A conical horn antenna fed by a cavity-backed two-layered suspended microstrip antenna has been proposed. The overall compact antenna with a length of 2.3λ0 yields a wide impedance bandwidth of 57% centred around 2.8 GHz with a very high gain of 19.9 dBi, an average gain of 17.5 dBi and a radiation efficiency of above 88%. In effect, the gain of the basic two-layered suspended microstrip antenna is enhanced by 8.4 dB when it is backed by the cavity and the conical horn. A good radiation characteristic is obtained throughout the impedance bandwidth with main beam stability, high isolation between two such antennas and low cross-polarization. Over the entire operating bandwidth cross-polarization lower than -30 dB with co-cross polarization isolation better than 50 dB is obtained in 45˚ plane. In comparison to conventional conical horn antennas yielding the same gain, the proposed antenna is more efficient with only 45% length. The prime contribution of the work is the concurrent yield of high 19.9 dBi gain, wide bandwidth, high efficiency and good radiation characteristics including unidirectional stable radiation patterns, low cross pol. and high isolation between antennas which has not been reported so far. The proposed antenna is designed for various S-band FMCW Radars.
2. Balanis, C. A., Antenna Theory: Analysis and Design, 739, John Wiley and Sons, USA, 2005.
3. Oliver, A. D., P. J. B. Clarricoats, A. A. Kishk, and L. Shafai, Microwave Horns and Feeds, ser. Electromagnetic Wave, Vol. 39, Inst. Elect. Eng., London, UK, 1994.
4. Matin, M. A., B. S. Sharif, and C. C. Tsimenidis, "Broadband stacked microstrip antennas with different radiating patch," Wirel. Pers. Commun., Vol. 56, 637-648, 2011, doi: 10.1007/s11277-009-9836-7.
5. Kumar, G. and K. P. Ray, Broadband Microstrip Antenna, 106-188, Artech House, USA, 2003.
6. Raha, K. and K. P. Ray, "Development of multi cavity-backed stacked multi-resonator microstrip antenna," IETE J. Res., Taylor and Francis, Jul. 26, 2022, doi: 10.1080/03772063.2022.2098835.
7. Kumar, G., K. P. Ray, and A. A. Deshmukh, "Microstrip antenna integrated with horn antenna," Int. J. Microw. Opt. Technol., Vol. 1, No. 1, 2006.
8. Shireen, R., T. Hwang, S. Shi, and D. W. Prather, "Stacked patch excited horn antenna at 94 GHz," Microw. Opt. Technol. Lett., Vol. 50, 2071-2074, 2008, doi: 10.1002/mop.23562.
9. Elboushi, A. and A. Sebak, "High-gain hybrid microstrip/conical horn antenna for MMW applications," IEEE Antennas Wirel. Propag. Lett., Vol. 11, 129-132, 2012, doi: 10.1109/LAWP.2012.2184256.
10. Sethi, W. T., H. Vettikalladi, B. K. Minhas, and M. A. Alkanhal, "High gain and wide-band aperture-coupled microstrip patch antenna with mounted horn integrated on FR4 for 60 GHz communication systems," IEEE Symp. Wirel. Technol. Appl. (ISWTA), 359-362, 2013, doi: 10.1109/ISWTA.2013.6688804.
11. Nuangpirom, P., E. Pruksawan, and S. Akatimagool, "The development of high gain waveguide antennas for Wi-Fi communication system," Int. Elect. Eng. Congress (iEECON), 1-4, Thailand, 2017, doi: 10.1109/IEECON.2017.8075834.
12. Fadzil, M., A. Othman, and Z. A. Ahmad, "Hybrid dielectric resonator integrated pyramidal horn antenna," Microw. Opt. Technol. Lett., Vol. 55, No. 6, 1299-1303, 2013.
13. Gupta, R. D. and M. S. Parihar, "Differentially fed wideband rectangular DRA with high gain using short horn," IEEE Antennas Wirel. Propag. Lett., Vol. 16, 1804-1807, 2017, doi: 10.1109/LAWP.2017.2679228.
14. Jang, T. H., H. Y. Kim, and C. S. Park, "A 60 GHz wideband switched-beam dipole-array-fed hybrid horn antenna," IEEE Antennas Wirel. Propag. Lett., Vol. 17, No. 7, 1344-1348, Jul. 2018, doi: 10.1109/LAWP.2018.2845877.
