RASAR ProgramReal-time Autonomous Synthetic Aperture Radar

Objective: • Develop a <25 lb podded quad-pol L-band synthetic aperture radar

(SAR) capability for Shadow-200 or similar platform• Tx, Rx, image formation and exploitation performed in pod

• Expand SRP architecture to include RF imaging• L-band day/night all weather imaging; X-band extension in FY12• Transition technology to STUAS beginning in FY12

Value to Naval Warfighter: • Tactical SAR mission support • Real-time-rate image formation both from ground and airborne

processors• CIED-specific image processing and detection capability

The Technology: • Digital, module-based, RF collection and pre-processing system• Wide-beam operation for multi-look image enhancement,

persistent surveillance, and simplified system design• Quad-polarization RF data collection and airborne pre-processing• Support for automated change-detection CONOPs• Air+ground image formation enables back-projection processing

Similar/Related Projects: • Leverage SRP payload developmentTRL: Current: 5

Major Milestones• 3QFY11, Non-podded quad-pol configuration enters flight testing• 3QFY12, Full podded quad-pol configuration enters flight testing

Approach: • Direct digital Tx & Rx system to collect and store full digital RF

waveform for ground post-processing• Airborne digital spotlighting to reduce RF data volume and enable

pulse data transmission across standard 10.71 CDL datalink• Enable real-time rate airborne image formation (up to 512 x 512

pixels) and transmission to disadvantaged forward user

LRIP Cost Estimate: • $400k for complete RASAR system including RASAR cards, SRP

chassis, pod and ground image exploitation computers

Current Program Plans: • X-band SAR modifications to be completed 4QFY12• STUAS system hardware migration to begin 1Q FY13

POC: Dr. Thomas J. Walls, Dr. Michael L. Wilson; Naval Research Laboratory

RASAR Program Overview

• RASAR: Real-time Autonomous Synthetic Aperture Radar– Enhances SRP Open Architecture to include a SAR

capability– Migrated from existing SAR system, NuSAR (NRL UAS

Synthetic Aperture Radar)• RASAR program goals:

– L-band capability • Day-night all-weather imaging• Optimize system performance in IED signature detection• Provides moderate foliage penetration capability • Mitigates UAS UHF antenna accommodation

and spectrum interference issues• Spectral sweet-spot for “WAB” operation

– Implement Wide Azimuth Beam (WAB) architecture• Demonstrated performance in counter IED mission• Enables multi-aperture image enhancement• Persistent surveillance and area survey operational modes• Simplified system design to meet UAS SWAP requirements

– Quad-polarization collection capability– Simultaneous HH/VV collection in podded configuration– Support change-detection (CD) CONOPs– Rapid add-on capability for existing theater assets

• Currently in flight testing L-band SAR, Urban SiteL-band SAR, Urban Site 2

Pod SWaP and Interfaces

• Pod developed and flight tested • Chassis developed and flight tested

• RASAR Pod– Dimensions: 8” diameter, 45” long– < 25 lbs weight-on-wing– 150 W average power consumption

• Interfaces– 28V power– Ethernet (for data link)

L-Band SAR Antenna

Electronics ChassisRam Air Scoop

GPS/INS

Wing Mounts

8” Diameter45” Length

Arbitrary waveform generation provides for a flexible band allocation

Primary frequency range Extended frequency range

1215 to 1390 MHz25 W peak power (<5 W average)

1110 to 1390 MHz25 W peak power (<5 W average)

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