Air-Search Radar

Air-Search Radar The primary function of an air-search radar is to maintain a 3600 surveillance from the surface to high altitudes and to detect and determine ranges and bearings of aircraft targets over relatively large areas. r a d a r: The following are some applications of an air- search radar: Gives early warning of approaching enemy aircraft and missiles, providing the direction from which an attack could come to allow time to bring antiaircraft defenses to the proper degree of readiness and to launch fighters if an air attack is imminent. Observes constantly the movement of enemy aircraft, once detected, to guide combat air patrol (CAP) aircraft to a position suitable for an intercept. Provides security against attacks at night and during times of poor visibility. Provides information used for aircraft control during operations that require a specific geo- graphic track (such as an antisubmarine bar- rier or a search and rescue pattern). Together, surface- and air-search radars provide a good early-warning system. However, the ship must be able to determine altitude to effectively intercept any air target. This requires still another type of radar. 3-D Radar The primary function of a 3-D radar is to compute accurate ranges, bearings, and altitudes of targets detected by an air-search radar. This information is used to direct fighter aircraft during interception of air targets. The 3-D radar is different from the air-search radar in that it has a higher transmitting frequency, higher output power, and a much narrower vertical beamwidth. In addition, it requires a stabilized an- tenna for altitude accuracy. The following are some applications of a 3-D Obtains range, bearing, and altitude data on enemy aircraft and missiles to assist in the guidance of CAP aircraft. Provides precise range, bearing, and height in- formation for fast and accurate initial position- ing of fire-control tracking radars. Detects low-flying aircraft. Determines range to distant landmasses. Tracks aircraft over land. Detects certain weather phenomena. Tracks weather balloons. The modern warship has several radars. Each radar is designed to fulfill a particular need, but may also be capable of performing other functions. For example, most 3-D radars can be used as secondary air-search radars; in emergencies, fire-control radars have served as surface-search radars. A 3-D air-search radar is shown in figure 1-5. Figure 1-5.—3-D air-search radar. 1-9