基于可见光通信的隧道车辆定位系统设计

发布时间：2019-04-12 14:03

【摘要】：随着我国公路建设步伐的进一步加快,特别是山区高速公路的发展,其催生的隧道数量急剧增长。由于隧道具有内部空间狭小、结构复杂、封闭性强等特点,导致GPS系统在隧道内部失去定位功能,给汽车的安全、平稳行驶航带来了一定的阻碍。因此需要一种不依靠GPS信号来实现隧道车辆定位的新技术。在现有的以Wi-Fi、蓝牙、ZigBee为代表的等其他短距离无线定位技术精度较低、无线频谱资源消耗严重、工程实施成本高、系统布局复杂的背景下,可见光定位技术作为可见光通信技术主要应用之一,其充分利用现有照明设施的同时,还可以获取较高的定位精度。本课题以实验室项目为依托,主要从隧道可见光通信信道特性研究、通信节点设计、定位算法三个方面对基于可见光通信的隧道车辆定位系统进行研究。首先,从LED的特性入手,分别对LED的发光原理、电气及光学特性和发光辐射模型进行详细的阐述。结合隧道的实际环境分析了可见光通信链路,并利用Matlab对光源布局进行设计仿真,使其光照区域平均亮度达到系统的照明和通信需求。然后,根据系统需求设计了锚节点和移动采集节点硬件电路的设计,锚节点可实现在不影响正常照明的前提下可将数据信息以光的形式发送出去;移动采集节点实现对光信号的采集并通过放大得到RSS信号和通过整形还原出数据信息。同时,基于FPGA开发模块实现了系统的通信,控制单元软件的设计。最后,提出并实现了基于三边定位的可见光定位算法的设计。在离线建模阶段对接收到的RSS信号进行拟合得出“RSS-距离”经验公式;在线定位阶段首先经过评估筛选出3组RSS数据,然后结合“RSS-距离”经验公式和采用最大似然估计的三边定位算法得出最终定位结果。
[Abstract]:With the speeding up of highway construction in our country, especially the development of highway in mountain area, the number of tunnels is increasing rapidly. Because the tunnel has the characteristics of narrow internal space, complex structure and strong sealing, the GPS system has lost its positioning function in the tunnel interior, which has brought some obstacles to the safety and smooth navigation of the automobile. Therefore, we need a new technology that does not rely on GPS signal to realize vehicle positioning in tunnel. In the existing Wi-Fi, Bluetooth, ZigBee and other short-range wireless positioning technology, such as low precision, serious consumption of wireless spectrum resources, high cost of implementation of the project, and the complex layout of the system, As one of the main applications of visible light communication technology, visible light positioning technology can make full use of the existing lighting facilities, and it can also obtain high positioning accuracy. Based on the laboratory project, this paper mainly studies the tunnel vehicle positioning system based on visible light communication from three aspects: the characteristic research of tunnel visible light communication channel, the design of communication node, and the positioning algorithm. Firstly, based on the characteristics of LED, the luminescence principle, electrical and optical characteristics and emission model of LED are described in detail. According to the actual environment of the tunnel, the visible light communication link is analyzed, and the layout of the light source is designed and simulated by using Matlab, so that the average luminance of the illumination area can meet the lighting and communication requirements of the system. Then, according to the requirements of the system, the hardware circuits of anchor node and mobile acquisition node are designed. The anchor node can transmit the data information in the form of light without affecting the normal lighting. The mobile acquisition node acquires the optical signal, amplifies the RSS signal and restores the data information by shaping. At the same time, the communication of the system and the design of the control unit software are realized based on the FPGA module. Finally, the design of visible light location algorithm based on trilateral localization is proposed and implemented. The "RSS- distance" empirical formula is obtained by fitting the received RSS signal in the off-line modeling phase. In the stage of on-line localization, three groups of RSS data are selected by evaluation, then the final localization results are obtained by combining the empirical formula of "RSS- distance" and the trilateral localization algorithm based on maximum likelihood estimation.
【学位授予单位】：江苏理工学院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN929.1;U495

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