RFID circularly polarized air microstrip antenna

Abstract

An RFID circularly polarized air microstrip antenna provided by the invention is characterized in that a lower-layer metal radiation patch is arranged above a metal grounding plate, and an upper-layermetal radiation patch is arranged above the lower-layer metal radiation patch; a metal pillar is fixedly installed in the center of the metal grounding plate, and the upper metal radiation patch andthe lower metal radiation patch are fixedly installed on the metal pillar through the installation holes respectively; a feed network is L-shaped and is connected with the lower radiation patch, a metal tuning sheet is arranged between the feed network and the metal grounding plate, a metal screw is arranged between the metal tuning sheet and the feed network, and a feed probe is welded at the bottom of the metal tuning sheet. The antenna has the advantages of being small in size, low in profile, large in gain, wider in 3dB axial ratio and impedance bandwidth and the like, the impedance bandwidth of the antenna can be increased, the standing-wave ratio of the antenna can be reduced, the axial ratio of the antenna can be effectively reduced, and the ideal axial ratio bandwidth can be obtained.

Description

technical field [0001] The invention relates to the technical field of antennas, in particular to an RFID circularly polarized air microstrip antenna. Background technique [0002] Radio frequency identification technology (Radio Frequency Identification, RFID) is a kind of automatic identification technology. It performs non-contact two-way data communication through radio frequency, and uses radio frequency to read and write recording media (electronic tags or radio frequency cards), so that To achieve the purpose of identifying targets and data exchange. In the RFID communication system, external hardware devices can be divided into host computer systems (including databases and data processing programs), RFID readers, RFID near / far field antennas, and electronic tags. The ring plays a key role in the stability and recognizability of the signal. [0003] At present, RFID far-field high-gain antennas generally adopt the form of dielectric interlayer microstrip patch ante...

AI Technical Summary

Problems solved by technology

Among them, due to the high cost of dielectric materials, large loss, and narrow bandwidth, the application scenarios of dielectric interlayer microstrip patch antennas are limited.

The (type) even / monopole antenna array, due to its high profile, large volume and complex structure, cannot be well adapted to the application of narrow spaces.

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