Extending the Surveillance Horizon for Improved Ship Self-Defense Against Hypersonic Cruise Missiles

HCMs pose a unique and challenging threat due to their speed, maneuverability, and low flight altitudes. They maneuver and change their trajectory while traveling at a much lower altitude as compared to their TBM counterparts as they only reach peak altitudes of 100 km in the upper atmosphere as opposed to 1400 km peak TBM’s and spend much of their flight time at significantly lower altitudes. This shortens the flight time from the ship’s horizon and timeline to intercept significantly.  This can be mitigated by employing MALE or HALE UAS to extend the horizon but still requires new radar modes. RDRTec proposes to expand our Challenging target Airborne Detection & Discrimination (CADD) mode development testbed to create a suite of tools for the development and evaluation of radar modes suitable for defense against HCMs.  CADD has been developed across a series of SBIR topics including: N141-067, N151-105, N152-083, N192-059, and N192-089.  It provides a means of developing and testing advanced radar modes suitable for challenging target detection and discrimination.  A series of different waveforms as a function of the sensor’s platform velocity tangential to the search direction must be employed.  Highest performance will be achieved where tangential velocity is sufficient to support Synthetic Aperture Radar (SAR) modes which will provide the best cross range resolution. Coherent techniques based on SAR processing are well suited to addressing the problem of detection and discrimination of hypersonic cruise missiles (HCM) despite the motion of the HCM during coherent integration time.  They provide wide area coverage and are far less sensitive to grazing angle than non-coherent techniques, allowing the platform to operate at higher altitudes and steeper grazing angles. In addition, they offer improved performance due to a richer set of potential discriminants and the ability to detect moving targets with a wide range of motion paths. Where only modest tangential velocities are available the mode will employ Doppler Beam Sharpening (DBS) techniques and when no limited tangential velocity is available the mode will resort to real beam waveforms.  In all three sectors, processing will take advantage of multiple apertures (STAP or monopulse) and multiple polarizations when available. The use of a multi-polarimetric data may improve detection and tracking of HCMs. However, the performance gains relative to single-pol systems have not yet been fully quantified. RDRTec proposes to attack this HCM topic in collaboration with a diverse, collaborative set of partners in order to view the problem from multiple points of view, leverage a broad range of expertise, and increase the likelihood of transitioning the results to the US war fighter.  This team is comprised of: RDRTec (research prime), HyPerComp (modeling experts), NRL (subject matter experts), and Telephonics (subject matter experts and supplier of radars to multiple USN programs).