This paper presents calibrated radar cross section (RCS) data of various objects considered to be a hazard for a landing helicopter and a technique for extracting these values from inverse synthetic aperture radar (ISAR) imagery. Data was collected at an outdoor facility using a fully polarimetric, 94-GHz radar mounted on an elevator that was positioned on a 125-foot tower to collect data at various depression angles. Targets were placed on a 22-foot diameter turntable and rotated a full 360 degrees to form ISAR imagery at all aspect angles. The technique being described was formulated to enable the extraction of objects of interest from the imagery. In order to calculate accurate RCS data of each object on the turntable, an area within the ISAR image was assigned to each object for every image formed during a full rotation. This area was tracked as it traveled 360 degrees enabling the generation of polar plots of RCS. This was done at multiple depression angles to capture the linear co- and cross-polarized signatures. The measured objects include a large metal cube, a chain link fence and a 1.5-in, diameter wound-metal cable.

With the changing nature of international security it is of interest to the military to use remote sensors to detect and classify people as potential threats. We chose a millimeter wave (MMW) radar as our sensor to collect data on single and small groups of people that were either walking or running to determine how easily they could be detected. This work was done to support the concept of using Ka-band radar to detect people from an airborne platform. Fully-polarimetric Ka-Band radar data was collected of people walking and running at various orientations with respect to the radar. Micro-Doppler analysis reveals Doppler oscillations with time that are characteristic of people at all orientations measured.

: Collecting high resolution radar imagery of ground vehicles is of interest to many Army and DOD agencies. Systems used to acquire this data rely on high quality calibration data to produce meaningful radar images. A system to collect high resolution radar data has been built at the U.S. Army Research Laboratory. A method to quickly and accurately collect the calibration data needed by this system, an inverse synthetic aperture radar (ISAR), is presented in this report.