Bifilar Helix Antenna Research Articles

Design, Simulation and Experiment of a Backfire Bifilar Helix Antenna for Use in S-Band Communication with a Lower Earth Orbit Satellite

Nowadays most of the Satellites are used for Radio Communication. There are so many types of Satellites, among them Low Earth Orbit type of Satellites are the most useful type of Satellites because they are used for Photograph, Telecommunication, Scientific and Military applications. In Military applications, especially for Submarine based Communication with LEO Satellites, a dual band or multi band antenna is required and the gain should be maximum in the directions of the maximum path loss. The back fire bifilar helix antenna is the most suitable for this requirement because this antenna can provide multi-band characteristics and gain by setting of the parameters like number of turns, diameter and width of the wire elements. Moreover this antenna has the advantages such as high efficiency, a convenient size at S- band and extreme simplicity. In this paper a backfire bifilar helix antenna is proposed and designed at a center frequency of S-band Satellite Communication. The designed antenna will be simulated, measured and analyzed for various characteristics like VSWR, Gain, Axial ratio and Radiation patterns at the transmitting and receiving frequencies of the S-band Satellite Communication.

Microwave Behavior of Absorbing Materials With Spirulina Coated With Pure Iron and Design a Black Body for <inline-formula> <tex-math notation="LaTeX">$W$ </tex-math> </inline-formula>-Band

Nanocomposites consisting of fine particles of spirulina coated with pure iron are able to change the dielectric permittivity and the magnetic permeability. The spirulina coated with pure iron is introduced as a kind of absorbing material, whose dielectric permittivity is $\sim 4-0.5j$ and the magnetic permeability is $\simeq 2.7-0.35j$ . The physical explanation of the fact that the spirulina structures contribute to the electromagnetic characteristics in W-band (75–110 GHz) is analyzed by the theory of the electrically small bifilar helix antenna. In addition, a black body is designed and fabricated. The emissivity of the black body is above 0.994 for both the TE and TM polarizations in the whole W-band, which meets the demanding of the remote sensing of the atmosphere.

Bifilar Helix GNSS Antenna for Unmanned Aerial Vehicle Applications

A wideband Global Navigation Satellite System (GNSS) bifilar helix antenna for unmanned aerial vehicle (UAV) applications is presented here. The antenna is designed to fit inside the vertical stabilizer of the Dakota UAV. The antenna is fabricated using a novel direct write thermal spray technology. A feeding network insert is designed incorporating a hybrid providing a balanced 200- Ω output to the antenna.

Single Feed Low Profile Omnidirectional Antenna with Slant 45$^{\circ}$ Linear Polarization

It is shown that a side-fed bifilar helix antenna with a single feed, can generate a slant 45 linearly polarized omnidirectional toroidal pattern. The antenna has a low profile and does not require a ground plane. The bifilar helix antenna provides slant 45 polarization over a solid angle of almost steradians as compared to a crossed dipole which generates a tilted 45 linearly polarized pattern only over a solid angle of steradians. The computed results are validated by experimental data.

Dual-mode compact structure comprising of side-fed bifilar and quadrifilar helix antenna

A side-fed bifilar helix antenna can be integrated with a quadrifilar helix antenna in a piggy back configuration in order to achieve a dual-mode radiating structure. The overall length of the structure is 0.44λ at the resonant frequency (1.54 GHz) of the space mode antenna and 0.39λ at the resonant frequency (1.34 GHz) of the terrestrial mode antenna. The computed results are validated by experimental data.