The helical antenna is designed and constructed into a spiral shape using wires. These antennas are considered one of the simplest antennas and are widely used for VHF and UHF operations. Therefore, it has found applications in satellite relay and other extraterrestrial communications. The operating frequency of the helical antenna is between 300 MHz and 3 GHz. Generally, helical antennas radiate circularly polarized waves and support two operating modes, which are normal mode and axial mode.
The helical antenna is a type of antenna that can transmit and receive polarized electromagnetic signals rotating in space. Such antennas are usually used in ground stations for satellite communications. Use an unbalanced feeder, such as a coaxial cable, to connect the antenna. The center of the cable is connected to the spiral part of the antenna, and the outer sheath of the cable is connected to the reflector.
From the outside, the spiral antenna looks like a spiral is installed on a flat reflective screen. The minimum size of the antenna depends on the frequency of the low-frequency signal used. If the spiral or reflector is too small, the efficiency of the antenna will be severely reduced. In the axial part of the helical antenna, the energy of the electromagnetic wave is the largest. A helical antenna is usually composed of multiple helical parts and a reflector. You can move the entire group of antennas vertically or horizontally to track a satellite at the same time. If the satellite is not in orbit, the azimuth angle of the antenna can be adjusted by the computer to track the satellite's trajectory.
The helical antenna has different functions and benefits human being a lot. HBTE technologies offer a series of RF antennae, from the logarithmic antenna, and helical antenna to the dual-polarized Vivaldi antenna.
The various advantages of helical antennas are: they provide a simple construction. Helical antennas exhibit highly directional behaviour. It provides a wide range of working bandwidth. And the operating frequency range is very high, which can operate in VHF and UHF.
Helical antennas are used mainly in space communications. Their simplicity, high directivity, wide bandwidth, and circular polarization are parameters of space communication operations. Generally, telemetry data in space communication is transmitted through helical antennas. In addition, by placing single or array helical antennas on the surface, the propagation of ionospheric waves can be achieved. This allows VHF signals to be sent and received. Therefore, satellites and space probes use helical antennas for propagation. The helical antenna configured in axial mode can easily receive signals of any polarization. Because the end-fire helical antenna provides circularly polarized waves over a wider bandwidth, helical antennas with wider sides are widely used.