基于CSS的高精度室内定位技术研究与实现

发布时间：2018-03-06 19:41

本文选题：室内定位　切入点：高精度　出处：《湖南大学》2013年硕士论文　论文类型：学位论文

【摘要】：普适计算力图将以计算机为中心的计算模式转变为以人为中心的计算模式,其目标是构建一个计算和通信无处不在的环境,并在此基础上透明地提供以人为中心的服务。获取物体的位置信息是实现普适计算的关键环节,全球定位系统(Global Positioning System, GPS)可以实现普适计算条件下物体位置信息的获取,但在室内环境下GPS的定位精度降低,达不到普适计算要求。因此,研究一种适合于室内环境的定位系统有重要的理论和现实意义。现有的定位系统各有优劣,其中定位精度比较高的系统存在信号带宽过宽、成本较高的问题,而定位精度比较低的系统存在不够精确、不够稳定的问题。本文在分析多种定位系统技术的基础上,采用线性调频扩频(Chirp Spread Spectrum, CSS)的高精度室内定位方法。针对定位过程出现的信号碰撞问题,以及初始估算坐标精度不高的问题,提出了相应解决方案,所完成的工作如下： (1)通过分析两类经典防碰撞算法,并借鉴动态帧时隙防碰撞算法(Dynamic Frame Slot Aloha, DFSA),提出了一种确认动态帧时隙的防碰撞算法(Acknowledge Dynamic Frame Slot Aloha, ADFSA)。ADFSA算法继承DFSA算法的动态调整帧时隙的原理,并且利用历史帧识别信息来决定标签向哪个时隙发送数据,减少了标签随机发送数据的情况。实验表明,所提出的ADFSA算法的吞吐率相对于以前算法有明显的提高。 (2)针对智能家居定位场景需要高精度定位的特点,为克服室内环境对定位精度造成的不利影响,本文提出了结合三边测量定位的加权校正定位算法。定位系统首先利用三边测量定位算法估算出标签的初始位置,然后利用初步定位得到的待测标签与参考标签的位置信息来确定待测标签与参考标签的近邻程度,并结合参考标签的估算坐标与实际坐标间的误差,来校正待测标签的初始估算坐标,从而提高定位精度。 (3)基于现有硬件设备以及提出的加权校正定位算法,设计开发了一个定位系统原型,实现了基于CSS的高精度室内定位方法,平均定位精度达到0.8890米,基本普适计算定位要求。以上工作表明本文所采用的基于CSS的高精度室内定位方法是可行的,能提供一种成本较低,基本满足普适计算精度要求的室内定位解决方案。
[Abstract]:Pervasive computing seeks to transform computer-centric computing into human-centred computing, with the goal of building a ubiquitous environment for computing and communication. On the basis of this, we can provide the human-centered service transparently. Obtaining the position information of objects is the key link to realize universal computing. GPS (Global Positioning system) can obtain the position information of objects under the condition of pervasive computing. However, the positioning accuracy of GPS in indoor environment is low, which can not meet the requirements of universal computing. Therefore, it is of great theoretical and practical significance to study a positioning system suitable for indoor environment. The existing positioning system has its own advantages and disadvantages, among which the system with high positioning accuracy has the problems of wide signal bandwidth and high cost, while the system with low positioning accuracy is not accurate enough. Based on the analysis of various positioning system technologies, the high precision indoor positioning method of Chirp Spread Spectrum (CSS) is adopted in this paper. And the problem that the precision of the initial estimation coordinate is not high, the corresponding solution is put forward. The work accomplished is as follows:. 1) by analyzing two kinds of classical anti-collision algorithms and using dynamic Frame Slot Aloha, DFSAA algorithm for reference, a collision prevention algorithm for confirming dynamic frame slot is presented. The ADFSA).ADFSA algorithm inherits the principle of dynamic frame slot adjustment based on DFSA algorithm. The history frame identification information is used to determine which time slot the label sends data, which reduces the random transmission of data. The experimental results show that the throughput of the proposed ADFSA algorithm is significantly higher than that of the previous algorithm. 2) in order to overcome the adverse influence of indoor environment on positioning accuracy, aiming at the characteristics of high precision positioning in smart home positioning scene, In this paper, a weighted correction localization algorithm is proposed, which combines with triangulation and positioning. Firstly, the initial position of the label is estimated by using the triangulation localization algorithm in the positioning system. Then, using the position information of the tag to be tested and the reference label, the nearest neighbor degree of the tag to be tested and the reference label is determined, and the error between the estimated coordinate and the actual coordinate of the reference label is combined. To correct the initial estimated coordinates of the tag to be tested, so as to improve the positioning accuracy. Based on the existing hardware equipment and the weighted correction algorithm, a prototype of the positioning system is designed and developed. The high precision indoor positioning method based on CSS is realized. The average positioning accuracy is 0.8890m. The above work shows that the high precision indoor positioning method based on CSS is feasible and can provide a low cost indoor positioning solution that can basically meet the requirements of universal computing accuracy.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P228.4

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