摘 要
無線傳感器網(wǎng)絡(luò)是由大量分布在監(jiān)測區(qū)域內(nèi)的能量有限的，并具有感知、計(jì)算和通信能力的微型傳感器節(jié)點(diǎn)，通過自組織的方式所組成的網(wǎng)絡(luò)。在具體應(yīng)用之前，必須根據(jù)特定的應(yīng)用環(huán)境準(zhǔn)則，確定傳感器節(jié)點(diǎn)的部署方案。覆蓋作為無線傳感器網(wǎng)絡(luò)中的一個(gè)基本問題，就是保證在一定服務(wù)質(zhì)量的前提下，如何實(shí)現(xiàn)網(wǎng)絡(luò)覆蓋范圍的最大化，以提供可靠的監(jiān)測服務(wù)。
本文主要在覆蓋問題基礎(chǔ)上，考慮節(jié)點(diǎn)的能量有效性，討論研究能量有效的無線傳感器網(wǎng)絡(luò)覆蓋優(yōu)化。本文的主要研究工作如下：
1. 能耗均衡的覆蓋策略
針對(duì)隨機(jī)高密度節(jié)點(diǎn)布設(shè)所導(dǎo)致的節(jié)點(diǎn)覆蓋區(qū)域重疊、網(wǎng)絡(luò)能耗過大和通信沖突等問題，在選取最優(yōu)覆蓋節(jié)點(diǎn)集合的基礎(chǔ)上，同時(shí)考慮網(wǎng)絡(luò)區(qū)域能耗的均衡問題，研究了一種基于遺傳算法的能耗均衡覆蓋策略。構(gòu)建概率感知模型網(wǎng)絡(luò)，定義一個(gè)能耗均衡系數(shù)用以表示網(wǎng)絡(luò)能耗均衡程度，以覆蓋率、工作節(jié)點(diǎn)數(shù)和網(wǎng)絡(luò)能耗均衡系數(shù)為優(yōu)化目標(biāo)，然后利用遺傳算法進(jìn)行求解，得到最優(yōu)網(wǎng)絡(luò)覆蓋。仿真結(jié)果表明，該覆蓋控制策略能夠在達(dá)到較高覆蓋率的同時(shí)，有效降低能耗并保證網(wǎng)絡(luò)能量均衡，從而保持網(wǎng)絡(luò)穩(wěn)定運(yùn)行和延長網(wǎng)絡(luò)生存時(shí)間。
2. 節(jié)能的移動(dòng)節(jié)點(diǎn)覆蓋優(yōu)化
針對(duì)基本粒子群算法在求解移動(dòng)節(jié)點(diǎn)覆蓋優(yōu)化問題時(shí)容易陷入早熟收斂的不足，研究了基于擾動(dòng)因子的粒子群覆蓋優(yōu)化，該方法將擾動(dòng)因子融入到粒子群算法的速度更新公式中，通過擾動(dòng)粒子速度指導(dǎo)粒子進(jìn)化；另外，將量子理論和粒子群算法相結(jié)合，研究了基于量子粒子群算法覆蓋優(yōu)化，該方法利用量子空間中粒子滿足集聚態(tài)性質(zhì)完全不同的特點(diǎn)，在整個(gè)可行空間內(nèi)進(jìn)行搜索，避免了粒子群算法容易陷入局部最優(yōu)的問題。結(jié)果表明，兩種改進(jìn)算法均能改善網(wǎng)絡(luò)覆蓋性能，并且量子粒子群方法可以減少平均移動(dòng)距離，達(dá)到節(jié)能覆蓋的目的。

關(guān)鍵詞 無線傳感器網(wǎng)絡(luò)；覆蓋優(yōu)化；能量有效；遺傳算法；粒子群算法


Abstract
Wireless sensor network is composed of a large number of energy limited micro-sensor nodes distributed in the monitoring regions, which have the sensing, computing and communicating capabilities through self-organized manner. Before the specific applications, the methods of deploying the sensor nodes should be determined according to the criteria of application-specific environments. As one of the fundamental problems in the wireless sensor network, the researches of coverage focus on the case that how to maximize the coverage regions and achieve the reliable area observation with quality of service.
Based on the problem of coverage, with the consideration of energy efficiency, this paper discusses and researches energy efficient coverage optimization of wireless sensor network. The main research works are as follows:
1. Energy-balanced coverage strategy
To solve the problems of coverage overlap、excessive energy consumption and communication conflicts caused by deploying nodes with high density, based on the selection of the optimal coverage set of nodes, an energy-balanced coverage strategy is researched. A network of probabilistic sensing model is built and an energy balance coefficient is set. Network coverage, working nodes and energy consumption coefficient are the optimization goals, then the genetic algorithm is used to get the optimal coverage solution. Simulation results show that the strategy can reduce and balance the energy consumption while ensuring the high network coverage, thus making the network work stably and prolonging the network lifetime efficiently.
2. Energy-efficient coverage optimization of dynamic nodes
When used to solve the coverage optimization problem of dynamic nodes, PSO easily falls into the local optimum. So the coverage optimization based on disturbance-factor PSO is researched. The strategy adds a disturbance factor to the updating formula of PSO, thus guiding the evolution; Then, with the combination of quantum theory and PSO, the coverage optimization based on QPSO is researched. The aggregation characteristic of every particle in the quantum space is unique, so the algorithm can search throughout the entire feasible region. Thus the QPSO, of which global search ability is much better than PSO, can avoid the disadvantages of being easily trapped into a local extreme. Simulation results show that the proposed algorithms are better than PSO in coverage optimization and the algorithm based on QPSO can eliminate the mean moving distance of the nodes, thus meeting the aim of energy-efficient coverage.

Key words wireless sensor networks; coverage optimization; energy efficient; genetic algorithm; particle swarm optimization algorithm
目 錄
摘 要 I
Abstract III
第1章 緒論 1
1.1 研究背景 1
1.1.1 無線傳感器網(wǎng)絡(luò)簡介 1
1.1.2 無線傳感器網(wǎng)絡(luò)的特點(diǎn) 3
1.1.3 無線傳感器網(wǎng)絡(luò)的關(guān)鍵技術(shù) 4
1.1.4 無線傳感器網(wǎng)絡(luò)的研究現(xiàn)狀與應(yīng)用 5
1.2 課題研究目的和意義 5
1.3 本文的主要工作 6
1.4 本文的組織結(jié)構(gòu) 7
第2章 無線傳感器網(wǎng)絡(luò)覆蓋問題 9
2.1 引言 9
2.2 無線傳感器網(wǎng)絡(luò)覆蓋分類 9
2.3 典型的覆蓋算法分析 12
2.3.1 基于靜態(tài)節(jié)點(diǎn)調(diào)度的覆蓋算法 12
2.3.2 基于移動(dòng)節(jié)點(diǎn)的覆蓋算法 14
2.4 覆蓋性能指標(biāo) 16
2.5 覆蓋算法評(píng)價(jià)標(biāo)準(zhǔn) 18
2.6 本章小結(jié) 19
第3章 基于遺傳算法的能耗均衡覆蓋策略 21
3.1 問題概述 21
3.1.1 傳感器節(jié)點(diǎn)覆蓋模型 22
3.1.2 網(wǎng)絡(luò)覆蓋模型 24
3.2 遺傳算法原理 24
3.2..