Diseño e implementación de un sistema de medición para obtener el patrón de radiación de antenas utilizando un analizador de redes vectoriales.

Abstract

The objective of this degree work was to design and implement a measurement system to obtain the radiation pattern of antennas using a vector network analyzer (VNA). For this, the main characteristics of each of the equipment and the range of operating frequencies of the VNA that goes from 300 KHz to 20 GHz were studied. A positioning structure was used to control the azimuth angle and the vertical axis, the movement about the azimuth angle was controlled by an Arduino one, while the vertical movement that positions the test antenna was controlled by the connected NI 9512 modules which were connected to the cRIO 9035 data acquisition system, the positioning structure used was located inside the anechoic chamber, allowing the elimination of all electromagnetic interference existing in the environment. The test antenna was connected to port two of the vector network analyzer while the pattern antenna was connected to the first port of the VNA. The separation of these antennas was greater than the far field zone, allowing the extraction of the information on the S21 transmission coefficient. The application designed in the LabView software allowed synchronized actions and automate the VNA calibration, extracting the data as the azimuth angle of the test antenna varied, generating a vector with the S21 parameters to later be able to graph the radiation pattern. of the antenna in polar and rectangular coordinates that is shown to the user through a graphical interface.