In this article, a new wideband bowtie shaped slot antenna is realized on a flexible polyethylene terephthalate (PET). The slotted bowtie design is implemented with an asymmetric bow-tie flare angle and a larger feeding neck with a metal strip inside the bowtie slot to achieve a wider bandwidth and a higher gain. The designed free space antenna is fabricated using inkjet printing and tested. The fabricated antenna operates over 2.1-4.35 GHz frequency range (69.77% fractional bandwidth) which covers WLAN, WiMax, and most of the 3G and 4G frequency bands. Further, the antenna exhibits an omnidirectional radiation pattern with a peak gain of 6.3 dBi at 4.35 GHz. The bending test of the fabricated device reveals adequate flexibility without significant antenna performance degradation. Moreover, the antenna tunability for any mounting structure application is also investigated by simulating another version of the parent antenna (free space antenna) for drywall mounting applications. The tuned antenna covers a similar frequency band as a free space antenna maintaining the desired radiation performances. The compact size, higher bandwidth, omnidirectional pattern with a higher peak gain and flexible properties make the antenna design suitable for mounting structure for Internet of Things (IoT) applications.
1. Hester, J. G. and M. M. Tentzeris, "Inkjet-printed flexible mm-wave Van-Atta reflectarrays: A solution for ultralong-range dense multitag and multisensing chipless RFID implementations for IoT smart skins," IEEE Transactions on Microwave Theory and Techniques, Vol. 64, No. 12, 4763-4773. doi:2016
2. Paracha, K. N., S. K. A. Rahim, H. T. Chattha, S. S. Aljaafreh, and Y. C. Lo, "Low-cost printed flexible antenna by using an office printer for conformal applications," International Journal of Antennas and Propagation, Vol. 2018, 1-7, 2018.
3. Li, X., M. M. Honari, Y. Fu, A. Kumar, H. Saghlatoon, P. Mousavi, and H.-J. Chung, "Self-reinforcing graphene coatings on 3D printed elastomers for flexible radio frequency antennas and strain sensors," Flexible and Printed Electronics, Vol. 2, No. 3, 035001, 2017.
4. Cosker, M., L. Lizzi, F. Ferrero, R., Staraj, and J.-M. Ribero, "Realization of 3-D flexible antennas using liquid metal and additive printing technologies," IEEE Antennas and Wireless Propagation Letters, Vol. 16, 971-974, 2016.
5. Abutarboush, H. F. and A. Shamim, "Based inkjet-printed tri-band U-slot monopole antenna for wireless applications," IEEE Antennas and Wireless Propagation Letters, Vol. 11, 1234-1237, 2012.
6. Mansour, A., N. Shehata, B. Hamza, and M. Rizk, "Efficient design of flexible and low cost paper-based inkjet-printed antenna," International Journal of Antennas and Propagation, Vol. 2015, 2015.
7. Anagnostou, D. E., A. A. Gheethan, A. K. Amert, and K. W. Whites, "A direct-write printed antenna on paper-based organic substrate for flexible displays and WLAN applications," Journal of Display Technology, Vol. 6, No. 11, 558-564, 2010.
8. Hassan, A., S. Ali, G. Hassan, J. Bae, and C. H. Lee, "Inkjet-printed antenna on thin PET substrate for dual band Wi-Fi communications," Microsystem Technologies, Vol. 23, No. 8, 3701-3709, 2017.
9. Guo, X., Y. Hang, Z. Xie, C. Wu, L. Gao, and C. Liu, "Flexible and wearable 2.45 GHz CPW-fed antenna using inkjet-printing of silver nanoparticles on pet substrate," Microwave and Optical Technology Letters, Vol. 59, No. 1, 204-208, 2017.
11. Bhaskar, V. S., E. L. Tan, and L. K. H. Holden, "Design of wideband bowtie slot antenna using sectorially modified gielis curves," IEEE Antennas and Wireless Propagation Letters, Vol. 17, No. 12, 2237-2240, 2018.
12. Mazaheri, M., N. Amani, and A. Jafargholi, "Wideband printed slot bowtie antenna using symmetric vias," Microwave and Optical Technology Letters, Vol. 58, No. 6, 1301-1304, 2016.
13. Pierce, R. G., A. J. Blanchard, and R. M. Henderson, "Broadband planar modified aperture bowtie antenna," IEEE Antennas and Wireless Propagation Letters, Vol. 12, 1432-1435, 2013.
14. Tsai, L.-C., "A triple-band bow-tie-shaped CPW-fed slot antenna for WLAN applications," Progress In Electromagnetics Research C, Vol. 47, 167-171, 2014.
15. Xu, L., L. Li, and W. Zhang, "Study and design of broadband bowtie slot antenna fed with asymmetric CPW," IEEE Transactions on Antennas and Propagation, Vol. 63, No. 2, 760-765, 2014.
16. Chen, Y.-L., C.-L. Ruan, and L. Peng, "A novel ultra-wideband bow-tie slot antenna in wireless communication systems," Progress In Electromagnetics Research Letters, Vol. 1, 101-108, 2008.
17. Yoon, J. H. and Y. C. Lee, "Modified bowtie slot antenna for the 2.4/5.2/5.8 GHz WLAN bands with a rectangular tuning stub," Microwave and Optical Technology Letters, Vol. 53, No. 1, 126-130, 2011.
18. Dayo, Z. A., Q. Cao, P. Soothar, M. M. Lodro, and Y. Li, A Compact Coplanar Waveguide Feed Bowtie Slot Antenna for WIMAX, C and X Band Applications, 1-3, IEEE, 2019.
