A new antenna structure with lower side lobe pattern and higher gain was designed by combining a microstrip rectangular planar antenna array with the separated feed network technique. In this paper, the side lobe behaviors of two different radiating structures have been studied and compared. The first antenna configuration ("Structure 1") is a 16-element planar antenna array whose feed line is printed on the same plane as the radiating elements. The second one ("Structure 2") is a 16-element planar antenna array whose feed network is separated from the radiating elements by an air gap. This technique enables one to reduce the unwanted spurious effects from the feed line. Both antennas are designed at 5.8 GHz. Compared to "Structure 1" we show that the optimization of "Structure 2" allows reducing the side lobe level and increasing the antenna gain. The experimental results are shown to be in very good agreement with the numerical simulations.
2. Balanis, C. A., Antenna Theory, Analysis and Design, 3 Ed., John Wiley & Sons, New York, 2005.
3. Pozar, D. M., "Microstrip antennas," Proceedings of the IEEE, Vol. 80, 79-91, 1992.
4. Bogosanovic, M. and A. G. Williamson, "Microstrip antenna array with a beam focused in the near-field zone for application in noncontact microwave industrial inspection," IEEE Transactions on Instrumentation and Measurement, Vol. 56, 2186-2195, 2007.
5. Leon, G., R. R. Boix, M. J. Freire, and F. Medina, "Characteristics of aperture coupled microstrip antennas on magnetized ferrite," IEEE Transactions on Antennas and Propagation, Vol. 53, 1957-1966, 2005.
6. Choi, W., J. M. Kim, J. H. Bae, and C. Pyo, "High gain and broadband microstrip array antenna using combined structure of corporate and series feeding," IEEE Antennas and Propagation Society International Symposium, Vol. 3, 2484-2487, 2004.
7. Levine, E., G. Malamud, S. Shtrikman, and D. Treves, "A study of microstrip array antennas with the feed network," IEEE Transactions on Antennas and Propagation, Vol. 37, 426-434, 1989.
8. Chen, W., M. Fan, Q. Hao, and Z. Feng, "A novel reconfigurable discrete antenna," IEEE Antennas and Propagation Society International Symposium, Vol. 1, 411-414, 2003.
9. Hall, P. S., "Coplanar corporate feed effects in microstrip patch array design," IEE Proc. H: Microw. Antennas Propag., Vol. 135, No. 3, 180-186, 1988.
10. Lee, K. F. and W. Chen, Advances in Microstrip and Printed Antennas, A wiley interscience publication, 1997.
11. Das, N. K. and D. M. Pozar, "Printed antennas in multiple layers: general considerations and infinite array analysis by a unified method," Sixth International Conference on (Conf. Publ. No.301) ICAP 89, Vol. 1, 364-368, 1989.
12. Abd Rahim, M. K., A. Asrokin, M. H. Jamaluddin, M. R. Ahmad, T. Masri, and M. Z. A. A. Aziz, "Microstrip patch antenna array at 5.8 GHz for point to point communication," RF and Microwave Conference, 216-219, 2006.
13. Paul, S. H., "Multiband reconfigurable synthetic aperture radar antenna," Paper B1P1, ESTC 2004 Proceedings (CD), Palo Alto CA, June 2004.