TECHNOLOGY AREA(S): Materials
OBJECTIVE: To design, fabricate and demonstrate materials that can be effectively worn by the Soldier that reduce their signature and mitigate the detection of their movement from ground surveillance radar (GSR) threats in the battlefield.
DESCRIPTION: Radar absorbing and shielding technology has attracted a growing interest due to the recent advances in enemy electronic warfare and detection capabilities, leaving US forces, especially infantry forces, vulnerable to detection across the electromagnetic spectrum. Advanced Battlefield and Ground surveillance radar (BSR/GSR) are readily available in military markets that are highly effective, portable, and automated for large area monitoring. To counter these threats, studies of radar absorbing materials with proper thickness, cost, efficiency, weight, hardness/flexibility, stability and electromagnetic and physical compatibility are ongoing for protection in differing applications such as: navigation, aircraft technology, radio and electronic devices, and wireless systems (1). In military applications, electro-optics and electromagnetic features on textile substrates and fibrous materials play an important role in the ability to camouflage by muting Soldier movements on the battlefield (2). Stealth movement of infantry on the battlefield is a key priority for the military. This proposed call will focus specifically on Soldier signature management by altering/functionalizing clothing with radar absorbing materials to address ground surveillance radar threats by reducing Soldier signature. While there exists a wide variety of radar absorbing material (RAM) composites for shelters and vehicles (3), there are currently no effective and lightweight wearable options to mitigate GSR detection of a dismounted Soldier.
PHASE I: This phase of the program must show the feasibility of the technical approach through a demonstration of the preliminary designs ability to reduce the radar cross section of a characterized baseline material. The baseline material must be representative of current operational clothing and individual equipment systems (e.g. Soldier uniform, body armor, helmet, rucksack, etc.) The material must demonstrate successful performance in the X and Ku frequency bands. The feasibility assessment must include the scientific and technical rational for how the preliminary material will scale and perform effectively. It is not necessary to demonstrate the integration of the technology into a complete system, however, the planned technical approach and feasibility for system integration for Phase II must be included. Sample material must be delivered at the end of Phase I as well as a complete characterization of its mechanical properties, spectral absorbent effectiveness and design.
PHASE II: This phase will scale the successful Phase I technology into prototypes for lab and field based evaluations. Prototypes must demonstrate lab and field based capabilities within the X and Ku frequency bands at distances up to 12 km. Prototypes will range from a standardized 1 m2 test sample to representative operational clothing and/or operational equipment (e.g. body armor carrier, rucksack, etc.). The performance of the test samples and prototypes must be evaluated in laboratory and field settings and assessed in terms of radar cross section reduction, flexibility, durability, breathability and air permeability. The prototype materials must be tested and clearly demonstrate consistent functional properties under simulated operational use to include environmental factors such as a wide range of temperatures (-30 – 125ºF) and environmental factors (e.g. high humidity, rain, etc.) The final deliverable must also include a commercialization assessment and the viability of mass producing the developed technology.
PHASE III: This final phase will demonstrate the scalability, reliability, repeatability and operational application of the proposed technology. The technology developed under this effort has direct application to Soldier operational clothing and individual equipment. The results of this effort may culminate in the development a new material that could either replace standard materials used in uniforms, body armor carriers and rucksacks or integrate into the standard materials and substrates used in fielded systems.
1: Journal of Magnetism and Magnetic Materials, vol. 327, 151-158, 2013
2: Progress in electromagnetics research B. vol. 3, 219-226, 2008
3: Composite structures, 76, 397-405, 2006
KEYWORDS: Radar Absorbing Materials, Functional Textiles