The proposed Phase I research will define and evaluate the technical feasibility of a novel concept for selectively denying the use of GPS by adversaries. The goal is to provide mobile military units a flexible GPS denial system that can operate both autonomously and in a coordinated, network-centric, manner. Termed the GPS Selective Denial System (SDS), the proposed concept will equip mobile units with the capability to target specific regions and/or adversaries, denying them the use of GPS while still enabling our own forces continued service. The SDS is a fully programmable, beam steerable, jamming system that utilizes a high-quality frequency reference and monitoring of the GPS to produce a variety of jamming signals designed to disrupt an adversarys GPS service. At the same time, receivers equipped with the appropriate anti-jam components (termed the SDS Decoder) and apriori knowledge of the jamming scenario can effectively eliminate the jam, enabling normal operation without major degradation. The proposed research will develop this concept in accordance with known requirements in preparation for a Phase II implementation. Research will consist of theoretical analysis, requirements analysis, systems design, and simulation testing. Feasibility will be assessed by analyzing expected performance, complexity, production costs and anticipated benefits.
Benefits: The proposed research seeks to define new methods in GPS selective denial technology by incorporating a precision frequency reference, knowledge of location and a fully programmable, L-band signal synthesizer that generate signals that exploit specific weaknesses in the GPS C/A and P(Y) signal structures. With this technology, users have complete control over the amplitude, frequency, phase, and beam characteristics, enabling the device to support a wide variety of jamming scenarios and configurations. The resulting system will be flexible, portable, relatively low-cost to manufacture, and has provisions to retrofit existing military receivers at a minimum expense. The concept can also be applied to other positioning systems and communication (broadband or narrowband) systems as well. This includes GLONASS, the forthcoming Galileo, and a variety of cellular communications (for example TDMA / CDMA based cellular systems). Lastly, when used in a coordinated mode, the SDS can operate simultaneously as both a jammer and pseudolite system.
Keywords: GPS, Jamming, Selective Denial, Anti-Jam, Net Centric, GPS Vulnerability, Precision Guidance and Navigation, electronic warfare