19. Yamamoto, M. and T. Nojima, Design of a Leaf-shaped Bowtie Slot Antenna Electromagnetically Fed by a Microstrip Line, 261-262, IEEE, 2014.
20. Sagnard, F. and F. Rejiba, "Wide band coplanar waveguide-fed bowtie slot antenna for a large range of ground penetrating radar applications," IET Microwaves, Antennas and Propagation, Vol. 5, No. 6, 734-739, 2011.
21. Sallam, M. O., S. M. Kandil, V. Volski, G. A. Vandenbosch, and E. A. Soliman, "Wideband CPW-fed flexible bowtie slot antenna for WLAN/WiMax systems," IEEE Transactions on Antennas and Propagation, Vol. 65, No. 8, 4274-4277, 2017.
22. Liu, H., S. Zhu, P. Wen, X. Xiao, W. Che, and X. Guan, "Flexible CPW-fed fishtail-shaped antenna for dual-band applications," IEEE Antennas and Wireless Propagation Letters, Vol. 13, 770-773, 2014.
23. Sahoo, R. and D. Vakula, "Bow-tie-shaped wideband conformal antenna with wide-slot for GPS application," Turkish Journal of Electrical Engineering & Computer Sciences, Vol. 27, No. 1, 80-93, 2019.
24. Durgun, A. C., M. S. Reese, C. A. Balanis, C. R. Birtcher, D. R. Allee, and S. Venugopal, Book Flexible Bowtie Antennas with Reduced Metallization, 50-53, IEEE, 2011.
25. Farooqui, M. F. and A. Shamim, Dual Band Inkjet Printed Bowtie Slot Antenna on Leather, 3287-3290, IEEE, 2013.
26. Choudhary, E., S. Sharma, and P. Yadav, A Modified Wideband Bow-tie Antenna with DGS for Wireless Fidelity Range, 1-5, IEEE, 2018.
27. Salonen, P., J. Kim, and Y. Rahmat-Samii, Dual-band E-shaped Patch Wearable Textile Antenna, 466-469, IEEE, 2005.
28. Singh, N., A. K. Singh, and V. K. Singh, "Design and performance of wearable ultrawide band textile antenna for medical applications," Microwave and Optical Technology Letters, Vol. 57, No. 7, 1553-1557, 2015.
29. Krykpayev, B., M. F. Farooqui, R. M. Bilal, M. Vaseem, and A. Shamim, "A wearable tracking device inkjet-printed on textile," Microelectronics Journal, Vol. 65, 40-48, 2017.
30. Mansour, A., M. Azab, and N. Shehata, Flexible Paper-based Wideband Antenna for Compact-size IoT Devices, 426-429, IEEE, 2017.
31. Zahran, S. R., Z. Hu, and M. A. Abdalla, A Flexible Circular Polarized Wide Band Slot Antenna for Indoor IoT Applications, 1163-1164, IEEE, 2017.
32. Lee, C.-H., S.-Y. Chen, and P. Hsu, Compact Modified Bowtie Slot Antenna Fed by CPW for Ultra-wideband Applications, 1-4, IEEE, 2009.
33. Qu, S.-W. and C.-L. Ruan, "Effect of round corners on bowtie antennas," Progress In Electromagnetics Research, Vol. 57, 179-195, 2006.
34. Saha, T. K., T. N. Knaus, A. Khosla, and P. K. Sekhar, "A CPW-fed flexible UWB antenna for IoT applications," Microsystem Technologies, 1-7, 2018.
35. Elobaid, H. A. E., S. K. A. Rahim, M. Himdi, X. Castel, and M. A. Kasgari, "A transparent and flexible polymer-fabric tissue UWB antenna for future wireless networks," IEEE Antennas and Wireless Propagation Letters, Vol. 16, 1333-1336, 2016.
36. Jilani, S. F. and A. Alomainy, Planar Millimeter-wave Antenna on Low-cost Flexible PET Substrate for 5G Applications, 1-3, IEEE, 2016.
37. Lee, C. M., Y. Kim, Y. Kim, I. K. Kim, and C. W. Jung, "A flexible and transparent antenna on a polyamide substrate for laptop computers," Microwave and Optical Technology Letters, Vol. 57, No. 5, 1038-1042, 2015.
38. Riheen, M. A., T. K. Saha, and P. K. Sekhar, "Inkjet printing on PET substrate," Journal of the Electrochemical Society, Vol. 166, No. 9, B3036-B3039, 2019.
39. Saha, T. K., C. Goodbody, T. Karacolak, and P. K. Sekhar, "A compact monopole antenna for ultra-wideband applications," Microwave and Optical Technology Letters, Vol. 61, No. 1, 182-186, 2019.
40. De Cos Gomez, M., H. F. Alvarez, C. G. Gonzalez, B. P. Valcarce, J. Olenick, and F. Las-Heras, Ultra-thin Compact Flexible Antenna for IoT Applications, 1-4, IEEE, 2019.
41. Katehi, P. and N. Alexopoulos, "On the effect of substrate thickness and permittivity on printed circuit dipole properties," IEEE Transactions on Antennas and Propagation, Vol. 31, No. 1, 34-39, 1983.
42. Thajudeen, C., A. Hoorfar, F. Ahmad, and T. Dogaru, "Measured complex permittivity of walls with different hydration levels and the effect on power estimation of TWRI target returns," Progress In Electromagnetics Research B, Vol. 30, 177-199, 2011.
43. Common, L. T., Propagation losses through common building materials 2.4 GHz vs 5 GHz, E10589, Magis Network, Inc., 2002.