Level-measuring device which functions with microwaves

Abstract

The invention relates to a level-measuring device which functions especially with microwave bursts and which is used to produce a measuring value (XH) representing the level inside a container (200). The level-measuring device comprises a transceiver (2) which is used to produce an intermediate frequency signal (ZF), which is influenced by the filling level, by means of a send signal (S2) and a receive signal (E2). The filling-level measuring device also comprises a converter element (1) which, when in operation, is controlled by the send signal (S2) and which injects especially pulsed transmission waves (S1) into the container, converting reflected echo waves (E1) from the filling material (201) into the receive signal (E2). The intermediate frequency signal (ZF) is fed to a control unit (3) of the filling-level measuring device and digitally stored in the form of a scanning sequence (AF) in a volatile data memory (33), whereby amplitude and phase information is also available upon determination of the filling level. The filling-level measuring device is thus able to measure the filling level in a very fast, highly accurate manner, down to the last millimetre.

Description

technical field [0001] The invention relates to a liquid level measuring device which utilizes microwaves to work. Background technique [0002] For measuring, in particular quasi-continuously measuring, the liquid level in containers, for example tanks or containers, liquid level measuring devices which operate with microwaves are often used. When using this liquid level measuring device based on the radar principle to measure the liquid level, electromagnetic waves are emitted to the material to be measured in the form of space waves through the antenna or guided waves through the surface waveguide, especially the center frequency Electromagnetic waves from about 0.5 to 30 GHz. Due to the discontinuities in the electrical impedance in the container containing the substance, the aforementioned waves are partly reflected, in particular by the surface of the substance, and returned to the level measuring device as echo signals via surface waveguides or antennas. [0003] In...

AI Technical Summary

Problems solved by technology

In addition, in order to ensure that the determined transit time is sufficiently accurate, each component used must be of the following typical type, that is, the component parameters change little, have high long-term stability, and must be connected with high precision. line, so the cost is very high

Images