Our radar level gauges use FMCW (Frequency Modulated Continuous Wave) technology.  The radar instrument is placed inside a vessel at the apex.  A microwave beam is continuously emitted with a modulating or changing frequency.  The frequency range usually occurs between 9 Ghz and 11 Ghz.  When the beam hits a liquid material it then bounces back to the instrument.  The differential in frequency is directly proportional to the distance traveled.  This information is converted into a level of the liquid in the tank. 

Advantages of Radar:

• Greater accuracy    
• Electromagnetic waves aren't affected by temperature or atmosphere    
• Tolerates higher pressure    
• Non-intrusive sensor with isolation seal for sanitized and corrosive environments