Airborne radar (also known as Airborne Interception Radar, or AI) is also known. It is a type of radar that equips aircraft in the air-to-air role. It employs multiple sensors to track a target's position. A common use of airborne radar is to detect hostile missiles and aircraft.
Doppler effect
Airborne radar will detect a signal coming from a target and it will appear as if it is increasing in frequency. The effect is due to the Doppler effect. Doppler-frequency, which is a measure for radial speed, is commonly called "normalized". This property allows radars to process echo signals from different radar frequencies together.
When waves of different frequencies are directed by an object moving, the Doppler effect is observed. The wave from the point source is compressed in one direction, and expanded in the opposite direction. This effect is greater when the object is moving fast. The frequency of the sound at the right angles to the motion does not change.
Ground Range
Ground ranging via airborne radar means using a radar device to detect objects on a ground surface. This technique is common in military reconnaissance and terrain mapping. It is also used by NASA and airborne research systems. It can also be used on satellites such as the Russian ALMAZ satellite or the Japanese JERS-1.
Ground ranging on airborne radar uses high-frequency radio waves to detect objects on the ground. The frequency used for this is dependent on the application. Radars with higher frequencies are smaller.
Contouring
Use of airborne radar to forecast weather is a great way for storms to be detected before they reach the ground. Before you deploy this powerful tool, however, there are a few things that you need to know. These factors include your personal judgment, the season, and where you live. Avoid flying in the direction of steep terrain, for instance.
Contour interpolation is the basic method of contouring an area. This method exploits natural terrain's redundancy and offers a simplified way to reconstruct the height of terrain. It works much the same way as conventional topographic maps. Context interpolation can be used to determine the height for any point on a radar sweep. This is done by interpolating the height of the contour immediately surrounding the point with the height of all other contours. A continuum of points can be created by interpolating these contours' heights.
Attenuation
Attenuation of airborne radar occurs on both the outward and return paths of radar signals. C band radar would encounter a 60 dBZ reflective core and lose 10dBZ in signal strength along the outward pathway. The return path would suffer a 20dBZ loss. This would lead to reflectivity returns for precipitation that is farther from radar being 20dBZ lower then actual. However, the S band radar would encounter the same core and experience only 2dBZ intenuation.
Attenuation is an important part of radar technology. It is useful for meteorologists in identifying thunderstorms which may be hundreds of kilometers away. It also creates radar scope shadows which alert airborne planes to potentially dangerous weather conditions, terrain, and cities beneath their flight paths.
Reflection
Reflection occurs when electromagnetic pulses from a radar bounce off a target's surface. This is called specular reflection. The frequency of the echoes depends upon the antenna pattern, and the length the transmitted pulse. The phase of the echos along the track can also vary. The phase of the echoes at nadir points is zero. The farther the radar is from the target, the more the phase changes.
Reflection on airborne radar is also influenced by airborne weather conditions. When temperatures are warmer, radar reflectivity tends toward the surface. High reflectivity conditions however tend to decrease toward surfaces.