Large umbrella space antennas are essential for communication, monitoring and observation of Earth and space objects. Despite investigations devoted to space antenna dynamics, the disturbance impulse shape effect on the root mean square error of spacecraft antenna reflecting surface has not been studied. This paper overcomes this gap describing disturbance impulse impact on root mean square err...

1.1 Brief history of antennas and their evolution The antenna is an essential part of any wireless system as it is the component providing transition between a guided wave and a free-space wave. According to the IEEE standard definitions of terms for antennas (IEEE, 1993), an antenna is defined as a means for radiating or receiving radio waves. During the period 1885-1900, some pioneers invente...

This paper introduces the FLOSS Free Libre Open Source Software [VEMSA3D], a contraction of "Visual Electromagnetic Simulator for 3D Antennas", which are geometrically modeled, either exactly or approximately, as thin wire polygonal structures; presents its GUI Graphical User Interface capabilities, in interactive mode and/or in handling suitable formed antenna data files; demonstrates the effe...

Many of the technical requirements proposed for the LWA are significantly expanded compared with the LWDA. Among the most significant changes in requirements is the wider operating band of the LWA, nominally 20 MHz to 80 MHz [1], compared with 60 MHz to 80 MHz for the LWDA. This presents new challenges in designing many of the system components including the antenna. Requirements for an LWA ant...

This paper proposes a quasi-static conformal mapping analysis to analytically evaluate the input resistance of Archimedean spiral antenna at its radiation region. The deviation from the original constructs of band theory for two-wire spiral antennas leads to the concept of common slot-line mode radiation. The per-unit-length capacitance and the characteristic impedance of the quasi-TEM fundamen...

Microstrip patch antennas are used for mobile phone applications due to their small size, low cost, ease of production etc. The MSA has proved to be an excellent radiator for many applications because of its several advantages, but it also has some disadvantages. Lower gain and narrow bandwidth are the major drawbacks of a patch antenna. In this paper, a survey on the existing solutions for the...

Since the end of 19th century, radioelectronic devices (REDs) have actively penetrated into all modern community spheres. Achievements in fields radio engineering and electronics, as well computing, information, telecommunications, other technologies, greatly contributed to this. The main elements REDs are antennas microwave devices. For example, linear (wire) basis long-distance communication ...

Monopole antennas have several advantages but for their narrow bandwidth. Broadband planar monopole antennas have all the advantages of the monopole in terms of their cost, and ease of fabrication besides, yielding very large bandwidths. For many applications large bandwidth is required. Recently, many techniques to tailor and optimize the impedance BW of these antennas have been investigated. ...

New methods are presented for increasing the bandwidth of wire antennas using impedance loading. This paper extends the seminal Wu-King theory of the internal impedance profile that produces travelling-wave only current modes on a center-fed dipole antenna. It also presents a numerical optimization methodology based on Central Force Optimization, a new deterministic multidimensional search and ...

Electromagnetic radiation and scattering are considered important topics in electrical engineering and technology, and help form the foundation of electromagnetic interference and electromagnetic compatibility. A comprehensive understanding of the radiation and scattering phenomenon will benefit the students who want to be engineers in the fields of RF circuit design, antennas and wireless comm...