Radar MASINT
It involves the active or passive collection of energy reflected from a target or object by LOS, bistatic, or over-the-horizon radar systems.
It can be difficult to generate high power at the higher frequencies, or problems such as attenuation by water in the atmosphere limit performance.
Physically heavier than the LCMR, the AN/TPQ-36 Firefinder radar can detect cannon, rockets, and mortars within its range: It has a moving rather than omnidirectional antenna.
Current improvements are intended to replace its old control computer with a laptop, enhance performance in high clutter environments, and increase the probability of detecting certain rockets.
[8] The APS/PPS-15 is a lighter, shorter ranged version intended for airborne, light infantry, and special operations force use.
The COBRA DANE ground station radar is an "AN/FPS-108, a phased array L-Band antenna containing 15,360 radiating elements occupying 95% of the roughly 100 by 100-foot (30 m) area of one face of the building housing the system.
[12][13] The Soviet Union used a number of radar-equipped ocean reconnaissance satellites (RORSAT), which used strong radar systems, powered by an onboard nuclear reactor, to visualize vessels.
A synthetic aperture radar (SAR) system, exploits the fast movement of an aircraft or satellite, simulating a large antenna by combining samples over time.
[5] Coupled with other MASINT and IMINT sensors, SAR can provide a high-resolution day and night collection capability.
When operated at appropriate frequencies, it has ground- and water-penetrating capability, and is good for picking objects out of deliberate or natural clutter.
Flying on the MQ-1 Predator, the Northrop Grumman AN/ZPQ-1 Tactical Endurance Synthetic Aperture Radar (Tesar) started operations, in March 1996, over Bosnia.
A much more modest ISAR capability is on the Navy's[15] SH-60 multimission helicopter, carried on destroyers, cruisers, and aircraft carriers.
The German Armed Forces' (Bundeswehr) military SAR-Lupe reconnaissance satellite system has been fully operational since 22 July 2008.
Elevation-mapping interferometric SAR systems have since become an important remote sensing technology, with a very specific height-mapping mission.
Detection of mines, both on the active battlefield and in reconstituting nations with unexploded ordnance (UXO) remains a critical problem.
These radar systems were fully polarimetric and were generally designed to be mounted on an all-terrain vehicle for mobile applications on the battlefield.
[17][18] The railSAR was among the earliest of the UWB SAR technology at ARL and was constructed as a stationary, rail-guided impulse radar system.
The simplest form of this technology, known as coherent change detection (CCD), had obvious military and intelligence applications, and is now a valuable tool for analysts.
CCD complements other sensors: knowing that the surface changed may mean that analysts can direct ground-penetrating radar on it, measure thermal signatures to see if something is generating heat under the ground, etc.
That which makes them peculiarly MASINT, however is, especially in combination with other sensors and reference material, allows the measurement of a movement signature.
Current research and development involves multiple coherent SAR collections to make even more sensitive measurements, with the capability to detect motion as small as 1 mm per year.
[22] UHF and VHF SAR have begun limited operations on Army RC-12 aircraft and may be implemented on the Global Hawk.
[24] Technical approaches to fratricide prevention include: Radar offers the potential of non-cooperative target recognition (NCTR).
No one has yet proposed, however, NCTR that will be effective if a coalition partner is flying the same aircraft type as the enemy, as in Desert Storm.
[25] A 1997 Defense Department report mentions "Air Force and Navy combat identification efforts focus on non-cooperative target recognition technologies, including inverse synthetic aperture radar imaging, jet engine modulation (JEM), and unintentional modulation on pulse-based specific emitters".
[26] NCTR on JEM specifically depends on the periodic rotation of the blades of a turbine, with variations caused by the geometry of the elements of the engine (e.g., multiple rotors, the cowling, exhaust, and stators).
One of the first principles of stealth technology was to shape the surface of aircraft so that they did not reflect the transmitted beam directly back at the shared antenna.
Human activities generate a great deal of radio energy, as in communications, navigation, and entertainment applications.
Using the air traffic control illuminator, the receiver used pulse compression filtering of a chirp signal, which provided processing gain along with the ability to separate closely spaced targets.
This also implemented a moving target indicator that suppressed clutter, but it was recognized that an MTI signal would not be available in a noncooperative environment.
