GPS-denied Positioning using Networked communications

ABSTRACT: A robust back-up navigation alternative is needed to continue to provide accurate PVT data when GPS is denied. Navigation solutions can be enhanced by utilizing existing networked communications for dismounted forces operating in small platoons. When some of the forces lose their GPS signals, traditional GPS-denied network positioning techniques such as Time of Arrival (TOA) or Time Difference of Arrival (TDOA) have been employed previously. Unfortunately these techniques require extremely tight time synchronization among the sensor nodes; and such a synchronization requirement has previously been too stringent to be reasonably met by man-portable hardware due to SWaP constraints. This effort will evaluate methods to allow use of RF ranging through TOA and signals of opportunity (SoOP) through TDOA, by leveraging high precision time transfer between software defined radios to maintain the tight time synchronization needed to perform back-up navigation in a GPS denied environment. The expected performance will be demonstrated through simulation and prototyping efforts. A plan shall be developed to perform a sub-scale demonstration of a positioning network in Phase II to demonstrating the ability of a group of nodes to successfully navigate under GPS-denied conditions and evaluate transition options for operational SDR products. BENEFIT: The NAVSYS DiNO-Pos (Distributed Network Opportunistic Positioning) technology will achieve high positional accuracy in GPS-denied environments that will increase military operational effectiveness and save lives. The civilian public protectors will also be able to execute their tasks more efficiently and with less delays that can also save lives. Private sector applications include automobile navigation and fleet/asset management where operational integrity can be preserved during these adverse conditions.