What types of weather radar can be divided into?

Any radar without Doppler performance is called incoherent radar or conventional weather radar, and a radar with Doppler performance is called coherent radar or Doppler radar. The main weather radars are:

Cloud measuring radar

It is a radar used to detect the height, thickness and physical characteristics of clouds that have not formed precipitation. Its commonly used wavelengths are 1.25 cm or 0.86 cm. The working principle is the same as that of rain measuring radar, and it is mainly used to detect the height of cloud tops and cloud bottoms. If there are multiple layers of clouds in the sky, the height of each layer can also be measured. Since cloud particles are smaller than precipitation particles, the working wavelength of cloud measuring radar is shorter. Cloud measuring radar can only detect high-level clouds and mid-level clouds with relatively few clouds. For low-level clouds with large water content, such as cumulonimbus clouds and hail, the cloud radar beam is difficult to penetrate, so it can only be detected by rain radar.

Rain detection radar

Also known as weather radar, it uses the scattering effect of raindrops, cloud droplets, ice crystals, snowflakes, etc. on electromagnetic waves to detect precipitation in the atmosphere or large droplets in clouds. concentration, distribution, movement and evolution to understand the structure and characteristics of weather systems. Rain measuring radar can detect typhoons, severe storms in local areas, hail, heavy rain and strong convective clouds, etc., and can monitor weather changes.

Wind measuring radar

It is used to detect horizontal wind direction, wind speed, air pressure, temperature, humidity and other meteorological elements in different atmospheric layers at high altitudes. The detection method of wind radar generally uses tracking reflection targets or transponders hung on balloons to continuously locate the balloons. Based on the displacement of the balloon per unit time, the horizontal wind direction and speed of different atmospheric layers can be determined. A radiosonde is also hung on the balloon to remotely measure the air pressure, temperature and humidity at high altitudes.

Circular polarization radar

General weather radars emit horizontally polarized waves or vertically polarized waves, while circularly polarized radars emit circularly polarized waves. When radar emits circularly polarized waves, the echo of spherical raindrops will be circularly polarized waves rotating in the opposite direction. Non-spherical large particles (such as hail) will cause depolarization of circularly polarized waves. Non-spherical hail can be used to detect circularly polarized waves. With the depolarization echo characteristics, circular polarization radar can be used to identify the presence of hail in the storm.

Frequency modulated continuous wave radar

It is a radar that detects the boundary layer atmosphere. It has extremely high distance resolution and sensitivity and is mainly used to measure the fluctuations, wind and turbulence of the clear-sky atmosphere in the boundary layer (see Atmospheric Boundary Layer).