The difference between ultrasonic level meter and microwave level meter

What is the difference between ultrasonic level meter and microwave level meter?

We often hear ultrasonic level meters and microwave level meters, but we are not sure where the difference is between the two. Today we have a simple understanding of the introduction of Instrument World.

There are two main installation methods for ultrasonic level meters. One is the top installation, and the other is the bottom installation. The ultrasonic level meter uses the liquid sound conduction. The ultrasonic probe is installed outside the bottom of the tank and the ultrasonic wave is transmitted from the bottom. The liquid is transmitted to the liquid surface and reflected back to the probe. The propagation time is directly proportional to the level of liquid.

The microwave level meter propagates at the speed of light, and the speed is almost unaffected by the characteristics of the medium. The propagation attenuation is also small, about 0.2 dB/km. The strength of the echo signal strongly depends on the reflection on the liquid surface being measured. The reflectivity on the measured liquid surface depends on the relative permittivity εr of the material, in addition to the area and shape of the measured material. The relative permittivity is high, the reflectance is also high, and the obtained echo intensity is high. When the relative permittivity is low, the material absorbs part of the microwave energy and the echo intensity is low.