The measurement of water level based on parallel-coupled lines with capacitance compensation


  • Somchat Sonasang Department of Electronic Technology, Faculty of Industrial Technology, Nakhon Phanom University, Nakhon Phanom, 48000 Thailand
  • Ravee Phromloungsri Department of Computer and Communication, Engineering, Faculty of Technology, Udon Thani Rajabhat University, Udon Thani, 41000 Thailand



Water Level, Parallel-coupled Lines, Capacitance Compensation


This paper aimed to measure the water level using parallel-coupled microstrip lines with capacitor compensation. The design and implementation were parallel coupled microstrip lines with capacitor compensation to measure the water level. The technique of parallel-coupled microstrip lines had a coupling coefficient of – 10 dB. The center frequency was 200 MHz, and the compensated capacitor was positioned at ports 3 and 4. The water level was adjusted from 0 to 20 cm in the experiment. The frequency response of the coupling factor was measured from 300 kHz to 2 GHz. The coupling coefficient at 200 MHz was – 11.45 dB at 0 cm water level, where a shift of frequency decreased continuously. This technique was simple to follow, as the sensor was small and inexpensive.


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How to Cite

Sonasang, S., & Phromloungsri , R. . (2022). The measurement of water level based on parallel-coupled lines with capacitance compensation. Creative Science, 14(2), 245039.