High Gain Microstrip Active Antenna Utilizes as Transmitter and Receiver with Linear and Circular Polarization

In this research paper, a high gain microstrip active antenna is operating as transmitter and receiver at the same time with linear and circular polarization operations. This proposed work contains five essential parts such as high gain and broadband applications. Firstly, mainly is dealing with passive patch antennas. These selected passive antennas enjoy both high gain and broadband applications. Part two intends to convert the selected passive patch antennas into an active antenna. Part three intended to improve the performances of the proposed active integrated antennas. Part four enhancement elements (which is known as parasitic elements) are utilized in order to increase the gain of selected antennas. Part five, this proposed active integrated antennas will be converted from linear polarization (LP) into circulation polarization (CP). All the selected antennas will simulate by using models of ADS Agilent.

A Compact Wideband Active Two-Dipole HF Phased Array

The design and construction of an upgraded HF quarter-wavelength two-dipole active array with 90° difference feed was implemented in the course of a research project to perform a directional (azimuthal) investigation of interference at HF. The lack of affordable compact antennas to meet the project requirements was the incentive to develop a compact unidirectional antenna, with the maximum possible front-to-back ratio at frequencies of 20–30 MHz, where the dimensions of traditional passive antennas are enormous. By installing a low-noise very-high-input impedance amplifier in each dipole of the array, the effect of the mutual coupling between the two dipoles was reduced, improving the front-to-back (F/B) ratio over a wide frequency range. Electronic steering, easy polarization adjustment, and fast and easy deployment were the key requirements for the construction of the antenna. Therefore, a light and compact design was of the utmost importance to meet the space limitations at the monitoring site, which did not allow the deployment of a traditional HF directional antenna that employs a very long boom and elements.