【摘要】：面對(duì)日益迫切的國(guó)民健康需求,研究低成本、可穿戴、可無(wú)縫融入日常生活、不受限于時(shí)間與地點(diǎn)的醫(yī)療監(jiān)測(cè)關(guān)鍵技術(shù)及應(yīng)用至關(guān)重要。無(wú)線體域網(wǎng)WBAN (Wireless Body Area Network)是由一系列低功耗、微型化、輕量級(jí)、可置于體表或植入體內(nèi)、可提供實(shí)時(shí)數(shù)據(jù)、具備無(wú)線通信能力的傳感節(jié)點(diǎn)組成的網(wǎng)絡(luò),為該類醫(yī)療監(jiān)測(cè)提供了創(chuàng)新性解決方案；而MAC層涉及WBAN的能耗、可擴(kuò)展性、高效通信,以及個(gè)人醫(yī)療數(shù)據(jù)的隱私性與安全性等諸多核心問(wèn)題,因此本文針對(duì)WBAN的MAC層關(guān)鍵技術(shù)開(kāi)展研究。本文按照MAC層“理論建�！鷧f(xié)議設(shè)計(jì)→安全協(xié)議”的研究思路,從緩存容量有限狀態(tài)下基于CSMA/CA機(jī)制的MAC層協(xié)議性能評(píng)估模型,低能耗、高時(shí)隙利用率、可滿足異構(gòu)醫(yī)療數(shù)據(jù)QoS需求的短中斷混合MAC協(xié)議設(shè)計(jì),以及基于Fuzzy Commitment的MAC層輕量級(jí)密鑰協(xié)商協(xié)議設(shè)計(jì)三方面,對(duì)面向醫(yī)療監(jiān)測(cè)的無(wú)線體域網(wǎng)MAC層關(guān)鍵技術(shù)進(jìn)行了深入研究,并構(gòu)建了以WBAN和云計(jì)算技術(shù)為支撐的實(shí)時(shí)醫(yī)療監(jiān)測(cè)系統(tǒng),在實(shí)際應(yīng)用場(chǎng)景內(nèi)對(duì)所研究技術(shù)進(jìn)行了分析驗(yàn)證。本文的主要研究成果和創(chuàng)新點(diǎn)包括以下幾方面：(1)提出了一種適用于非飽和條件,可對(duì)基于IEEE 802.15.6 CSMA/CA的WBAN MAC協(xié)議進(jìn)行性能評(píng)估的分析模型。模型采用三維離散馬爾科夫鏈來(lái)模擬非飽和狀態(tài)下無(wú)線體域網(wǎng)節(jié)點(diǎn)的回退機(jī)制,通過(guò)求解馬爾科夫鏈得到不同優(yōu)先級(jí)節(jié)點(diǎn)競(jìng)爭(zhēng)到信道資源的概率；采用嵌入式馬爾科夫鏈分析緩存中的數(shù)據(jù)包隊(duì)列,得到穩(wěn)態(tài)時(shí)緩存中的數(shù)據(jù)包隊(duì)列分布；基于概率母函數(shù)和利特爾法則,分別計(jì)算出數(shù)據(jù)包的平均服務(wù)時(shí)間和平均排隊(duì)時(shí)延,進(jìn)而得到數(shù)據(jù)包的平均時(shí)延和網(wǎng)絡(luò)吞吐量；通過(guò)計(jì)算每個(gè)節(jié)點(diǎn)的能量消耗,得到整個(gè)網(wǎng)絡(luò)的能效。通過(guò)Matlab仿真驗(yàn)證了理論模型的正確性,結(jié)果表明該模型可以對(duì)非飽和條件下的無(wú)線體域網(wǎng)MAC協(xié)議性能進(jìn)行有效評(píng)估。(2)以無(wú)線體域網(wǎng)醫(yī)療監(jiān)測(cè)為應(yīng)用目標(biāo),設(shè)計(jì)了一種混合型媒體接入?yún)f(xié)議(I-MAC)。通過(guò)對(duì)超幀結(jié)構(gòu)與時(shí)隙分配的設(shè)計(jì)改進(jìn),I-MAC可提高能量利用效率與時(shí)隙利用效率,并同時(shí)能保證數(shù)據(jù)的實(shí)時(shí)性與可靠性要求。I-MAC采用較長(zhǎng)超幀結(jié)構(gòu)以消除多余信標(biāo)收發(fā)所需能耗,從而提高能量利用效率；并將大多數(shù)時(shí)隙分配為GTS時(shí)隙,以滿足傳輸周期性醫(yī)療監(jiān)測(cè)應(yīng)用所產(chǎn)生大量數(shù)據(jù)的帶寬需求；針對(duì)隨機(jī)緊急監(jiān)測(cè)數(shù)據(jù),特殊設(shè)計(jì)了中斷時(shí)隙進(jìn)行傳輸并保證這些數(shù)據(jù)的實(shí)時(shí)性與可靠性要求。仿真結(jié)果表明,不同參數(shù)配置的I-MAC協(xié)議的能量效率、時(shí)隙利用率均高于802.15.4,且同時(shí)能夠滿足數(shù)據(jù)的時(shí)延要求；當(dāng)每個(gè)中斷周期內(nèi)的隨機(jī)性醫(yī)療監(jiān)測(cè)數(shù)據(jù)量小于1時(shí),I-MAC協(xié)議可顯著提升無(wú)線體域網(wǎng)的性能,對(duì)于具有低非周期性隨機(jī)數(shù)據(jù)的無(wú)線體域網(wǎng),協(xié)議也具有良好的性能。(3)對(duì)體域網(wǎng)中基于噪聲生理信號(hào)的密鑰協(xié)商機(jī)制進(jìn)行了系統(tǒng)性深入研究,其中詳細(xì)分析了兩種主流密鑰協(xié)商技術(shù)Fuzzy Commitment和Fuzzy Vault的優(yōu)勢(shì)和劣勢(shì),并根據(jù)各自的特點(diǎn)進(jìn)行了細(xì)化分類。對(duì)體域網(wǎng)節(jié)點(diǎn)與協(xié)調(diào)器間的單跳與多跳傳輸方式的能耗進(jìn)行了細(xì)致的對(duì)比分析,指出對(duì)于體表傳感節(jié)點(diǎn),單跳傳輸更加節(jié)能,為構(gòu)建低能耗的體域網(wǎng)密鑰管理模型打下了基礎(chǔ)。提出了一種基于Fuzzy Commitment和ECG信號(hào)的輕量級(jí)MAC層密鑰協(xié)商協(xié)議。在該協(xié)議的初始化階段,通過(guò)共享密鑰產(chǎn)生承諾的方式避免了體域網(wǎng)間的互干擾,并能夠抵御基于超寬帶雷達(dá)遙測(cè)的新型攻擊方式；在密鑰協(xié)商階段,利用時(shí)間窗機(jī)制實(shí)現(xiàn)了噪聲生理信號(hào)的弱同步,避免了精確時(shí)間同步所帶來(lái)的巨大能耗；采用了“以計(jì)算能耗代替?zhèn)鬏斈芎摹钡乃悸?利用簡(jiǎn)單的比特級(jí)運(yùn)算避免了由于生理信號(hào)噪聲造成的密鑰協(xié)商失敗所帶來(lái)的協(xié)議重啟,極大地節(jié)約了能量。分析表明,該協(xié)議既保障了WBAN密鑰協(xié)商的低能耗需求,又提升了協(xié)議的抗攻擊性能。(4)在上述研究?jī)?nèi)容的基礎(chǔ)上,通過(guò)詳細(xì)的軟硬件設(shè)計(jì)及關(guān)鍵技術(shù)的研究,構(gòu)建了以無(wú)線體域網(wǎng)為支撐的實(shí)時(shí)醫(yī)療監(jiān)測(cè)系統(tǒng)。系統(tǒng)以多樣化的醫(yī)療傳感器為節(jié)點(diǎn),以設(shè)計(jì)完成的智能云健康檢測(cè)儀為智能協(xié)調(diào)器,實(shí)現(xiàn)了輕量級(jí)WBAN的快速部署,完成了人體多類醫(yī)學(xué)生理指標(biāo)的精準(zhǔn)感知與監(jiān)測(cè)；數(shù)據(jù)經(jīng)智能處理后,通過(guò)自適應(yīng)的異構(gòu)網(wǎng)絡(luò),上傳至云計(jì)算中心的醫(yī)療監(jiān)測(cè)云平臺(tái),實(shí)現(xiàn)了云端的醫(yī)療數(shù)據(jù)智能解析、處理、存儲(chǔ)和展示,并通過(guò)移動(dòng)APP形成醫(yī)療監(jiān)測(cè)的閉環(huán),完成了健康數(shù)據(jù)的實(shí)時(shí)檢測(cè)、移動(dòng)查詢、遠(yuǎn)程監(jiān)護(hù)與診斷等功能,并通過(guò)心電數(shù)據(jù)的完整測(cè)試,證明依托無(wú)線體域網(wǎng)可以有效進(jìn)行遠(yuǎn)程實(shí)時(shí)醫(yī)療監(jiān)測(cè),具有良好的應(yīng)用價(jià)值。
