Vol. 61

Front:[PDF file] Back:[PDF file]
Latest Volume
All Volumes
All Issues

Flexible Antennas Based on Natural Rubber

By Zaiki Awang, Nur Adyani Mohd Affendi, Nur Aimi Liyana Alias, and Nur Azlin Mohd Razali
Progress In Electromagnetics Research C, Vol. 61, 75-90, 2016


Flexible substrates have been increasingly studied in recent years. This paper proposes natural rubber as a new substrate material for flexible antennas. In our work, prototype antennas were built using rubber formulated with different filler contents. Carbon black was used as the filler where its amount was varied to yield different dielectric properties. Prototype inset-feed microstrip patch antennas with outer dimensions 7.52 mm × 10.607 mm × 1.7 mm and copper as its conducting material were fabricated to operate at 2.45 GHz. The prototypes were measured and their performance analyzed in terms of the effects of filler content on Q, return loss and bending effects on their gain and radiation characteristics. The return loss and gain were found to be comparable to those built on existing synthetic substrates, but these new antennas offer an added feature of frequency-tunability by varying the filler content. Under bending conditions, these new antennas were also found to perform better than existing designs, showing less changes in their gain, frequency shift and beamwidth, in addition to less impedance mismatch when bent.


Zaiki Awang, Nur Adyani Mohd Affendi, Nur Aimi Liyana Alias, and Nur Azlin Mohd Razali, "Flexible Antennas Based on Natural Rubber," Progress In Electromagnetics Research C, Vol. 61, 75-90, 2016.


    1. Liyakath, R. A., A. Takshi, and G. Mumcu, "Multilayer stretchable conductors on polymer substrates for conformal and reconfigurable antennas," IEEE Antennas and Wireless Propag. Lett., Vol. 12, 603-606, 2013.

    2. Hayes, G. J., A. Qusba, M. D. Dickey, and G. Lazzi, "Flexible liquid metal alloy (EGaIn) microstrip patch antenna," IEEE Trans. Antennas Propag., Vol. 60, No. 5, 2151-2156, May 2012.

    3. Hazra, R., C. K. Ghosh, and S. K. Parui, "Effect of different semi conductive substrate materials on a P-shaped wearable antenna," Int. J. of Adv. Res. in Comp. and Comm. Eng. (IJARCCE), Vol. 2, No. 8, 3071-3074, 2013.

    4. Xi, J., H. Zhu, and T. T. Ye, "Exploration of printing-friendly RFID antenna designs on paper substrates," IEEE Int. Conf. on RFID, 38-44, April 2011.

    5. Trajkovikj, J., J. F. Zurcher, and A. K. Skrivervik, "Soft and flexible antennas on permittivity adjustable PDMS substrates," Loughborough Ant. and Prop. Conf., 1-4, November 2012.

    6. Gunasekaran, S., R. K. Natarajan, A. Kala, and R. Jagannathan, "Dielectric studies of some rubber materials at microwave frequencie," Ind. J. Pure and APhys., Vol. 46, 73-737, October 2008.

    7. Ganchev, S. I., J. Bhattacharyya, S. Bakhtiari, N. Qaddoumi, D. Brandenburg, and R. Zaughi, "Microwave diagnosis of rubber compounds," IEEE Trans. on Microw. Theory and Tech., Vol. 42, No. 1, 18-24, January 1994.

    8. Al-Hartomy, O. A., F. Al-Solamy, A. Al-Ghamdi, N. Dishovsky, V. Iliev, and F. El-Tantawy, "Dielectric and microwave properties of siloxane rubber/carbon black nano-composites and their correlatio," Int. J. Polymer Sc., Vol. 2011, 2011.

    9. Oliveira, F. A., N. Alves, J. A. Giacometti, C. J. L. Constantino, L. H. C. Mattoso, A. M. O. A. Balan, and A. E. Job, "Study of the thermomechanical and electrical properties of conducting composites containing natural rubber and carbon black," J. Appl. Polym. Sci., Vol. 106, No. 2, 1001-1006, 2007.

    10. Ohira, K., "Development of an antenna material based on rubber that has flexibility and high impact resistance," NTN Tech. Rev., No. 76, 2008.

