Dynamic Signature System Calibration Device

TECHNOLOGY AREA(S): Air Platform
OBJECTIVE: Develop a calibration device for dynamic Radar Cross Section (RCS) measurements.
DESCRIPTION: The National Radar Cross Section Test Facility (NRTF) currently performs static RCS measurements from 60 MHz to 18 GHz and 34 GHz to 36 GHz. The NRTF needs a capability for performing dynamic (in-flight) RCS measurements from 2 GHz to 18 GHz, and possibly Ka band. Effective calibration is a crucial element in RCS metrology. Current dynamic calibration techniques include launching metallized calibration spheres through the test volume, trihedral reflectors, and active repeaters. These techniques can be costly and have a potential environmental impact. Use of a recoverable and reusable calibration device will improve reliability and repeatability of calibration measurements, while decreasing cost and environmental impact. The NRTF, as well as other dynamic test ranges, need recoverable and reusable calibration devices, however, other innovative calibration options that meet the minimal needs will be considered.
PHASE I: Perform a detailed Analysis of Alternatives (AoA) for suitable calibration devices for dynamic (in-flight) RCS measurement ranges, taking into account NRTF’s test environment, including atmospheric conditions. Demonstrate the feasibility of an approach that meets the stated criteria.
PHASE II: Design and develop a prototype calibration device and demonstrate the ability to use, recover and reuse the prototype calibration device at the NRTF, or other relevant facility.
PHASE III: Phase III efforts should extend the capability, as needed, mature the capability and produce units for other dynamic test ranges.
REFERENCES: 1. J. Ruoskanen, P. Eskelinen, H. Heikkila, P. Kuosmanen and T. Kiuru, "A practical millimeter-wave radar calibration target," in IEEE Antennas and Propagation Magazine, vol. 46, no. 2, pp. 94-97, April 2004.; 2. E. E. Martin, "Balloon Lofted Sphere as a Range Dependent Calibrated Target for Millimeter Wave Radar", Proc. SPIE 0791, Millimeter Wave Technology IV and RF Power Sources, (24 September 1987);KEYWORDS: Dynamic Measurement, Radar Calibration, RCS