Ultra-wideband antenna for life detection radar

Abstract

The invention discloses an ultra-wideband antenna for a life detection radar. A metal shielding cavity is a rectangular low-reflection cavity with a front opening. An insulated medium plate is fixed at the front opening of the metal shielding cavity. Two semi-elliptic metal radiation arms are symmetrically printed on the front surface of the insulated medium plate. An interval is reserved between the semi-elliptic metal radiation arms. The two semi-elliptic metal radiation arms, adjacent to the interval, are respectively provided with an input port as the respective feed end thereof. One end of a metal strip is connected with the semi-elliptic metal radiation arms through a loading resistor, and the other end of the metal strip is electrically connected with the metal shielding cavity. The balanced output end of an impedance transformer is respectively connected with the input ports of the two semi-elliptic metal radiation arms. The unbalanced input end of the impedance transformer is connected with a coaxial connector. The other end of the coaxial connector is connected with the transmitter and the receiver of a life detection radar system. The ultra-wideband antenna is excellent in wide band characteristics and time-domain radiation characteristics. Meanwhile, the ultra-wideband antenna is compact in structure, and simple in feed mode.

Description

technical field [0001] The invention belongs to the technical field of ultra-wideband radar antennas, and in particular relates to an ultra-wideband antenna for life detection radars. Background technique [0002] In recent years, various major natural disasters and man-made accidents at home and abroad have occurred from time to time, causing a large number of casualties. Especially in densely populated cities with densely populated high-rise buildings and criss-crossing pipelines and lines, how to effectively carry out life-saving detection and positioning after disasters and improve rescue efficiency is a key issue. As a non-contact real-time imaging radar system, life detection radar can penetrate obstacles such as reinforced concrete brick walls, asphalt layers, debris flows and snow caused by avalanches for detection and perspective imaging, so it has attracted widespread attention from all walks of life. [0003] As a component for radiating and receiving electromagn...

AI Technical Summary

Problems solved by technology

Although the butterfly antenna has the advantages of wide frequency bandwidth, good radiation characteristics, simple fabrication and low cost, the input impedance of the butterfly antenna designed with a rectangular shielding cavity and resistance loading is usually around 200Ω, which is very difficult for life detection operating in the high frequency band. The impedance matching between the radar ultra-wideband butterfly antenna and the transmitter is relatively difficult, and its volume size is not conducive to system integration. The bandwidth and impedance transformation ratio have become the difficulty of the entire structural design. Therefore, it is necessary to design a planar dipole Antenna characteristics, and an antenna with relatively low input impedance and small lateral size becomes a reasonable choice

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