What is a Loop Antenna?

A loop antenna is a structure in which a metal wire is wound into a certain shape, such as a circle, a square, a triangle, and the like, and two ends of a conductor are used as output ends. A multi-turn loop antenna is called a multi-turn loop (such as a spiral or overlapping winding).

The continuous development of satellite technology requires larger-diameter antennas to collect and transmit weak signals. Limited by the carrier, antennas are increasingly used in spacecraft such as communication satellites, earth observation satellites, microwave remote sensing, and deep space detectors. Spaceborne expandable antennas are generally divided into plate expandable, inflatable expandable, self-resilient expandable and mesh expandable antennas. Among them, the mesh expandable antenna has become a research focus due to the advantages of high storage ratio and low area density.

The spaceborne mesh antenna generally includes a winding rib deployment antenna, an umbrella deployment antenna, a loop deployment antenna, a frame type deployment antenna, and a module type deployment antenna. Among them, the loop expandable antenna has excellent performance in

According to the relative length of the loop antenna L and the wavelength , the loop antenna can be divided into three types: electrical large loop (L), medium loop ( / 4L), and electrical small loop (L < / 4). class. ^[2]

Loop antenna terminal

When the ring diameter increases, the current

The loop antenna is suitable for large-diameter and ultra-large-diameter antennas due to its small gathering volume, which has become the focus of research and application at home and abroad. Through the research on the expanded form of the loop antenna structure, it is found that the research goals are mainly focused on two aspects: how to increase the deployment diameter of the loop antenna by reducing the gathered volume; how to improve the profile of the loop antenna by increasing the stiffness of the deployment truss Accuracy stability.

The main technical approaches to achieve the goals of improving the loop aperture and the accuracy and stability of the profile accuracy of the loop antenna are: Astromesh series loop antenna, EGS loop antenna, Harris loop antenna, etc. are expanded / collapsed forms that change periodically repeated polygonal units; up and down Loop antennas such as two-layer deployment trusses, two layers of deployment trusses, and conical trusses are periodic repetitive ways of changing polygonal elements.

At present, many loop antennas have entered the application stage, but the market is dominated by the US Northrop Grumman's Astromesh series loop antennas and Harris's loop antennas. The development of the loop antenna structure can be used for reference and innovation of existing loop antennas to develop and apply loop antennas, promote the development of satellite payloads, and meet applications such as mobile communications, microwave remote sensing, ground observation, and deep hole detection. demand. ^[1]

Electric loop antennas are most commonly used in practice, such as antennas in radios, portable radio receiving antennas, radio navigation positioning antennas, and probe antennas of field strength meters. The electric large loop antenna is mainly used as a unit of a directional array antenna. ^[2]