For countless soldiers deployed over the past decade who have heard a siren warning of an incoming attack, C-RAM (counter rocket, artillery and mortar) systems have provided precious seconds needed to take cover.

C-RAM is made up of a variety of systems that not only sense and warn of inbound attacks from the skies but can destroy incoming rockets, artillery and mortar rounds in the air before they hit the ground, according to NATO.

The systems are used by militaries around the world to defend troops, key assets, infrastructure and populated civilian areas.

Iron Dome shows high success rate

The best-known C-RAM system is Israel's Iron Dome, which is used to protect Israeli citizens and infrastructure, and had a 96% success rate in intercepting rockets fired from Gaza during the most recent conflicts between Israeli and Palestinian factions, Reuters reports.

Iron Dome, developed by US defense contractor RTX (formerly Raytheon) and Israeli defense company Rafael Advanced Defense Systems, assesses and intercepts a variety of short-range threats such as rockets, artillery and mortar rounds, according to RTX.

The system is functional day or night and in all weather conditions, RTX says, including low clouds, rain, dust storms and fog.

It is designed to fire a variety of interceptor missiles, and its Tamir missile can knock down incoming threats launched from 4 to 70km away.

The system is capable of handling multiple threats simultaneously, according to Rafael.

C-RAM's 'sense and warn' capabilities

The US Army's version of the C-RAM system was first developed early during Operation Iraqi Freedom/Enduring Freedom in the early 2000s, according to the Missile Defense Advocacy Alliance (MDAA).

It was developed in response to a significant number of troop deaths in Iraq caused by rocket, artillery and mortar attacks, reports GlobalSecurity.org.

The US C-RAM system's components include the Forward Area Air Defense Command and Control (FAAD C2) software, which "senses and confirms the threat, provides early warning to the specific impact area at risk, tracks the threat trajectory, and engages the in-bound threats," manufacturer Northrop Grumman says.

The C-RAM system also includes Land-based Phalanx Weapons Systems, a rapid-fire, computer controlled radar and 20mm gun system that acquires, tracks and destroys enemy threats.

It includes Lightweight Counter Mortar Radars and firefinder radars, mobile radar systems used to locate rocket, artillery and mortar attack points of origin.

In addition, the C-RAM incorporates the Ku Band Multi-Function Radio Frequency System, a 360-degree radar that senses incoming drones, rockets, and artillery and mortar rounds, and the Air and Missile Defense Workstation, a battlespace situational awareness tool, among other components that contribute to system intercept and communications, MDAA reports.

In Iraq and Afghanistan, where C-RAM was operationally deployed, the system's "sense and warn" capabilities flagged more than 2,500 rocket and mortar attacks against C-RAM-equipped forward operating bases, MDAA reports.

The system has also been purchased by Australia and the United Kingdom.

Other variants

The Netherlands utilizes Goalkeeper, a close-in weapon system that provides short-range defense of ships against highly maneuverable missiles, aircraft and surface vessels, reports Sea Forces online.

The system is autonomous and once activated is capable of automatically surveilling, detecting and destroying threats and of selecting the next priority target.

Introduced in 1979, the Goalkeeper uses the GAU-8/A Avenger 30mm, seven barrel Gatling gun.

Another variant of C-RAM is Germany's Nächstbereichschutzsystem (NBS) MANTIS, a very short-range air defense protection system developed for protecting German army bases in Afghanistan, according to Army Technology.

The anti-aircraft artillery complex, which is not mobile, consists of six 35mm guns based in ground towers, two sensor devices and a control system, reports Mezha.

The system is fully automated, allowing guns to fire instantly as radar sensors track incoming threats. The guns are capable of firing 1,000 rounds per minute, Army Technology reports.

The first fully functional NBS unit was obtained by the German Luftwaffe in 2010 and deployed in 2011.

Another C-RAM system designed for the Italian army -- the Porcupine -- never made it out of the prototype phase, according to Mezha.

Italian defense company OTO Melara announced in 2014 the system would include a remotely controlled M61A1 Gatling gun, along with an ammunition handling loader and a stabilized optronic infrared tracking system to provide 24-hour target engagement capability, reports Army Recognition.

A typical Porcupine configuration would include four firing units, a central control post and a 3D radar system for surveillance and target tracking.

OTO Melara also developed the DRACO, a multi-purpose weapon station intended to operate against air, rocket, artillery, mortar and surface targets. The defense system also did not advance past the prototype phase, Mezha reports.

DRACO's main component is a 76/62mm gun with an automatic ammunition loading system, according to OTO Melara, and can be installed on 8x8 wheeled platforms for combat support operations or convoy defense.

It can also be installed on tracked vehicles or shelters for point defense, according to OTO Melara.

Taken together, these C-RAM systems are effective short-range air defense tools that protect lives, infrastructure and assets. The systems are also evolving to respond to new threats, according to Northrop Grumman, such as those from unmanned aerial vehicles, commonly known as drones.