Showing posts with label Open Air Level Measurement. Show all posts
Showing posts with label Open Air Level Measurement. Show all posts

Monday, January 20, 2020

FMCW (Frequency Modulated Continuous Wave) Open Air Radar Level Measurement

Non-contact level measurement using radar transmitters for the continuous, contactless level measurement of liquids, pastes, granulates, powders and other solids in a wide variety of industries.


Frequency Modulated Continuous Wave

OPERATING PRINCIPLE
  • The radar principle used is FMCW (Frequency Modulated Continuous Wave). The FMCW radar emits a high frequency signal whose frequency increases linearly during the measurement phase (called the frequency sweep). 
  • The signal is emitted via an antenna, reflected off the product surface and received with a time delay, t. 
  • Time delay, t=2d/c, where d is the distance to the product surface and c is the speed of light in the gas above the product. 
  • For further signal processing the difference Δf is calculated from the actual transmitted frequency and the received frequency. 
  • The difference is directly proportional to the distance.
  • A large frequency difference corresponds to a large distance and vice versa. 
  • The frequency difference f is transformed via a Fast Fourier Transformation (FFT) into a frequency spectrum and then the distance is calculated from the spectrum.
  • The level results from the difference between the tank height and the measured distance.

For additional information, call Piping Specialties, PSI Controls at 800-223-1468 or visit their web site at https://psi-team.com.