Radar Type Level Transmitter

The wavelength of 10 GHz is a little over an inch, whereas 75 GHz is a little over 1/8 of an inch. The latter would have a higher resolution as well as smaller components. The beam size is a function of wavelength to antenna size ratio.

Thanks Rixter for your response,

Actually i am much more concern about the process condition rather than antenna size or installation facilities.As i can fabricate those accordingly.Some articles and and supplier suggesting using frequency range in between 10 to 25GHz,for the above described process.Lower and mid range frequency does not absorbed much in the liquid due to higher wavelength.And it also disperse lesser by the ripple of turbulence.But some of the vendor using high frequency.Now can you please let me know what is typical operating frequency for such kind process as i am new in this field.I will also talk about this later with the supplier.

Thank you again

As an extension of going low for the frequency, I have the current history of some ultrasonic instruments installed and operating continuously since 1996 installed in tanks, some with 2-3 inches of foam, 150F liquid, vented, large water drops on the 3" diameter face, not a problem. The 2" pipes crossing within the 12 degree cone did cause trouble. Newer versions of this Canadian built instrument are even more versatile. The accuracy may not be as high as the higher frequency instruments, but lots more forgiving of process environment & general cleanliness, inside & out.

Much more reliable is head pressure sensing, 3" to 4" flush diaphragm, if you have a port low on the tank. Surface vapor, dirt, foam, ignored. The tank bottom has to be badly fouled to affect the reading, temperature corrected if necessary, just like ultrasonic/radar generally requires.

thank you, this article was helpful.