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Time Difference of Arrival System for Cell Phone Localization in Correctional Facilities

NCJ Number
Date Published
May 2015
72 pages
This cell phone tracking project for use by correctional facilities developed hardware and software, completed the design of portable hardware, made progress toward the integration of the hardware components, and filed a patent to protect the intellectual property developed by the project.
The product and patent involved a novel technique for locating cell-phone use in an indoor environment. A hardware instrument and software package have been developed to implement the technique. A database that contains representative cell-phone signals for indoor environments has been established. Extensive testing was done on the system, which is called Tartarus. On the software side, the project examined the use of a classification-type approach to locating cell phones in prison. Extensive data were collected and analyzed, with encouraging results. These data were collected to train and optimize the detection and localization algorithms. The data were also used in an analysis that estimated the maximum coverage area that could be achieved with the current hardware. Future work will involve performing extensive experiments in outdoor environments using existing hardware. Demonstrations will be performed in a prison environment. There will be integration of the BPFs for three bands, so the user does not need to switch bands manually. The system hardware and software will be redesigned to make it more affordable, and the LTE band will be explored with a view toward covering LTE cell-phone signals. 51 figures and 3 tables

Date Published: May 1, 2015