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In a Defense and Technology Paper (DTP) entitled "A Methodology for Assessing the Military Benefits of Science and Technology Investments," the National Defense University (NDU) Center for Technology and National Security Policy (CTNSP) presented a variety of approaches for deriving the return on investment--in terms of warfighting capabilities---for Army science and technology (S&T) efforts. As a follow-up to the methodology study that generated the DTP, the CTNSP wished to demonstrate parts of the methodology in the evaluation of an actual Army S&T effort. The Army Research Laboratory's (ARL's) Micro-Autonomous Systems and Technology (MAST) Collaborative Technology Alliance (CTA)2 program was chosen to demonstrate the utility of the methodology because it offers significant future capabilities for our Army, provides a set of very robust present-day technical challenges, and offers a significant assessment challenge since it is focused on basic research.

A research effort was conducted to explore the ways in which sub-wavelength gratings can be used to reduce the reflections from the optics of millimeter-wave imaging systems. A moth-eye lens is sometimes used at optical and infrared frequencies for this purpose, but it is too fragile to be applied directly to the plastic lenses used in the millimeter-wave. A modification of this structure, called the inverse moth-eye lens, was designed, fabricated, and tested. Within the report we present results at 35 GHz showing a 15-dB reduction of surface reflections in Rexolite. The technique was also applied to a material with a dielectric constant of 9. Transmission increased an average of about 30 dB between 30 and 40 GHz with the inverse motheye, anti-reflection (AR) surface. The implication of these results is that the weight and bulk of millimeter-wave imaging systems could be significantly reduced by using optical systems with high dielectric materials and etched, sub-wavelength AR surfaces.

Most improvements in radar have concentrated solely on the temporal characteristics of the electromagnetic pulse. The spatial dimension is typically exploited only through arrays of antennas. The limits to using spatial characteristics of a transmitted beam to perform ranging were investigated, specifically, Laguerre-Gaussian beams as potential carriers for encoding range in spatial characteristics. The results indicate that whereas the beams are indeed capable of encoding range, aberrations and imaging fidelity limit the utility of the approach to small ranges. The system is better suited for microscopy than it is for battlefield ranging.

Army transformation is an attempt to provide future forces with enhanced capabilities in lethality, survivability, and mobility, both strategic and tactical. Alternatives to achieving these goals differ in emphasis on weight and reliance on technology. That is, transformation plans differ if the objective is weight reduction as opposed to weight redistribution. in one approach, platform weight is reduced to meet mobility goals. However, shedding weight has implications for platform survivability and lethality; previous attempt to design a single platform that is simultaneously lethal, mobile, and survivable have not done so satisfactorily. Thus, advances in materials are required to insure the survivability of a lightweight platform. Advances in network technology are also required to make the platform more aware of its environment.