METAL İPLİKLİ DOKUMA KUMAŞLARININ ELEKTROMANYETİK KALKANLAMA ETKİNLİĞİNİN MOBİL CİHAZLAR İLE TESPİTİ

Öz

Bu çalışmada metal iplik içerikli dokuma kumaşların elektromanyetik kalkanlama etkinliğinin (EMSE) yeni bir yöntem ile tespiti hedeflenmiştir. Bu amaçla metal tel içerikli ipek viskon karışımı iplikler üretilmiş ve bu iplikler atkı ipliği olarak, polyester iplikler de çözgü ipliği kullanılarak kumaş numuneleri elde edilmiştir. Üretilen kumaşlar öncelikle kafes oluşturabilmek için 2 eş parça kesilip 90 derece döndürülerek birbiri üzerine lamine edilmiştir. Laminasyon için belirlenen kat sayıları 2,4,8,12,16 olup bu kumaşların elektromanyetik kalkanlama etkinlikleri mobil cihazlarda bulunan GSM modülünden okunan GSM sinyal seviyeleri üzerinden ölçülmüştür. Testler lamine edilmiş kumaş yapılarının arasına cep telefonu yerleştirilerek GSM sinyal seviyesindeki değişimler izlenmiştir. Ölçülen güç değerlerine göre EMSE değerleri hesaplanmıştır.

Anahtar Kelimeler

• Metal iplik,elektromanyetik kalkanlama etkinliği; dokuma kumaş

Measurement of Electromagnetic Shielding Effectiveness of Woven Fabrics Containing Metallic Yarns by Mobile Devices

Öz

In this study, we introduce an alternative method to evaluate the electromagnetic shielding effectiveness (EMSE) of woven fabrics containing metal wires. For experimental measurements, hybrid silk viscose yarns containing metal wires were first produced. Conductive test fabrics were then produced using the hybrid weft yarns and polyester warp yarns. The produced fabrics were separated in two parts and laminated together after rotating one fabric by 90 degrees to create a grid structure. The laminated fabrics were then folded by several times to create multiple layers such as 2,4,8,12,16. The EMSE of the multiple layered fabrics was measured over GSM signals received by a mobile device. For EMSE evaluation, the mobile device was placed between the laminated fabrics. The EMSE values of the fabrics were then calculated in accordance with the power variations of GSM signals.

Anahtar Kelimeler

• Metallic yarn,electromagnetic shielding effectiveness; woven fabrics

Kaynakça

1. Acar, M. and Yalçın, U. (2010). 4G new generation LTE GSM base station antenna design. Uludağ University Journal of The Faculty of Engineering and Architecture, 15(2), 23–29.
2. Akopian, V. and Chirkov, A. (1999). EMI shielding fabric and fabric articles made therefrom. US Patent 5,968,854.
3. Bonaldi, R. R., Siores, E., and Shah, T. (2010). Electromagnetic shielding characterisation of several conductive fabrics for medical applications. Journal of Fiber Bioengineering and Informatics, 2(4), 245–253. http://doi.org/10.3993/jfbi03201006
4. Chen, H. C., Lee, K. C., Lin, J. H., and Koch, M. (2007). Fabrication of conductive woven fabric and analysis of electromagnetic shielding via measurement and empirical equation. Journal of Materials Processing Technology, 184(1-3), 124–130. http://doi.org/10.1016/j.jmatprotec.2006.11.030
5. Geetha, S., Kumar, K. K. S., Rao, C. R. K., Vijayan, M., and Trivedi, D. C. (2009). EMI shielding: methods and materials-a review. Journal of Applied Polymer Science, 112(1), 2073–2086.
6. Halonen, T., Romero, J., and Melero, J. (2004). GSM, GPRS and EDGE performance: evolution towards 3G/UMTS.
7. Lin, J. H., Lou, C. W., and Liu, H. H. (2007). Process and anti-electrostatic properties of knitted fabric made from hybrid staple/metallic-core spun yarn. Journal of Advanced Materials, 39(1), 11–16.
8. Lou, C.-W. (2005). Process of complex core spun yarn containing a metal wire. Textile Research Journal, 75(6), 466–473. http://doi.org/10.1177/0040517505053871

9. Roh, J.-S., Chi, Y.-S., Tae Jin Kang, and Nam, S. (2008). Electromagnetic shielding effectiveness of multifunctional metal composite fabrics. Textile Research Journal, 78(9), 825–835. http://doi.org/10.1177/0040517507089748
10. Umul, Y. Z., and Yalçin, U. (2010). Scattered fields of conducting half-plane between two dielectric media. Applied Optics, 49(20), 4010–7. http://doi.org/10.1364/AO.49.004010
11. Varnaite, S., Vitkauskas, A., Abraitiene, A., Rubeziene, V., and Valiene, V. (2008). The features of electric charge decay in the polyester fabric containing metal fibres. Medziagotyra, 14(2), 157–161.