AIL Systems Inc of Deer Park, New York designed and manufactured the US Army's AN/PPS-5 battlefield surveillance radar. In conjunction with the US Army's Modular Radar Program, AIL also developed a complement of radar-functional modules. Moving target indicator (MTI) light-weight modular surveillance radars (LMSRs) satisfy reconnaissance, surveillance and target acquisition (RSTA) needs while the addition of a single module can provide a Spotlight Synthetic Aperture Radar (SAR) imagery capability. Because of their modular design, these radars are configured for manned and unmanned airborne platforms, ground vehicles and man-portable missions. The radar system is platform independent, reducing acquisition, mainten-ance and training costs.
| AN/APS-144 in Amber fuselage |
Platforms equipped with LMSRs provide wide-area surveillance capability during the day and night and in adverse weather conditions to dif-ferentiate between moving personnel, trucks, tanks and helicopters. The performance limitations that smoke, haze and moisture impose on electro-optic and infrared systems are overcome by using radars. In conjunction with multiple sensor systems, LMSRs provide rapid wide-area target detections and locations that are used to cue narrow field-of-view EO/IR sensors or provide spot fixed target imagery to enhance target recognition.
| A tactical RSTA system |
LMSRs are pulse-Doppler radars that provide high-resolution ground mapping. They use the Doppler frequencies of the radar returns to discriminate moving targets from clutter. Target recognition is provided by using Doppler fre-quency signal-processing algorithms to distin-guish tracked from wheeled vehicles, personnel movement and hovering helicopters. Advanced signal processing will automate target recog-nition within tactically meaningful timelines to reduce sensor-to-shooter operations.
Manned and unmanned airborne and ground LMSRs are networked to provide a local-area tactical RSTA system. Airborne sensors are used for over-the-horizon target detections and ground-based sensors provide long- and short- range line-of-sight target detections. Target information from either sensor platform is transmitted using commercially available narrow-bandwidth data links and this results in an integrated battlefield information system. This capability is essential to see the battlefield clearly and facilitate battle management, target priori-tisation and timely data dissemination for brigade and battalion soldiers and small unit operations. Enhanced situational aware-ness is achieved by providing soldiers with target information to locate and identify threat targets, thereby reducing friendly force vulnerability. Target acquisition data is provided to battlefield functional areas including man-oeuvre, fire support, air defence and intelligence and electronic warfare to reduce sensor-to-shooter timelines.
Brigade/battalion RSTA battlefield information systems using LMSRs can be integrated with existing stand-off surveillance assets to provide the complete RSTA system. As an adjunct to stand-off platforms, target information that may be masked by terrain would be trans-mitted to a common ground station and over-laid on a grid map display to provide a com-plete battlefield picture.
Tactical warfighters that are operating in parallel in regional conflicts are provided with overall surveillance coverage of the target area and targeting information.
| AN/APS-144 airborne MTI radar |
Working in conjunction with Lincoln Laboratories and with sponsorship from the Defense Advance Research Projects Agency (DARPA), AIL Systems fabricated, tested, installed and supported flight tests of an airborne modular radar. The system was integrated into the fuse-lage of an AMBER UAV captured to the under-side of a Twin Otter Piloted aircraft. Successful tests demonstrated the ability of a small, light-weight airborne MTI radar for UAV payloads to detect moving targets on the ground.
Under contract from Harry Diamond Labs, AIL configured a heavy-duty ground surveillance radar designated AN/TPS-74 for the elevated target acquisition system (ETAS). Mounted on an M113 Armoured Personnel Carrier atop a 20-metre mast, the radar system incorporated a heavy-duty pedestal that allowed for around-the-mast radar operation while supporting an independently steerable 400lb E0 Sensor pack-age. Tests at Ft Bliss, Texas in 1988 demonstrated wide-area battlefield surveillance and electronic cueing of an optical sensor capability. The radar detected moving ground vehicles and hovering helicopters at ranges of 20km.
| Platforms equipped with LMSRs provide wide-area surveillance capability during the day and night and in adverse weather conditions to differentiate between moving personnel, trucks, tanks and helicopters |
In 1989, the US Army and AIL began a series of tests and demonstrations aimed at validating the capability of the airborne MTI radar, designated AN/APS-144 for drug interdiction and battlefield surveillance. Tests on the AN/APS-144 when mounted under a UH-60 Blackhawk helicopter were conducted by PM Grisley Hunter at Ft AP Hill and demonstrated the detection of moving personnel at ranges of 12km and moving vehicles at ranges of 20km. These tests concluded with the concept evaluation program (CEP) flown at the National Training Center Ft Irwin, CA as Operation Desert Capture I.
| LMSR core modules |
Flown in a UAV surrogate platform in a battle-field surveillance role, targets detected by the AN/APS-144 were data-linked in real time to the ground for display in the Joint Surveillance Target Attack Radar System (JSTARS) light-weight ground station module.
To meet an emerging demand for border surveillance and security, AIL designed a mobile multi-sensor surveillance system using the AN/TPS-74 ground-based radar in 1993. The radar system is mounted in a militarised shelter on a heavy HMMWV and provides a wide area (>30km range) surveillance capability that cues built-in daylight TV/FLIR EO sensors. Tests at Ft Hood, Texas demonstrated long-range target detection, classification and real-time data links. Targets detected included personnel, tracked/wheeled vehicles and moving helicopters. This system also has been successfully tested overseas.
AIL also has developed tactical spotlight imagery using synthetic aperture radar (SAR) to provide high-resolution imagery for specific target identification. This capability, designed as a module, will be incorporated into AIL's airborne MTI radar to provide a dual function lightweight MTI/SAR radar for manned and/or unmanned platforms.
The resulting concept of modular radar has evolved to become lightweight modular sur-veillance radars. Radar functional modules con-figured as airborne and/or ground radar systems weigh less than 75lbs. LMSRs detect, track and classify slow-moving targets in a back-ground of clutter, providing the sensor of choice for rapid wide-area surveillance and tracking with the added flexibility to cue multiple sensors.
