**3. Further research**

Other boards fabricated using different agricultural waste materials should also be investigated. This will also depend on the waste material's availability, based on the geographical region and type of agricultural/economic activities. On the other hand, the current scope can be expanded to evaluate boards with different thicknesses, as MUT's thickness could affect measurement accuracy. It is also evident that improvement on the measurement setup is relevant, especially on the free space measurement technique.

Alternatives for PCB Laminates: Dielectric Properties' Measurements at Microwave Frequencies 111

[4] Nakhkash, M., Yi Huang, Al-Nuaimy, W., & Fang, M.T.C., (2001) An Improved Calibration Technique for Free Space Measurement of Complex Permitivity, IEEE

[6] Suhardy Daud, Mohd Nazry Salleh, Farizul Hafiz Kasim and Saiful Azhar Saad (2005) Analysis of Chemical Elements in Major Perlis's Agricultural Residue School of Materials Engineering, Kolej Universiti Kejuruteraan Utara Malaysia (KUKUM).

[7] Gagnon, N., Shaker, J., Roy, L., Petosa, A., & Berini, P., (2004) Low Cost Free Measurement of Dielectric Constant at Ka Band, IEEE Proceedings - Microwaves,

[8] Ghodgaonkar, D.K., Varadan, V.V., & Varadan, V.K., (2009) A Free Space Method for Measurement of Dielectric Constants and Loss Tangents at Microwave Frequencies, IEEE Transactions on Instrumentation and Measurement, Volume: 38, Issue: 3, pp 789-

[9] Maryam, M.I., Ibrahim, N., Shamsudin, R., & Marhaban, M.H., (2009) Sugar Content in Watermelon Juice Based on Dielectric Properties at 10.45GHz, 2009 IEEE Student

[10] Ministry of Agriculture, (1995) Malaysian Agricultural Directory & Index 1995/96 (sixth

[11] Navarkhele, V. V., Nakade, S.T. & Shaikh, A.A., (2006) A Dielectric Approach to Determine Water Content in Soil Using Microwave Transmission Technique. Journal of

[12] Nelson, S.O., (2003) Measuring Dielectric Properties of Fresh Fruits and Vegetables, 2003 IEEE Antennas and Propagation Society International Symposium, Vol. 4, pg 46-

[13] Nelson, S.O., Wen-chuan Guo, Trabelsi, S., & Kays, S.J., (2007) Sensing Quality of Watermelons Trough Dielectric Permittivity, 2007 IEEE Antennas and Propagation

[14] Popovic, D., Okoniewski, M., Hagl, D., Booske, J.H., & Hagness, S.C., (2001) Volume Sensing Properties of Open-ended Coaxial Probes for Dielectric Spectroscopy of Breast Tissue, Antennas and Propagation Society International Symposium, Vol 1, pp

[15] Padiberas Nasional Berhad, (2007) Padiberas Nasional Berhad - Annual Report 2007,

[18] Shu Chen, Kupershmidt, J., Korolev, K.A., & Afsar, M.N., (2007) A High Resolution Quasi Optical Spectrometer for Complex Permittivity and Loss Tangent Measurements

[16] Pozar, M.D., (2005) Microwave Ebgineering, Third Edition, John Wiley & Sons Inc. [17] Sheen, J. (2007) Microwave Dielectric Properties Measurements Using the Waveguide Reflection Dielectric Resonator, IEEE Instrumentation and Measurement Technology

Transactions on Geoscience and Remote Sensing, Volume 39, Issue 2, pg 453-455. [5] J. Obrzut, A. Anopchenko and R. Nozaki (2005) Agricultural Fibers For Use in Building

Component. Technology Conference Ottawa, Canada, 17-19 May*.* 

Antennas and Propagation, Volume 151, Issue: 3, pg 271-276.

Conference on Research and Development (SCOReD), pg 529-532.

Measurement Science Review, Volume 5, Section 3.

edition), Kuala Lumpur, Malaysia, pg. 107.

the Indian Institution of Science, 86, 723–729.

Society International Symposium, pg 285-288.

Conference Proceedings, 2007 (IMTC 2007), pg 1-4.

793.

49.

254-257.

Petaling Jaya, Selangor.
