Aiming at the bandwidth enhancement for patch antennas, a new impedance matching scheme is presented. In this design, open-ended microstrip-lines are used as the matching resonators; the gaps between the lines are used as the J inverters. Numerical and experimental studies are executed to demonstrate this new structure. The measured and predicted results are in good agreement. The measured data show that the bandwidth of a sample antenna is increased by a factor of 3.3 after adding two matching resonators. The proposed matching structure is good in performance, and smaller in size than traditional matching structures.
2. Kumar, G. and K. Ray, Broadband Microstrip Antennas Norwood, Artech House, MA, 2003.
3. Sabban, A., A new broadband stacked two-layer microstrip antenna, IEEE AP-S Int. Symp. Digest, 63-66, 1983.
4. Wood, C., "Improved bandwidth of microstrip antennas using parasitic elements," Proc. IEE, Microwaves, Optics and Antennas, Vol. 127, 231-234, 1980.
5. Guo, Y. X., K. M. Luk, K. F. Lee, and Y. L. Chow, "Double U-slot rectangular microstrip antenna," Electronics Letters, Vol. 34, 1805-1806, 1998.
6. Luk, K. M., X. Guo, K. F. Lee, and Y. L. Chow, "L-probe proximity fed U-slot patch antenna," Electronics Letters, Vol. 34, 1806-1807, 1998.
7. Huang, K. C. and H. F. Li, "A novel single-layer single-patch wide-band probe-feed crescentlike-shaped microstrip antenna," Journal of Electromagnetics Waves and Applications, Vol. 23, 279-287, 2009.
8. Shi, S. J., L. H. Weng, Y. Y. Yang, X. Q. Chen, and X. W. Shi, "Design of wideband dissymmetric E-shaped microstrip patch antenna," Journal of Electromagnetics Waves and Applications, Vol. 23, 645-654, 2009.
9. Pues, H. G. and A. R. Van de Capelle, "An impedance matching technique for increasing the bandwidth of microstrip antennas," IEEE Trans. Antennas Propagation, Vol. 37, 1345-1354, 1989.
10. An, H. M., B. K. J. C. Nauwelaers, and A. R. Van de Capelle, "Broadband microstrip antenna design with the simplified real frequency technique," IEEE Trans. Antennas Propagation.
11. Kim, J. I. and Y. J. Yoon, "Design of wideband microstrip array antennas using the coupled lines ," IEEE AP-S Int. Symp. Digest, 1410-1413, 2000.
12. Kim, I. K., J. I. Kim, S. Pinel, J. Laskar, M. M. Tentzeris, and J. G. Yook, Novel feeding topologies for 2nd harmonic suppression in broadband microstrip patch antennas, IEEE AP-S Int. Symp., 1483-1486, 2006.
13. Abunjaileh, A. I., I. C. Hunter, and A. H. Kemp, "A circuit theoretic approach to the design of quadruple-mode broadband microstrip patch antennas," IEEE Trans. Microwave Theory and Techniques, Vol. 56, 896-900, 2008.
14. Abdelaziz, A. A., "Bandwidth enhancement of microstrip antenna," Progress In Electromagnetics Research, Vol. 63, 311-317, 2006.
15. Matthaei, G. L., L. Young, and E. M. T. Jones, Microwave Filters, Impedance-matching Networks, and Coupling Structures, Sec. 4.09-4.10, McGraw-Hill, New York, 1980.
16. Hong, J. S. and M. J. Lancaster, "Microstrip Filters for RF/Microwave Applications," Wiley, New York, 2001, 150-153.