RFID (Radio Frequency Identification) wideband tag antenna

Abstract

The invention discloses an RFID (Radio Frequency Identification) wideband tag antenna. The RFID wideband tag antenna comprises a substrate as well as an IC (Integrated Circuit), a capacitance loop matching network, two feed lines and two radiation units, which are positioned on the substrate, wherein the capacitance loop matching network, the two feed lines and the two radiation units are in axially symmetrical distribution by taking the center line of the long sides of the substrate as an axis of symmetry, and the center of the capacitance loop matching network and the symmetrical center of the substrate are superimposed; the IC is welded at the symmetrical center of the substrate and used for connecting the two feed lines, and the capacitance loop matching network and the radiation units are connected by the feed lines. The bandwidth of the RFID wideband tag antenna disclosed by the invention can be effectively improved from traditional about 100M to 150M through a closed loop capacitance coupling effect formed by the capacitance loop matching network, and furthermore, the stabilization of the reading distance and the fixation of the reading position of an RFID wideband tag can be achieved.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, and in particular relates to a structure of an RFID broadband tag antenna. Background technique [0002] Radio Frequency Identification (RFID, Radio Frequency Identification) is an emerging automatic identification technology, that is, two-way data communication through wireless means, and then identify the target. A typical RFID system consists of electronic tags, readers and related software. Since the identification can be completed without physical contact between the RFID tag and the reader, the RFID system can work in harsh environments and realize the identification of multiple moving targets. [0003] In the RFID system, the reader sends a radio frequency signal of a certain frequency through the antenna. When the tag enters the area, the tag obtains the reader command from the radiation field through the tag antenna, processes it through the tag circuit, and then sends ou...

AI Technical Summary

Problems solved by technology

In the actual application of RFID, it is inevitable to deal with metal objects in quite a few applications. However, UHF bands and microwave bands are very sensitive to metals, which makes it impossible for passive tags with this working frequency Objects on metal surfaces, such as steel shelves, containers, etc., cannot work normally. Since the existing technology mostly uses microstrip dipole antennas as tag antennas, the bandwidth of microstrip dipole antennas is narrow. Once placed on metal objects, The working frequency of the tag will shift, resulting in the inconsistency between the working frequency of the tag and the reader. Usually, problems such as unstable reading distance and unfixed reading position will occur.

Images