GROUND BASED RADARS – ULTIMATE INTRUSION SENSORS

IAI Elta EL/M-2127 ground surveillance radar. Photo: IAI
IAI Elta EL/M-2127 ground surveillance radar. Photo: IAI

Ground based radar systems have gained operational importance in advanced systems aimed at detecting hostile persons in border zones and near critical installations.

The need to detect and identify targets under any condition have spurred a vast effort to develop more advanced, more easy to operate ground based radar systems.

Homeland security is using advanced radars as a sensor that can detect a threat before it poses a real danger.

Elta, the fully owned subsidiary of Israel Aerospace Industries (IAI) is Israel’s radar house. Using its vast experience the company has developed some of the more advanced radar systems like the “Green Pine” phased array radar that is part of the Israeli Arrow system that is used to protect Israel from ballistic missiles and the systems that are used on airborne early warning (AEW) aircraft.

But the operations on the ground need advanced radars and Elta has been developing and manufacturing them for many years. In general the ground radars made by Elta can be put into four main categories according to the time of development or ‘generation’.

The US Customs and Border Patrol is operating Elta Systems EL/M-2112 Ground Master radar as part of the Mobile Surveillance System. Elta is providing the radars as a subcontractor to Flir Systems.
The US Customs and Border Patrol is operating Elta Systems EL/M-2112 Ground Master radar as part of the Mobile Surveillance System. Elta is providing the radars as a subcontractor to Flir Systems.

Ground Surveillance Radar Evolution

The first generation were Rotating Analog Radars. The second generation were Rotating Radars with Analog Transmitter and Digital Processing in Receiver. The third generation are non rotating radars covering a sector by electronic beam scanning. Some of the third generation radars are rotating, but significantly more capable then their predecessors, and and therefore considered to be third and a half Generation. The fourth Generation include persistent sSurveillance radars, consisting of static antenna covering a wide sector instantaneously by multiple electronically-steered beams.

Elta radars detect targets based on the target’s doppler effect and classify targets by doppler shift frequency analysis.  This family of ground radars uses a ‘Track Before Detect’ algorithm to reject moving vegetation as legal targets (since the vegetation does not change its distance). Starting from second generation, digital background maps can be implemented, which allows designating areas of interest or areas of non interest to save resources. Alarm zones within areas of interest can also be designated. Elta’s ground radars also have a ‘rain algorithm’ to enable target detection even in rainy conditions, enabling these ground surveillance radars to operate under adverse weather conditions. The company usually recommends adding day/night electro-optical systems to enable target Identification.

A good example for Elta’s second generation ground radars is the EL/M-2129 a coherent pulse compression ground based radar for military and paramilitary applications. This radar detects and monitors movements inside areas of interest.

The EL/M-2129 automatically detects moving targets such as walking person, vehicles and flying objects (gliders and helicopters), at ranges of up to 30 km. Longer ranges are available by adding a power amplifier or by increasing the antenna size. According to Elta this system can also be used for artillery fire correction, by spotting shell impact location.

A good example for Elta’s third generation ground radars is the EL/M-2127 smart miniature detection radar (SMDR). It detects and monitors intruder’s movements in selected zones of interest. The full solid state static radar operates automatically with an electronic beam steering within the covered pre selected sector. According to Elta this radar has been selected by customers either in a standalone configuration or as part of an integrated network defending a larger area.

The Elta EL/M-2112 Ground Master is part of a new family of ground radars that belongs to the fourth generation. This radar features up to 4 stationary (none rotating) planar antennas, each covering a sector of 90 degrees.

This radar has a detection range from 300 meters up to 20 kilometers for moving persons and ranges of up to 40 km for vehicles.

The EL/M-2112 and other radars of this family are designed for dual use – ground and sea surface surveillance, under all weather conditions including high sea. Another feature – this radar and other members of this family are capable to automatically adapt their processing (ground or sea) according to the relevant background map.

The Elta ground radars that in the past served mostly armies for defending borders or outposts, has gained popularity among operators of homeland security systems. “The Ground Surveillance Radar Market has shifted from strictly military operations to border and site protection applications in the homeland security (HLS) area” a company source told I-HLS.