V.E. Lyubchenko, S.A. Telegin, E.O. Yunevich

Active microstrip antennas also known as integrated antennas (IA) are very interesting for low power microwave applications because of their small size and capability to couple them into multi-element arrays for power combining. The goal of this study was to evaluate log-periodic microstrip antenna-s high frequency parameters and its radiation pattern. 3D-Tranmission Line Matrix (3D-TLM) method is used to perform the modeling experiments. Electric power density distribution in the antenna plane was calculated to investigate the aspects of the mutual and external synchronization. Antennas developed to work at the main frequency of 10GHz are considered in the article. Antenna radiation efficiency was investigated in the frequency range from 7.5GHz to 22.5GHz for the different dielectric thickness. Patch antenna and dipole antenna developed to work at the main frequency of 10GHz were modeled to compare the properties with the ones of the log-periodic antenna. During the computer modeling the essential advantages of the log-periodic antennas compared to the other considered antenna types are determined. They are wider frequency band and weak dependence of the resonant frequency on the dielectric thickness. Specific features of the log-periodic antenna electromagnetic field radiation in the near field zone to be taken into account during the antenna array development were determined.