Radar has the ability to “see through” certain materials and atmospheric conditions, depending on the frequency and design of the radar system. Typically, radar waves can penetrate through materials such as clouds, fog, rain and snow, allowing radar systems to detect objects beyond these obstructions. This capability is particularly useful in weather radar applications where precipitation can obscure visibility, but still allows radar signals to reflect targets such as aircraft, ships or the terrain below. However, radar waves can experience attenuation or weakening when passing dense materials such as metal or buildings, limiting their ability to penetrate and detect objects behind solid barriers.
Radar can detect a wide range of objects based on their size, shape, material composition and radar cross section (RCS). Common targets detected by radar include aircraft, ships, vehicles, weather phenomena (like rain and storms), terrain features, and even satellites. Radar systems emit electromagnetic waves that bounce off these objects and echo back to the radar receiver. By analyzing the timing and characteristics of these echoes, radar systems can determine the presence, location, speed and other parameters of detected objects. This capability makes the radar valuable in military surveillance, air traffic control, weather monitoring, and various scientific and commercial applications.
There are limits to what radar can detect, mainly related to the properties of the object and the design of the radar system. Radar waves have difficulty detecting objects with very low RCs, such as small birds, insects, or stealth aircraft designed to minimize radar reflections. Objects that absorb radar waves, such as certain materials or objects with specialized coatings, can also be difficult for radar systems to detect. Additionally, radar performance may be affected by environmental factors such as heavy precipitation, dense foliage, or electromagnetic interference, which can obscure or distort radar signals and reduce detection capabilities under these conditions.