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

ISSN 0128-7389

Corresponding Author:



Kaida bin Khalid  and Teoh Lay Hua

Physics Department, Universiti Putra Malaysia

43400, UPM Serdang Selangor Malaysia.



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.




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