3D radar

3D radar provides for radar coverage on three dimensions unlike the more common 2D radar. While the normal 2D radar provides range and azimuth, the 3D radar provides elevation information with range and azimuth. Applications include weather forecasting, defense and surveillance.

3D Radar Techniques

Steered Beam radars steer a narrow beam through a scan pattern to build a 3-D picture. Examples include NEXRAD doppler weather radar (which uses a parabolic dish) and the SPY phased-array radar employed by the Aegis class of missile cruiser.
Stacked Beam radars emit and/or receive multiple beams of radio waves at two or more elevation angles. By comparing the relative strengths of the returns from each beam, the elevation of the target can be deduced. An example of a stacked beam radar is the ARSR-4.

Figure 1: Diagram of a typical 2D-Radar rotating cosecant squared antenna pattern

Figure 2: Diagram of a typical 3D-Radar, a judicial mix of vertical electronic beam steering and mechanically horizontal movement of a pencil-beam

External links

* [http://www.cea.com.au/products/phasedarray/ceafar.html CEA FAR 3D Radar]
* [http://www.rrs.co.za/products/3d-surveillance.htm ESR 360L 3D Surveillance Radar]