Counter-battery radar

A counter-battery radar (alternatively Weapon Tracking Radar or Target Acquisition Radar) is a mobile radar system that detects artillery projectiles fired by one or more guns, howitzers, mortars or rocket launchers and, from their trajectories, locates the position on the ground of the weapon that fired it. More advanced systems can electronically send aiming instructions to friendly artillery for firing at hostile targets with counter-battery fire. Some radars like the AN/TPQ-37 or the COBRA can calculate where hostile projectiles will land. Modern counter-battery radar can locate hostile batteries up to about 50 km away depending on the radar's capabilities and the terrain and weather. A counter-battery radar is attached to an artillery battery or their support group.

If the radar is fast and has good communications, then it may be possible to provide some warning to troops targeted by the incoming projectiles. However, many projectiles have a time of flight under a minute, which makes it difficult to give warnings without a highly automated communication system, unless the target is in the vicinity of the radar. Some counter-battery radars can also be used to track the fire of friendly artillery and calculate corrections to adjust its fire onto a particular place, but this is usually a secondary mission objective.

Radar is the most recently developed means of locating hostile artillery. The emergence of indirect fire in World War I saw the development of sound ranging, flash spotting and air reconnaissance, both visual and photographic. Radars, like sound ranging and flash spotting, require hostile guns, etc., to fire before they can be located.

The first radars were developed for anti-aircraft purposes just before World War II. These were soon followed by fire control radars for ships and coastal artillery batteries. The latter could observe the splashes of water from missing shots, enabling corrections to be plotted. Generally the shells could not be seen directly, as they were too small and rounded to make a strong return, and traveled too quickly for the mechanical antennas of the era to follow.

Radar operators in light anti-aircraft batteries close to the front line found they were able to track mortar bombs. This was likely helped by the fins of the bomb producing a partial corner cube that strongly reflected the signal. These accidental intercepts led to their dedicated use in this role, with special secondary instruments if necessary, and development of radars designed for mortar locating. Dedicated mortar-locating radars were common starting in the 1960s and were used until around 2000.

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