SBIR Phase I: High Resolution Channel Sounding for Indoor TDOA Positioning Using Narrowband RF Transceiver

这个小型企业创新研究第一阶段项目的重点是无线到达时间差（TDOA）定位技术的室内或杂乱的室外环境。 室内TDOA技术迄今为止几乎没有商业上的成功，主要是因为多径信号反射离开表面，其涂抹空中信号的到达时间，使得难以确定从视线或最短距离路径的位置信标的到达时间。宽信号带宽增加了时域中的分辨率，允许接收器区分路径。使用如此宽的信号带宽的一个关键挑战是，它可以？不能用商业上可获得的高度集成的低成本组件来完成。另一个约束是限制这种信号的发射功率的监管限制。本研究的重点是开发一种方法来克服这些实际的限制，通过定义一种特殊类型的窄带定位信标，提供相同的性能非常宽带信号，但可以使用负担得起的，现成的无线电组件来实现。大量的应用可以从高分辨率室内定位技术中受益，包括：智能手机的室内楼层地图定位和路线指引、室内基于位置的广告、室内E911、基于位置的安全、医务人员和资产监控以及搜索和救援。 然而，现有的解决方案，如最近的接入点或接收信号强度三角测量，既不够准确，也不符合成本效益，因为需要高密度来实现这一精度。存在基于超宽带的TDOA解决方案，其具有更好的精度，但是这些网络由于FCC功率限制和迄今为止有限的市场成功而具有有限的范围。WiFi已经彻底改变了无线移动性，这里介绍的解决方案将利用WiFi作为进入市场的战略。 如果成功，该解决方案将不受监管权力限制的限制，并且由于它基于WiFi，因此价格实惠。

This Small Business Innovation Research Phase I project is focused on wireless Time Difference Of Arrival (TDOA) positioning technology for indoor or cluttered outdoor environments. Indoor TDOA technologies have had little commercial success to date primarily because of multipath - signal reflections off of surfaces that smear the arrival time of the over-the-air signals, making it difficult to determine the arrival time of the location beacon from the Line-Of-Sight or shortest distance path. The best way to combat multipath is to use very wideband beacon signals. The wide signal bandwidth increases the resolution in the time-domain, allowing the receiver to distinguish between paths. A key challenge with using such wide signal bandwidths is that it can?t be done with commercially-available highly-integrated low-cost components. Another constraint is regulatory restrictions that limit the transmit power of such signals. The focus of this research is to develop a way to overcome these practical limitations by defining a special type of narrowband location beacon that gives the same performance as very wideband signals but that can be implemented using affordable, off-the-shelf radio components. A great number of applications could benefit from high-resolution indoor location technology, including: Indoor floor map positioning and route guidance for smartphones, indoor location-based advertising, indoor E911, location-based security, medical staff and asset monitoring and Search and rescue. However, existing solutions such as nearest Access Point or Received Signal Strength triangulation are neither accurate enough nor cost-effective due to the high density required to achieve this accuracy. There are TDOA solutions based on Ultra WideBand that have better accuracy but these networks have limited range due to FCC power limitations and limited market success to date. WiFi has already revolutionized wireless mobility and the solution presented here will leverage WiFi as a go-to-market strategy. If successful, the solution will not be limited by regulatory power restrictions and will, because it is based on WiFi, be affordable.