An objective of the present study is to make a physical insight into the radiation properties of an L-shaped wire antenna. More specifically, the study is focused on the effects of the antenna geometry over the characteristic radiation pattern of an L-shaped wire antenna. Regarding the basic equations for the radiated field, three main regions according to the length-height ratio of an L-shaped wire antenna have been determined. The said regions depict the geometrical boundaries where the L-shaped wire antenna loses its characteristic monopoletype radiation pattern. In this sense and relating to the aspect ratio of the L-shaped antenna, the said radiation properties can be easily varied in order to achieve a half isotropic radiation pattern or even, a patch-type radiation pattern. Thus, the method described herein demonstrates that simple modifications applied to the geometry of a basic structure, allow obtaining radiation properties associated to more complex structures.
2. King, R., C. W. Harrison, and D. H. Denton, "Transmission-line missile antennas," IEEE Transactions on Antennas and Propagation, Vol. 8, No. 1, 88-90, January 1960.
3. Simpson, T. L., "The theory of top-loaded antennas: Integral equations for the currents," IEEE Transactions on Antennas and Propagation, Vol. 19, No. 2, 186-190, March 1971.
4. Guertler, R. J. F., "Isotropic transmission line antenna and its toroid-pattern modification," IEEE Transactions on Antennas and Propagation, Vol. 25, No. 3, 386-392, May 1997.
5. Hansen, R. C., "Effects of a high-impedance screen on a dipole antenna," IEEE Antennas and Wireless Propagation Letters, Vol. 1, 46-49, 2002.
6. Chen, H. T., J. X. Luo, and D. K. Zhang, "An analytic formula of the current distribution for the VLF horizontal wire antenna above lossy half-space," Progress In Electromagnetics Research Letters, Vol. 1, 149-158, 2008.
7. Green, H. E. and J. D. Cashman, "The transmission line antenna revisited," IEEE Transaction on Antennas and Propagation, Vol. 38, No. 4, 575-578, April 1990.
8. Balanis, C. A., Antenna Theory Analysis and Design, 2 Ed., No. 4, 133-203, John Wiley & Sons, 1997.
9. Rogers, S. D., C. M. Butler, and A. Q. Martin, "Design and realization of GA-optimized wire monopole and matching network with 20 : 1 bandwidth," IEEE Transaction on Antennas and Propagation, Vol. 51, No. 3, 493-502, March 2003.
10. Long, S. A., "A combination of linear and slot antennas for quasi-isotropic coverage," IEEE Transaction on Antennas and Propagation, 572-576, July 1975.
11. Mehdipour, A., H. Aliakbarian, and J. Rashed-Mohassel, "A novel electrically small spherical wire antenna with almost isotropic radiation pattern," IEEE Antennas and Wireless Propagation Letters, Vol. 7, 396-399, 2008.