Broadband radio frequency identification reader-writer antenna with wide circularly polarized wave beam

Abstract

The invention discloses a broadband radio frequency identification reader-writer antenna with a wide circularly polarized beam. The antenna comprises triangular defect radiation patches, a circular coupling patch, a grounding probe, a feed probe, a feed network, a dielectric plate, a metal floor, a coaxial connector and a short-circuit pin. According to the structure, the cross-shaped gap betweenthe triangular defect radiation patches is used for radiation to broaden the circularly polarized beam width of the antenna; the grounding probe effectively reduces the sizes of the triangular defectradiation patches; the impedance matching performance of the antenna is improved by the gap capacitance between the triangular defect radiation patches and the circular coupling patch; the introduction of the air layer improves the bandwidth of the antenna; the feed network based on the hybrid ring and the TRD coupler eliminates the mutual coupling influence between the triangular defect radiationpatches, and achieves good circular polarization performance.

Description

technical field [0001] The invention relates to the technical field of antennas, in particular to a broadband radio frequency identification reader antenna with a circularly polarized beam width. Background technique [0002] Radio Frequency Identification (RFID) is a non-contact automatic identification technology through radio frequency signals. With the market demand and the continuous development of UHF RFID technology, RFID products are widely used in logistics management, intelligent tracking, smart cards, animal tags, electronic toll collection and store security and other fields. Among the various antennas that can be used for UHF RFID system readers, the patch antenna has been more researched and applied due to its advantages of low cost, small size, light weight, easy processing, and flexible feeding structure. [0003] The antenna is a bridge to realize the information transmission between the radio frequency tag and the reader. The antenna of the RFID reader is ...

AI Technical Summary

Problems solved by technology

However, the existing circularly polarized reader antennas have narrow circularly polarized beams, and can only identify tags within a small beam range near the maximum radiation direction, which is not suitable for large-scale identification applications.

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