[Abstract]:In the face of the increasingly urgent national health needs, it is essential to study low-cost, wearable, seamless integration into daily life, key technologies and applications of medical monitoring that are not limited to time and place. The network composed of sensor nodes with real-time data and wireless communication capabilities provides innovative solutions for this kind of medical monitoring; and the MAC layer involves many core issues such as WBAN energy consumption, scalability, efficient communication, privacy and security of personal medical data, so this paper focuses on the key technologies of the MAC layer of WBAN. According to the research idea of MAC Layer "Theoretical Modeling-Protocol Design-Security Protocol", this paper discusses the performance evaluation model of MAC Layer protocol based on CSMA/CA mechanism under limited buffer capacity, the design of short interrupt hybrid MAC protocol with low energy consumption and high slot utilization, which can meet the QoS requirements of heterogeneous medical data, and the design of Fuzzy Commitm-based MAC protocol. In this paper, the key technologies of MAC layer in wireless body area network for medical monitoring are deeply studied, and a real-time medical monitoring system based on WBAN and cloud computing technology is constructed. The research results are analyzed and verified in practical application scenarios. The innovations are as follows: (1) An analytical model for evaluating the performance of WBAN MAC protocol based on IEEE 802.15.6 CSMA/CA under unsaturated conditions is proposed. The model uses three-dimensional discrete Markov chains to simulate the backoff mechanism of nodes in wireless body area networks under unsaturated conditions. The model is obtained by solving Markov chains. The probabilities of different priority nodes competing for channel resources are analyzed by using embedded Markov chain to obtain the packet queue distribution in steady-state cache. Based on probability generating function and Littler's law, the average service time and queue delay of packets are calculated respectively, and then the packets are obtained. Mean time delay and network throughput; energy efficiency of the whole network is obtained by calculating the energy consumption of each node. The correctness of the theoretical model is validated by MATLAB simulation. The results show that the model can effectively evaluate the performance of MAC protocol in wireless body area network under unsaturated conditions. (2) The application of wireless body area network medical monitoring Aim, a hybrid media access protocol (I-MAC) is designed. By improving the design of superframe structure and slot allocation, I-MAC can improve the efficiency of energy utilization and slot utilization, and