WPI Precision Personnel Locator System -Indoor Location Demonstrations and RF Design Improvements

摘要

This paper describes the latest developments in the Worcester Polytechnic Institute (WPI) Precision Personnel Locator (PPL) project The RF-based PPL system is being developed for tracking of first responders and other personnel in indoor environments. The system assumes no existing infrastructure, no pre-characterization of the area of operation and is designed for spectral compliance. This paper concentrates on describing the effects of different bandwidths on tracking and location accuracy in a variety of building structures based upon tests of the full system in those environments. The paper also documents the results of substantial improvements in the location algorithm. Recent testing has shown sub-meter positioning accuracy of a transmitter even in difficult indoor environments with high multi-path despite all receivers being placed outside the building. The current system has demonstrated accuracies of approximately 0.5m in real building environments. Results to date have been achieved with a 60 MHz wide multi-carrier signal from 410 to 470 MHz. The RF transmitter and receiver hardware are currently being upgraded to allow operation in the 550 to 700 MHz region. A description and initial bench tests of the new RF hardware are included.