Diseño e implementación de una antena plana con control de fase utilizando la matriz de Butler para aplicaciones radar de corto alcance.

Abstract

Applying the microstrip technology and the multiple input, multiple output (MIMO) technique for beamforming systems, the design and implementation of a phase-controlled flat antenna using the Butler matrix for short-range radar application was developed. The 4x4 Butler matrix was designed, with the configuration and structuring of its elements (hybrid, phase switch and cruiser) in order to obtain the proper operation for the required application; In addition, an array of four microstrip patch antennas, resonant at the 3 GHz frequency corresponding to the S band for radar systems, it was coupled with the Butler matrix to control the phase depending on the excited ports. In the construction, four branch-line hybrid switches of two modified sections were used which allow a 90 ° phase offset, two 45 ° phase switches and a cruiser that supports the crossing of two signals, it maintains a high isolation and does not affect the electromagnetic properties of the signals. It was possible to obtain a phase control by changing the configuration of the ports, demonstrating it with the results in the simulation and the laboratory tests. Once the radiation angles are determined for the different configurations, it is concluded that, it is applicable to radar systems of short reach, because the radiation lobe can be directed in different zones with the excitation of the ports of entry without the necessity of mechanical structures that perform antenna routing. In the case of requiring a more precise control with greater number of radiation lobes, it is recommended to use a Butler matrix with more ports.