Low-cost microstrip patch array antenna for X band satellite applications

In this thesis, the aim of the design a microstrip patch array antenna that operate between 7.25 GHz and 8.4 GHz frequencies for VSAT satellite communication so VSAT structure and array antenna structures which are used and designed in the literature are examined in detail. The bow tie antenna has been studied as the first design can produce broadband results. S11 parameter was expected to be at least -10 dB in the desired frequency range, but the result was observed as -7 dB. Therefore, this design was decided to be completely replaced. In order to obtain a better result in the desired frequency range S11 parameter, a new design has been obtained by applying the "proximity coupling" method which is used for this purpose in the literature. But this method is not allow us to reach the desired results. After these results, due to the complexity of bow tie antennas, it is decided to design a microstrip square patch antenna which is easier to design in the literature rather than this type of antenna. It was observed that the results were better than the previous designs in the S11 parameter values in the desired frequency range. In the antenna structures designed in the literature, the radiation patterns occur in the middle of the antenna. However, the main problem in this design is that the pattern of radiation is exposed in the upper right lobe and upper left lobes of the antenna. This design should be positioned vertical in the area used for realization and use. However, in order to increase the applicability of the design, horizontal positioning is of great importance so improvement of this design has been abandoned. In the final stage of the thesis study, microstrip square patch antenna which is the basic structure was designed with the addition of a proximity coupling system to operate in the desired frequency range. This latest design has a radiation pattern in the center of the antenna and operates in the desired frequency range in the X-band. The desired radiation pattern is reached at the desired frequencies so it has began study to increase the gain. In order to increase the gain, the array antenna design was replicated. Four, eight and sixteen patch array antenna designs were realized, respectively. The desired results were successfully reached by the simulation on CST software.