ensure the real-time and reliability requirements of data. I-MAC uses a longer superframe structure to eliminate the energy consumption required for redundant beacon transceiver and receiver, thereby improving the efficiency. Most of the time slots are allocated to GTS slots to meet the bandwidth requirement of transmitting large amounts of data generated by periodic medical monitoring applications. The interrupt slots are designed to transmit the random emergency monitoring data and ensure the real-time and reliability of the data. The simulation results show that different parameters are allocated. The energy efficiency and slot utilization of the I-MAC protocol are higher than 802.15.4, and can satisfy the data delay requirement at the same time. When the amount of randomized medical monitoring data in each interrupt cycle is less than 1, the I-MAC protocol can significantly improve the performance of wireless body area network. For wireless body area network with low aperiodic random data, the protocol is also used. (3) The mechanism of key agreement based on noisy physiological signals in body area network is studied systematically and deeply. The advantages and disadvantages of two main key agreement technologies, Fuzzy Commitment and Fuzzy Vault, are analyzed in detail, and their respective characteristics are classified. The energy consumption of single-hop and multi-hop transmission modes is analyzed in detail. It is pointed out that single-hop transmission is more energy-efficient for body surface sensor nodes, which lays a foundation for constructing low-energy key management model of WAN. A lightweight MAC layer key agreement protocol based on Fuzzy Commitment and ECG signal is proposed. In the key agreement stage, the weak synchronization of noise physiological signals is realized by using time window mechanism, which avoids the huge energy consumption caused by precise time synchronization. Computational energy consumption replaces transmission energy consumption. Simple bit-level operation is used to avoid the protocol restart caused by the failure of key agreement caused by physiological signal noise, which greatly saves energy. On the basis of describing the research contents, a real-time medical monitoring system based on wireless body area network (WMAN) is constructed through detailed software and hardware design and key technology research. The system takes a variety of medical sensors as nodes and the designed intelligent cloud health detector as an intelligent coordinator. The rapid deployment of lightweight WBAN is realized. After intelligent processing, the data is uploaded to the cloud platform of medical monitoring in cloud computing center through adaptive heterogeneous network, which realizes intelligent analysis, processing, storage and display of medical data in cloud, and forms a closed loop of medical monitoring through mobile APP. Real-time detection, mobile query, remote monitoring and diagnosis functions, and through the complete test of ECG data, prove that relying on wireless body area network can effectively carry out remote real-time medical monitoring, with good application value.
【學(xué)位授予單位】：山東大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類號(hào)】：TN92
，

本文編號(hào)：2237119