The project is about the design and manufacturing of two circular polarized antennas in microstrip (clockwise and counterclockwise). The group of antennas is performed by linearly polarized rectangular elements. For designing has been used the software Advanced Design System (ADS) and HFSS (High Frequency Structural Simulator). The target is to achieve the manufacturing of two antennas with the necessary parameters to apply them in a real aperture radar, used to measure vibrations and small displacements of different structures. The purpose is to improve the current results of the radar measurements using the circular polarization. Therefore, the main parameter to consider is the quality of circular polarization within the frequency range in which it operates the radar, and it is between 16.9 and 17.3 GHz. The report content follows the procedure used to accomplish the objective. The introductory chapter is about designing a rectangular microstrip antenna with linear polarization, including the selection of the dielectric substrate, the calculation of the antenna size and the simulated results after optimization. The next chapter explains the theory applied to get a circular polarization by a group of linear polarized antennas. Once explained the concept of the sequential rotation, in the third chapter is designed the transmission lines network to feed the antenna group from a single point, getting the final design of both antennas. In this section is also shown the different simulations results. The project ends with the manufacturing of two microstrip antennas and showing the results of measurements.