Solid State Science and Technology, Vol. 15, No 1 (2007) 13-21

ISSN 0128-7389

Corresponding Author: kaida@fsas.upm.edu.my

13

ANALYSIS OF A CONDUTOR-BACKED COPLANAR WAVEGUIDE MOISTURE SENSOR

Kaida bin Khalid  and Teoh Lay Hua

Physics Department, Universiti Putra Malaysia

43400, UPM Serdang Selangor Malaysia.

 

ABSTRACT

The analysis of conductor-backed coplanar waveguide moisture sensor by using numerical  method is presented.  The structure of the sensor is based on the 4-layer system which consists of RT-duriod substrate, protective cover, moist layer and air. The numerical analysis involves with the calculation of effective dielectric constant, characteristic impedance and dielectric loss of the multi-layer structure at various moisture contents  with  respect  to  protective  layer  thickness.  A reasonable close agreement between computed and experimental data for attenuation of the sensor at various moisture contents ranging from 30% to 80% (wet basis) of the oil palm fruit has been achieved. This analysis is useful for the prediction of the dynamic range and sensitivity  of  the  sensor  by  choosing  suitable  thickness  of  the  protective  layer  ,geometrical parameters and substrate of the sensor.

 

http://journal.masshp.net/wp-content/uploads/Journal/2007/Jilid%201/Kaida%20bin%20Khalid%20%2013-21.pdf

 

REFERENCES

 

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[8]       Kaida  Khalid  and  Teoh  Lay  Hua,  (2004).  The  Analysis  of  Multi-layer Conductor-  backed  Coplanar  Waveguide  for  Moisture  Sensor  Application, Subsurface Sensing Techologies ans Applications, Vol 5,No.2 pp 63-78

[9]       Khalid, K.B., Zakaria, Z. and Daud, W.M., (1996), Variation  of  dielectric properties of oil palm mesocarp with moisture content and fruit  maturity at microwave frequencies, Elaeis Vol. 8, No. 2, p. 83-91.

 

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In : Microwave Aquametry , IEEE Press,  USA.  p. 239- 248