Surface Radars Ground Based Defence Radars - Naval Defence Radars

The purpose of land and naval defence radars is to detect all objects and/or, as the case may be, all persons likely to constitute a threat: aircraft of all kinds (planes, helicopters, missiles, drones, shells...), ground vehicles (tanks, troop convoys, vehicles of all kinds...), ships (from the largest such as aircraft carriers to the smallest such as dinghies), infantrymen, combat swimmers...

Not only are the targets non-cooperative, but they also tend to be difficult to detect: reduced reflection of radar waves, low-altitude trajectories, masking behind terrain relief. Moreover, the context in which defense radars are used is a hostile one. Enemies can use electronic countermeasures to alter radar operation. They can also fire anti-radiation missiles aimed at radar emissions. Defense radars therefore have the means to protect against these threats, and automatic procedures to guard against them.

Since the objects to be detected are non-cooperative, primary radars are used for detection. They are usually combined with secondary radars that provide "friend or foe" information (IFF, Identification Friend or Foe).

Beyond the association of a primary radar and a secondary radar, defense radars are above all components of a defense system, which combines detection and localization means (of which radars are a part), communication, information fusion and processing, in land command and control centers or in naval combat systems, and finally response means, to counter attacks.

Defense radars are therefore designed to be integrated into a defense system, contributing to the system's mission by detecting, locating and recognizing targets.

• They are dimensioned according to the protection domain provided by the defense system: range, information renewal rate, non-cooperative target recognition capabilities. Their architecture is defined with a view to the capabilities required by the defense system: surveillance, tracking or multi-function radars. Their functionalities are developed according to the needs of the system: for example, a counter-battery radar's ability to accurately measure shell trajectories, a kill assessment for a land-based fire control system, or splash spotting to guide the firing of a naval system.

• They respect the mechanical constraints of the defense system. Whether it's a land-based weapon system or a naval combat system, the latter imposes size limits on the external part of the radar (the antenna) and also on all the internal parts. It also imposes constraints in terms of total mass and weight distribution between the upper and lower parts. In some naval combat systems, this is the system that imposes a fixed-panel architecture on the radar, arranged...