System and method in a radar level gauging system

摘要

The present invention relates to the field of radar level gauging systems, in which a level of a surface of a product stored in a container is measured. The gauging system comprises: a radar level gauge arranged above the surface of the product which is arranged to transmit a microwave signal towards the product surface and receive a reflected microwave signal from the product surface; a calculation unit arranged to determine a measured value of the product level based upon the received signal; means for comparing the measured value of the product level with a predetermined value; and a second level gauge arranged closed to the bottom of the container and arranged to determine the product level when the measured value is below the predetermined value.