Analysis and design of a circularly polarized microstrip antenna

Taştan, Mehmet
In this study we tried to design a microstrip antenna, to get a suitable radiation pattern for a LEO satellite. Our aim is to get a radiation pattern that has a maximum power which is not in the broadside direction to the antenna surface; instead broadside radiation has a relatively lower power density. Maximum power radiation is desired to be at about 30 50 degrees angle beyond the normal to the antenna surface. We desire circularly polarized radiation. We used two concentric antennas; one is a circular patch at the center and the other is an annular ring which is used at the outer region. By using Ansoft Ensemble 8.0 software, we design an antenna which has a resonance frequency at 8.2 GHz. Using the result of the program we design the real antenna. The measurement results are compared with the simulation results.


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Method of Moments (MoM)/Green’s function formulation is developed for the analysis of electromagnetic radiation from planar rectangular microstrip antennas with different feeding techniques. Investigated structures are microstrip line fed patch antenna, proximity coupled patch antenna and slot coupled patch antenna. For all these structures equivalent problems are defined. Then, integral equations where currents are the unknowns are obtained from boundary conditions and by using spectral domain representati...
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Citation Formats
M. Taştan, “Analysis and design of a circularly polarized microstrip antenna,” M.S. - Master of Science, Middle East Technical University, 2006.