15. Lim, T. H., J. Park, and H. Choo, "Design of a vivaldi-fed hybrid horn antenna for low-frequency gain enhancement," IEEE Trans. Antennas and Propag., Vol. 66, No. 1, 438-443, Jan. 2018, doi: 10.1109/TAP.2017.2776608.
16. Pan, Y., Y. Cheng, and Y. Dong, "Dual-polarized directive ultrawideband antenna integrated with horn and vivaldi array," IEEE Antennas Wirel. Propag. Lett., Vol. 20, No. 1, 48-52, Jan. 2021, doi: 10.1109/LAWP.2020.3039377.
17. Ali, M. M. M., O. M. Haraz, and T. A. Denidni, "Millimeter-wave PRGW ME dipole antenna with surface mounted conical horn for 5G/6G applications," IEEE Int. Symp. Antennas and Propag. and USNC-URSI Radio Science Meeting (APS/URSI), 157-158, 2021, doi: 10.1109/APS/URSI47566.2021.9703972.
18. Raha, K. and K. P. Ray, "Broadband high gain and low cross-polarization double cavity-backed stacked microstrip antenna," IEEE Trans. Antennas and Propag., Vol. 70, No. 7, Jan. 2022, doi: 10.1109/TAP.2022.3140349.
19. Kraus, J. D., R. J Marhefka, and A. S. Khan, Antennas for All Applications, 3rd Ed., 329, Tata McGraw Hill, New York, 2006.
20. Karami-Raviz, A. and S. E. Hosseini, "A novel horn antenna with a bed of nails with high gain and low side lobes," 28th Iranian Conf. on Electrical Eng. (ICEE), 1-4, 2020, doi: 10.1109/ICEE50131.2020.9260938.
21. Liu, H., F. Zhang, and J. Xu, "A KA-band high gain and broadband circularly polarized horn antenna," Int. Conf. Microw. and Millimeter Wave Technol. (ICMMT), 1-3, 2020, doi: 10.1109/ICMMT49418.2020.9386816.
22. Lin, W., Z. Y. Zhang, and G. Fu, "Design of a high gain and low cross-polarization tri-band horn antenna," Int. Conf. on Microw. and Millimeter Wave Technol. (ICMMT), 1-3, 2018, doi: 10.1109/ICMMT.2018.8563910.
23. Wu, Z., Y. Bo, and S. Wu, "A spline-profile smooth-walled horn with low cross-polarization and low sidelobe," 5th Int. Conf. on Smart Grid and Electrical Automation (ICSGEA), 551-553, 2020, doi: 10.1109/ICSGEA51094.2020.00125.
24. Sozio, V., et al., "Design and realization of a low cross-polarization conical horn with thin metasurface walls," IEEE Trans. Antennas and Propag., Vol. 68, No. 5, 3477-3486, May 2020, doi: 10.1109/TAP.2020.2975253.
25. Chen, Y. C., et al., "A dual-polarized improved gaussian profiled corrugated horn antenna with low cross-polarization," Int. Conf. Microw. and Millimeter Wave Technol. (ICMMT), 1-3, 2021, doi: 10.1109/ICMMT52847.2021.9618208.
26. Zhang, R., G. Lu, Q. Guo, D. Zeng, Z. Cao, and C. Chen, "Optimization of corrugated profiled horn with low cross-polarization," IEEE 5th Int. Symp. on Electromagnetic Compatibility, 1-3, Beijing, 2017, doi: 10.1109/EMC-B.2017.8260436.
27. Zhang, R. and G. Lu, "Design of corrugated horn with low cross-polarization and wide band for satellite applications," 26th IEEE Asia-Pacific Conf. on Comn. (APCC), 179-184, 2021, doi: 10.1109/APCC49754.2021.9609873.
28. Raha, K. and K. P. Ray, "Low cost simple compact and portable ground penetrating radar prototype for detecting improvised explosion devices," Intelligent Electronics and Circuits - Terahertz, IRS, and Beyond, Dr. Mingbo Niu, Ed., Intechopen, London, May 24, 2022, doi: 10.5772/intechopen.104744.