Airborne Ground Penetrating Imaging Radar Operating at L-Band

The FOPEN radar was designed and fabricated in response to the need to detect items buried below the surface using a rapid detection method from an airborne platform. The system uses Synthetic Aperture Radar Processing in the form of ratcheting spot light SAR. The image of the ground at a slant range of 40 degrees on either the right or left side of the aircraft and gives a two dimensional image of the ground. The antenna can also point in a nadir position to sound the ground. The radar was developed to image 1 sq mile with each frame with a resolution of 1 meter in the slant range. This requires the use of the entire L-Band radar spectrum of 150 Meg Hz. In order to detect images below the ground additional processing must be performed on the raw data, accordingly the raw data is recorded at a data rate of 200 Mbyte/second. The data is recorded as both I and Q data. The radar has on board processing but only for verifying that the system is operating. Not all adjacent frames are processed for this reason. The processing and analysis is performed on the ground by a system that has multiple work stations and software to process the image of the surface and the sub surface. By further processing the data the surface can be removed and the lower level glint points can be seen and enhanced using signal processing techniques(1).