In this paper, a novel multiband microstrip patch antenna with small frequency ratio is designed and analysed. One can design a multiband antenna at any desired frequencies through these proposed methods. The proposed antenna shows six operating frequencies with very small frequency ratio between two consecutive resonant frequency 1.1248, 1.1123, 1.0792, 1.1469 and 1.3254 and can be used for various wireless applications i.e. 2.5 GHz for UMTS and Wi-Fi, 2.812 GHz for CCTV with wireless video links, 3.128 GHz and 3.376 GHz for WiMAX, 3.872 GHz for C-band applications and 5.132 GHz for Lower WLAN. Design procedure and formation of all six bands are presented and discussed. Analysis is done by Ansoft HFSS v.15 which is based on Finite Element Method (FEM), and simulated results are verified with experimental results of fabricated prototypes which are found in close agreement.
2. Hirisawa, K. and M. Haneishi, Analysis, Design and Measurement of Small and Low-profile Antennas, 21-56, Norwood, MA Artech House, Boston, 1992.
3. Nasimuddin, Z. N. Chen and X. Qing, "Dual-band circularly polarized S-shaped slotted patch antenna with a small frequency-ratio," IEEE Transactions on Antennas and Prop., Vol. 58, 2112-2115, 2010.
4. Bao, X. L. and M. J. Ammann, "Dual-band circularly polarized patch antenna with compact size and small frequency ratio," IEEE Transactions on Antennas and Prop., Vol. 55, 2104-2107, 2007.
5. Kumar, S., M. K. Khandelwal, B. K. Kanaujia, and A. K. Gautam, "Stacked dual-band circularly polarized microstrip antenna with small frequency ratio," Microwave and Optical Technology Lett., Vol. 56, 1933-1937, 2014.
6. Kumar, S., M. K. Khandelwal, B. K. Kanaujia, and A. K. Gautam, "Single-feed circularly polarized stacked patch antenna with small frequency ratio for dual-band wireless applications," International Journal of Microwave & Wireless Technol., 1-7, 2015.
7. Khanam, F., S. R. Mitra, Md. S. Hossain, and D. K. Karmokar, "Multiband low profile modified inverted-FL strip antenna for 5.2/5.8GHz WLAN and 5.5 GHz WiMAX applications in laptop computer," 15th ICCIT 2012, 22-24, University of Chittagong, 2012.
8. Chaimool, S. and P. Akkaraekthalin, "CPW-fed antennas for Wi-Fi and WiMAX," InTech., Chapters, 22-24, 2012.
9. Forouzannezhad, P., A. Jafargholi, and A. Jahanbakhshi, "Multiband compact antenna for near-field and far-field RFID and wireless portable applications," IET Microwaves, Antennas & Propagation, Vol. 11, No. 4, 535-541, 2017.
10. Gautam, A. K. and B. K. Kanaujia, "A novel dual-band asymmetric slit with defected ground structure microstrip antenna for Circular Polarization operation," Microwave and Optical Technology Lett., Vol. 55, 1198-1201, 2013.
11. Mao, C. X., S. Gao, Y. Wang, and B. Sanz-Izquierdo, "A novel multiband directional antenna for wireless communications," IEEE Antennas and Wireless Propagation Letters, Vol. 16, 1217-1220, 2017.
12. Balanis, C. A., Antenna Theory: Analysis and Design, 3rd Ed., 816-856, John Wiley, Hoboken, NJ, 2005.
13. Shrivastava, M. K., A. K. Gautam, and B. K. Kanaujia, "An M-shaped monopole-like slot UWB antenna," Microwave and Optical Technology Lett., Vol. 56, 127-131, 2014.
14. Khandelwal, M. K., et al., "Analysis and design of wide band Microstrip-line-fed antenna with defected ground structure for Ku band applications," AEU --- International Journal of Electronics and Comm., Vol. 68, 951-957, 2014.
15. Li, T., H. Zhai, G. Li, L. Li, and C. Liang, "Compact UWB band-notched antenna design using interdigital capacitance loading loop resonator," IEEE Antennas and Wireless Propa. Lett., Vol. 11, 724-727, 2012.
16. Peng, Y. and W. X. Zhang, "Compact sub-wavelength microstrip band-reject filter based on interdigital capacitance loaded loop resonators," Micro. Opt. Technol. Lett., Vol. 52, 2656-2658, 2010.
17. Lin, X. Q. and T. J. Cui, "Controlling the bandwidth of split ring resonators," IEEE Microw. Wireless Compon. Lett., Vol. 18, 245-247, 2008.
18. Siddiqui, J. Y., et al., "Compact SRR loaded UWB circular monopole antenna with frequency notch characteristics," IEEE Transactions on Antennas and Propa., Vol. 62, 4015-4020, 2014.
19. Takemura, N., "Inverted-FL antenna with self-complementary structure," IEEE Transactions on Antenna and Propa., Vol. 57, 3029-3034, 2009.
20. Wang, Z., R. She, J. Han, S. Fang, and Y. Liu, "Dual-band dual-sense circularly polarized stacked patch antenna with a small frequency ratio for UHF RFID reader applications," IEEE Access, Vol. 5, 15260-15270, 2017.
21. Jardon-Aguilar, H., J. A. Tirado-Mendez, R. Pena-Rivero, and R. Flores-Leal, "Multiband-multislot planar antenna based on small loop-radiator," Journal of Electromagnetic Waves and Applications, Vol. 29, No. 15, 2066-2079, 2015.
22. Sethi, W. T., H. Vettikalladi, H. Fathallah, and M. Himdi, "Hexa-band printed monopole antenna for wireless applications," Microw. Opt. Technol. Lett., Vol. 59, 2816-2822, 2017.