Guidance for Radar Level Measurement Applications » Guided Wave Radar Level Measurement
Low power, nano-second microwave pulses are guided down a
probe submerged in the process media. When a microwave pulse
reaches a media with a different dielectric constant, part of the
energy is reflected back to the transmitter.
The transmitter uses the residual wave of the first reflection for
measuring the interface level. Part of the wave, which was not
reflected at the upper product surface, continues until it is reflected at
the lower product surface. The speed of this wave depends fully on
the dielectric constant of the upper product.
The time difference between the transmitted and the reflected pulse
is converted into a distance, and the total level or interface level is
then calculated. The reflection intensity depends on the dielectric
constant of the product. The higher the dielectric constant value, the
stronger the reflection is.
See blog post at: www.emersonprocessxperts.com/archives/2011/04/guidance_fo…