【作者】 陈雯柏；

【导师】 张小频；

【作者基本信息】 北京邮电大学 ， 电磁场与微波技术， 2011， 博士

【摘要】 无线传感器网络综合了传感、无线通信、分布式信息处理及嵌入式系统等相关技术,可以在任何地点、任何时间及任何环境条件下,通过传感器节点终端进行数据采集和处理,获取大量可靠详实的信息。将下一代移动通信系统关键技术——MIMO技术引入无线传感器网络,可利用MIMO技术提供的分集增益性能来克服信道衰落；亦可利用MIMO技术带来的复用增益性能来提高信息速率。这两方面均有利于提高传感器网络的能效。基于MIMO技术的无线传感器网络成为一个新的研究热点。由于移动机器人机动灵活与自治能力,将机器人技术引入无线传感器网络,可以很方便地改变无线传感器网络的拓扑结构和改善网络的动态性能,在民用、军事和航空领域均有非常广阔的应用前景。联系构成事物的运动,而事物间的联系也离不开运动。通信和运动构成了我们生活着的这个世界的两个重要的问题。本文针对无线传感器网络,提出了通信与移动这两个基本命题,对无线传感器网络中虚拟MIMO通信与移动机器人控制的相关算法进行了一定研究,其主要内容如下：(1)对无线传感器网络中虚拟MIMO通信的基于V-BLAST接收的信号检测算法进行了较为深入的研究。高BER性能、低复杂度的V-BLAST接收信号检测算法的研究与设计对无线传感器网络的节能传输具有重要意义。本文在V-BLAST接收的基本检测算法研究的基础上,提出了迭代V-BLAST检测、迭代QR检测与最大似然检测算法的4种低复杂度的改进算法,分析了其复杂度并进行了仿真实验。仿真结果表明提出的改进算法在检测性能和算法复杂度方面取得了良好的平衡。(2)对无线传感器网络中基于移动机器人V-BLAST的接收技术进行了研究。有效地抑制多径衰落是无线传感器网络实用化的关键之一。MIMO技术引入无线传感器网络,有利于克服信道衰落、提高信息速率,从而改善网络的能效特性与连通特性,这将极大地延长传感器网络的生命期。本文在研究分析无线传感器网络能效策略与协作式MIMO技术的基础上,提出基于机器人的无线传感器网络V-BLAST的接收方案。根据应用场合的不同,移动机器人可担任汇聚节点也可担任中继节点实现V-BLAST接收。移动机器人节点可以自带多天线接收或单天线接收,文中对每种方案的能耗进行了分析,并采用本文提出的低复杂度近似最大似然检测算法进行了仿真研究。仿真结果表明,基于机器人的V-BLAST的接收方案与低复杂度的近似最大似然检测算法的采用有效地提高了网络能效。(3)对移动机器人基于混沌机制的相关控制算法进行了研究。机器人的移动能力取决于其运动系统,运动控制系统的性能好坏与控制算法有很大关系。本文针对两轮差动式移动机器人的运动控制提出变尺度混沌参数优化PID控制策略并给出了仿真结果；针对机器人控制研究领域中复杂被控对象——倒立摆系统提出基于混沌优化的神经网络控制方法,进行了一级倒立摆系统优化的比较研究,对于二级倒立摆系统实现实时稳定控制。实验的成功说明控制算法是有效的,可应用于移动机器人,提高移动机器人运动控制系统的性能,并进一步提升移动机器人的整体性能。更多还原

【Abstract】 Wireless sensor networks (WSN) combine sensor technology, wireless communication technology, distributed information processing technology and embedded computing technology, so that people can obtain large amounts of detailed and reliable information at any time, any place and any environmental conditions through data acquisition and processing of sensor nodes.Introducing the key technology of next generation mobile communication systems Multiple-input Multiple-output (MIMO) technology into WSN can make use of the diversity gain to overcome fading effects and make use of the multiplexing gain to improve the information transfer rate, thus to greatly improve energy-efficiency of the network. As MIMO-based WSN has become a new hotspot and mobile robot has the capabilities of being flexible and autonomous, introducing the robot technology into wireless sensor networks can easily change the topology of wireless sensor networks and improve the dynamic performance of the network, which has very broad prospects in civil, military and aerospace applications.In philosophical sense, communication and mobility are two important issues which constitute the world we live in. Aiming at wireless sensor networks, this paper boldly put forward two basic propositions, communications and mobility. A research has been made on related algorithms about the virtual MIMO communication and mobile robot control in wireless sensor networks. Its main contents are as follows:(1) Propose 4 novel efficient decoding algorithms for V-BLAST detection.An in-depth study has been made on decoding algorithms for V-BLAST detection in MIMO-based WSN. The decoding algorithm with high BER performance and low complexity for V-BLAST detection has great significance for energy-efficiency in WSN. Based on the study of basic V-BLAST detection, iterative V-BLAST detection and iterative QR detection,4 kinds of improved algorithms with low computational complexity are proposed. Simulation results show that the improved algorithm has achieved a good balance between detection performance and complexity(2) Propose a novel mobile robot & V-BLAST based cooperative MIMO transmission scheme in WSN.A study has been made on the mobile robot & V-BLAST based cooperative MIMO transmission technology in WSN. To effectively suppress multi-path fading in WSN is one key in WSN practicalization. MIMO-based WSN can use its diversity gain to overcome fading effects and can also use its multiplexing gain to increase the data transmission rate, thus to greatly improve the network’s energy-efficiency and connectivity features, thereby, the network’s life cycle can be prolonged.’After the study on the energy-efficiency strategies of WSN and cooperative MIMO transmission technology, mobile robot & V-BLAST based cooperative MIMO transmission scheme are proposed. According to different applications, mobile robots can act as the sink node or relay nodes to achieve V-BLAST based cooperative MIMO transmission. Mobile robot node can own multi-antenna or one antenna in this scheme. The energy consumption of each program is analyzed in this paper, and the proposed low-complexity maximum likelihood detection algorithm is used to decode the cooperative MIMO transmission. Simulation results show that the adoption of the program is effective and the low-complexity maximum likelihood detection algorithm further improve energy-efficiency.(3) Propose a novel chaos optimization method for mobile robot control.A study has been made on the control algorithm of the mobile robot system based on chaos optimization. The robot’s mobility depends on its motion system, and the control algorithm is the key to the performance of motion control system. A PID controller is designed for mobile robot, and the parameters of the controller are optimized by chaos method. For inverted pendulum system, the complex controlled object in the field of robot control, a neural network control method on the basis of chaos optimization is proposed and real-time control of double inverted pendulum has been successfully achieved. Success of the experiment shows that the control algorithm is effective and can be applied to mobile robots to improve the performance of mobile robot motion control system and to further enhance the overall performance of mobile robot.更多还原