Collaborative Research: EAGER: Novel Theoretical Foundation for Wireless Positioning in Challenging Environments

移动设备定位技术在许多社会、工业和军事活动中发挥着至关重要的作用。在目前的全球定位系统(GPS)中，三角测量和/或三边测量计算方法占主导地位，必须求解由四个或更多个卫星信号获得的由四个或更多个二次方程组成的系统。然而，这个系统在具有挑战性的环境中不起作用，比如市中心，那里的卫星信号被摩天大楼挡住了。这项工作是为了开发、分析和评估能够在定位精度和时间效率方面改善现有GPS的计算方法。本项目中提出的线性化方法的独特之处在于，它为GPS计算单元中的二次方程提供了一个封闭的解。对定位误差源进行了灵敏度分析。这样，GPS的性能就可以显著提高。此外，由于定位过程中的漏洞被识别，这项工作也是解决安全/隐私相关问题的有用工具。这项工作适用于其他无线环境，并可以与其他无线技术相结合，如WiFi和无线传感器网络(WSNs)。初步仿真结果表明，该算法的计算精度提高了30%，执行时间复杂度提高了50%。该项目开发的基本框架和稳健的定位技术将对高科技行业产生广泛影响。这项变革性的研究将导致新一代实用定位系统的开发和部署，这些系统可以在各种具有挑战性的环境中有效和高效地工作。该项目的影响还通过出版物和专门网站扩展到学术界和教育界。

Positioning techniques for mobile devices play critical roles in many societal, industrial, and military activities. In current Global Positioning System (GPS), the triangulation and/or trilateration calculation approach dominates, where a system of four or more quadratic equations must be solved, obtained from four or more satellite signals. However, this system does not work in challenging environments such as downtown areas where satellite signals are blocked by skyscrapers. This work is to develop, analyze and evaluate computational methods that can improve the current GPS in terms of positioning accuracy and time efficiency. The proposed linearization approach in this project is unique in that it provides a closed form solution for quadratic equations in the calculation unit of GPS. The sensitivity analysis is derived to identify positioning error sources. The performance of GPS can then be significantly improved. Additionally, since the vulnerabilities in the positioning procedure are identified, this work is also a useful tool for solving security/privacy related issues. This work is applicable to other wireless environments and can be incorporated with other wireless techniques, such as WiFi and wireless sensor networks (WSNs). Preliminary simulation results show that the performance of the proposed calculation method increases by 30% in terms of accuracy and 50% in terms of execution time complexity. The fundamental framework and robust positioning techniques developed from this project will have broad impacts on high-tech industries. The transformative research will lead to the development and deployment of a new generation of practical positioning systems that can work effectively and efficiently in various challenging environments. The impact of this project also extends to academia and education through publications and dedicated websites.