What does a radar antenna look like?

The radar antenna is like a bat's (mouth) radar image refers to a continuous strip scan image obtained by an active imaging radar system. Such as side-looking radar images. It uses a radar antenna to emit microwave beams to scan the ground, then receives the reflected echo signals, and records and images them on film after information processing. Real aperture radar images have low azimuth resolution due to the size limitation of the radar antenna. Synthetic aperture radar images use synthetic aperture and coherent signal processing technology to greatly improve the azimuth resolution of the image. Radar images have a shadow effect similar to that produced by photography at low solar angles, and have good image characteristics for micro-terrain undulations. However, for large negative terrain areas, radar blind spots occur, resulting in missing images of ground objects in the blind spots. Its geometric relationship is different from conventional aerial photos or passive scanning images. For example, side-looking radar images are of the slant-range projection type, that is, all ground object points located on the same wavefront sphere emitted by the antenna are imaged at the same point. The image point displacement (distortion) caused by the height difference of ground objects is also in the opposite direction to the center projection aerial photo. The farther the ground objects are from the antenna, the less affected they are by terrain fluctuations. Therefore, when using radar images for stereoscopic observation, the positions of the left and right images should be swapped to avoid looking inversely stereoscopically. The color tone of side-looking radar images depends on the backscattering intensity of microwaves by ground objects, and is comprehensively affected by factors such as surface roughness of ground objects, soil conductive properties, microwave wavelength, polarization type, and echo incident angle. Therefore, the concept of conventional aerial photo interpretation signs cannot be copied to understand the information characteristics of radar images.

So the radar antenna is like a bat’s (mouth)