【作者】 徐伟；

【导师】 刘守印；

【作者基本信息】 华中师范大学 ， 通信与信息系统， 2014， 硕士

【摘要】 室内定位是指当人或者物体在室内时,获取其位置信息的定位技术。由于GPS(Global Positioning System)全球定位系统在全世界的普及,室外定位技术已经非常成熟,但是,在室内接收的GPS信号非常微弱,甚至接收不到,故室内定位需要采用新技术。目前,可用于室内定位的技术有很多,包括RFID、蓝牙、红外、UWB、 ZigBee、WiFi和行人航迹推算PDR(Pedestrian Dead Reckoning)技术等。行人航迹推算PDR技术是一种基于传感器信息计算行人相对位置的定位技术,它首先通过加速度传感器检测行人的步数并估算出步长,然后通过磁阻传感器和陀螺仪计算出行人的方位角,最后获取人体移动的相对位置从而实现定位。相较于其他室内定位方法,行人航迹推算PDR不受外界环境影响,定位精度较高,但只能获取相对位置信息,且存在累积误差；而WiFi定位是基于设备接收到的WiFi热点的信号强度,来计算物体的位置信息,因此通过WiFi定位可获取绝对位置信息,可用来减小PDR定位累积误差,但是WiFi定位精度易受外界环境的影响。因此本文使用行人航迹推算PDR和WiFi联合定位技术,实现高精度和高稳定性的室内定位。此外,由于WiFi热点已经广泛存在于室内空间,因此此种联合定位方式一般不需要额外布置其他硬件设备。现在,智能手机越来越普及,WiFi成了必备功能,大多数智能手机也内置了加速度传感器和磁阻传感器,少数手机还内置了陀螺仪和气压计,因此直接使用智能手机实现室内定位成为了研究热点。本文以Android智能手机XIAOMI M1作为硬件平台,设计并实现了行人航迹推算PDR和WiFi联合室内定位系统。首先,在Android手机上设计并实现WiFi室内定位；然后,基于Android手机平台设计并实现行人航迹推算PDR技术,并提出新的步长估计算法以提高定位精度；最后,提出行人航迹推算PDR和WiFi联合室内定位技术的融合策略,并用实验验证。本文主要研究的内容和实现的工作有：(1)在WiFi网络基础上,研究和设计了基于Android手机平台的室内定位技术,并搭建基于WiFi定位的服务器；(2)研究和实现了基于Android平台的行人航迹推算PDR技术；(3)提出新的步长估计算法,并设计实验验证其提高了步长估算的精度；(4)提出行人航迹推算PDR和WiFi联合的室内定位技术的融合策略,并设计实验验证。更多还原

【Abstract】 The indoor positioning means obtaining the position information of a person or an object in a room. Due to the popularity of the GPS, the outdoor localization technology is fully developed. But in the indoor condition, the GPS signal is too weak to be detected, so indoor positioning needs new technologies. At present, RFID, Bluetooth, Infrared, UWB, ZigBee, WiFi and PDR (Pedestrian Dead Reckoning) and many other techniques have been used in this area. PDR is a technology using sensor information to calculate the relative position. Firstly, it detects the steps and estimates the step length of a pedestrian using the accelerometer. Then it utilizes the gyroscope and the electronic compass to calculate the azimuth. Finally it obtains the relative position of the pedestrian. Compared with other indoor positioning techniques, PDR has higher positioning accuracy and it won’t be affected by the environment. However, it can only obtain the relative position information and has cumulative errors; While WIFI positioning is based on the receiving signal strength from the AP (Access Point), so it can give the absolute position information and help reduce the PDR positioning cumulative error, but the positioning accuracy depends on the environment. Therefore, this article proposes a fusion strategy of PDR and WIFI positioning technologies to achieve high accuracy and stability indoor localization. In addition, as APs widely exist in the room, it is easy to realize PDR and WIFI positioning without adding additional hardware equipments.As the smart phones become more and more popular, and they were embedded with WiFi module, accelerometer, electronic compass and gyroscope, the research and implementation of indoor positioning based on the android mobile phone has become a hotspot. This paper chooses XIAOMI M1as hardware platform to implement the indoor positioning system. Firstly, this paper describes how to achieve indoor positioning system based on WiFi. Then, it describes indoor positioning system based on PDR, and puts forward a new step length estimation algorithm to improve the positioning accuracy. Finally, this paper puts forward a fusion strategy for indoor positioning based on PDR and WiFi technologies.The main contents and results of the research in this paper are as follows:(1) Researching and designing the indoor positioning system based on WiFi, and setting up the WiFi indoor positioning server. (2) Researching and designing the indoor positioning system based on PDR.(3) Putting forward a new step length estimation algorithm to improve the positioning accuracy.(4) Putting forward a fusion strategy for indoor positioning based on PDR and WiFi.更多还原