    11. Alias, N. A. L., N. A. M. Affendi, Z. Awang, M. T. Ali, and A. Samsuri, "Preliminary studies on the use of natural rubber in the design of flexible microstrip antennas," 2013 IEEE Int. RF Microw. Conf., 454-459, Penang, December 2013.

    12. Affendi, N. A.M., N. A. L. Alias, Z. Awang, M. T. Ali, and A. Samsuri, "Microwave non-destructing testing of rubber at X-band," 2013 IEEE Int. RF Microw. Conf., 333-337, Penang, December 2013.

    13., Basics of Measuring the Dielectric Properties of Materials, Keysight Technologies ANote, Lit. No. 5989-2589EN, April 27, 2015.

    14. Balanis, C. A., "Microstrip antenna," Antenna Theory: Analysis and Design, 2nd edition, Chap. 14, 737, 760-762, John Wiley & Sons Ltd, 1997.

    15. Carver, K. R. and J. Mink, "Microstrip antenna technology," IEEE Trans. Antennas Propag., Vol. 29, No. 1, 2-24, January 1981.

    16. Laheurte, J., "Electrical equivalent circuit of a printed antenna," Compact Antennas for Wireless Communications and Terminals, 1st edition, Chap. 5, 62-68, John Wiley & Sons Ltd, 2011.

    17. Chen, Z. N. and M. Y. W. Chia, "Planar radiators," Broadband Planar Antennas, 1st edition, Chap. 1, 3-31, John Wiley & Sons Ltd, 2006.

    18. Baker-Jarvis, J., M. D. Janezic, and D. C. DeGroot, "High-frequency dielectric measurement," IEEE Trans. Instrum. Meas., Vol. 13, No. 2, 24-31, 2010.

    19. Pozar, D. M. and D. H. Schaubert, Microstrip Antennas, Wiley-IEEE Press, NewYork, 1995.

    20. Mäntysalo, M. and P. Mansikkamäki, "An inkjet-deposited antenna for 2.4 GHz applications," AEU - Int. J. Electron. Commun., Vol. 63, No. 1, 31-35, 2009.

    21. Sankaralingam, S. and B. Gupta, "Development of textile antennas for body wearable applications and investigations on their performance under bent conditions," Progress In Electromagnetics Research B, Vol. 22, 53-71, 2010.

    22. Boeykens, F., L. Vallozzi, and H. Rogier, "Cylindrical bending of deformable textile rectangular patch antennas," Int. J. of Ant. and Prop., 1-11, 2012.

    23. Reffaee, A. S. A., D. E. El Nashar, S. L. Abd-El-Messieh, and K. N. Abd-El Nour, "Electrical and mechanical properties of acrylonitrile rubber and linear low density polyethylene composites in the vicinity of the percolation threshold," Int. J. of Mat. in Eng. Applications, Vol. 30, No. 9, 3760-3769, 2009.

    24. Krowne, C. M., "Cylindrical rectangular microstrip antenna," IEEE Trans. Antennas Propag., Vol. 31, No. 1, 194-199, 1983.

    25. Bai, Q. and R. Langley, "Textile PIFA antenna bending," Loughborough Ant. and Prop. Conf., 1-4, 2011.

    26. Kumar, V., "Radiation pattern of omnidirectional conformal microstrip patch antenna on cylindrical surface," Int. J. of Emerging Tech. and Adv. Eng., Vol. 3, 483-487, February 2013.

    27. Katehi, P. B. and N. G. Alexopoulos, "On the effect of substrate thickness and permittivity on printed circuit dipole properties," IEEE Trans. Antennas Propag., Vol. 31, No. 1, 34-38, January 1983.

    28. Anaekwe, I., et al., "The effect of curvature adaptation on 2.45 GHz rectangular patch antennas," IEEE TENCON Spring Conf., 123-127, April 2013.

    29. Mansor, M. M., et al., "A 2.45 GHz wearable antenna using conductive graphene and polymer substrate," Int. Sym. on Tech. Management and Emerging Tech. (ISTMET), 29-32, May 2014.

    30. Kellomaki, T., et al., "Bendable plaster antenna for 2.45 GHz applications," Loughborough Ant. and Prop. Conf., 453-456, November 2009.