來傳送或接收資訊，剩餘的時間則進入睡眠狀態，節省電量的消耗。此外，我們提出了三個路由協定(DTS、REARBS、VIPOS)，平衡骨幹與非骨幹轉送節點的電量消耗，延長網路的壽命。由模擬結果得知，VIPOS是三個方法中，壽命最長者。

Due to hierarchical sensor networks is capable to elimination extra sensing information and reduce extra communication load, it is remarkably important to increase scalability of network and prolong lifetime of network. In the paper, we focus on relay nodes of two-layered heterogeneous sensor networks. When relay nodes transmit data without scheduling, the collision probability must increase. It will cost too much for energy to re-transmission data and listening channel. To avoid extra energy consumption, we build a grid network according to RSS, and naming IP for every relay node on the grid network. Then, all leaf nodes join a certain cluster and naming IP according to RSS. Through the exclusive IP it schedule mission for TDMA. Only when relay node comes in specific slot, it wakes up to transmit or receive data, the remaining time to sleep and save power consumption. Besides, in order to balance energy consumption of backbone or non-backbone relay nodes and prolong lifetime of network, we proposal three routing protocol (DTS、REARBS、VIPOS). According to simulation results, VIPOS is the longest lifetime above them.

Chapter1 Introduction…………………………………………….………….-1-
1.1 Overview…………………………………………………………….......-1-
1.2 Motivation……………………………………………………………….-5-
1.3 Thesis Framework……………………….………………………………-6-
Chapter2 Related Work………...……………………………………….……-7-
2.1 Placement of Relay Nodes with Energy Constraints………..……………..-8-
2.1.1 The Placement of First Phase Relay Nodes (FPRNs)…………..........-8-
2.1.2 The Placement of Second Phase Relay Nodes (SPRNs)…………..-10-
2.2 Localized Heuristic Algorithms…………………………………………-11-
2.2.1 Nearest-To-BS-First Algorithm……………………...……………-11-
2.2.2 Max-Residue-Capacity-First Algorithm……………………...…...-13-
2.2.3 Best-Effort-Relaying Algorithm………………………...………...-14-
Chapter3 Proposal Scheme………………………………….……………...-17-
3.1 Network Model…………………...…………………………………….-17-
3.2 Energy Model……………………………………………………...…...-18-
3.3 Naming Virtual IP………………………………………….…...………-19-
3.3.1 Virtual IP Format……………………………...………………….-19-
3.3.2 Naming Relay Node ………………………..……………………-20-
3.3.3 Naming Leaf Node……………………………………………….-25-
3.3.4 Relationship between father node and child node…………….........-25-
3.4 TDMA Scheduling………………………………………………….......-27-
3.4.1 Frame Structure………………………………….……………….-27-
3.4.2 Leaf Node Scheduling…………………………....………………-28-
3.4.3 Non-Backbone Relay Node Scheduling…………………………..-28-
3.4.4 Backbone Relay Node Scheduling………………………………..-30-
3.5 Dynamic Threshold Scheme (DTS)…………………………………….-32-
3.6 Residue Energy and Residue Buffer Scheme (REARBS)……………….-37-
3.7 Virtual IP Orientation Scheme (VIPOS)……………………………........-42-
Chapter4 Simulation………………………………………………………..-47-
4.1 Simulation Parameters………………………………………………….-48-
4.2 Results and Analysis……………………………………………………-49-
Chapter5 Conclusion……………………………………………………….-52-
References................................................................................................................-53-

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