Liquid-insensitive ultrahigh-frequency RFID flexible tag antenna

Abstract

The invention relates to a liquid-insensitive ultrahigh-frequency RFID flexible tag antenna. The liquid-insensitive ultrahigh-frequency RFID flexible tag antenna comprises a folding dipole arm, a multi-loop matching structure, a radio frequency identification chip and a flexible dielectric substrate, wherein the folded dipole arm and the multi-loop matching structure are formed by mechanically engraving a copper-clad flexible dielectric substrate, and a radio frequency identification chip is placed in the center; Due to the impedance adjusting effect of the multi-loop matching structure, impedance matching between the tag antenna and the radio frequency chip in the air is good, and the impedance mismatching degree is greatly reduced when the tag antenna works on the liquid surface; in addition, adjustment of the dipole arms can significantly improve the gain of the tag antenna, so the reading distance of the tag antenna can reach 8 meters and 5.6 meters in the air and on the surface ofthe liquid respectively. The RFID tag antenna is low in cost and easy to manufacture, and the problem that a traditional RFID tag antenna cannot work on the surface of liquid is solved; and meanwhile, the flexible dielectric substrate can enable the tag antenna to be conformal with any bottle body or tank body, so the tag antenna can be conveniently matched with an identified object.

Description

technical field [0001] The invention relates to the technical field of radio frequency identification, in particular to a liquid-insensitive UHF RFID flexible tag antenna. Background technique [0002] Radio Frequency Identification (RFID) technology is a technology that reads and writes memory chips in specific objects through radio signals without establishing mechanical or optical contact between the identification system and specific objects. Since the RFID system has the advantages of strong penetrability, multiple reads and writes, large data memory capacity, low cost of passive tags, small size, convenient use, high reliability and long life in the process of reading and writing, it is widely used in warehousing, logistics, etc. etc. have been widely applied. Common passive RFID frequency bands include high frequency (HF: 13.56MHz) and ultra-high frequency (UHF: 860-960MHz). Since the UHF RFID identification system has a longer reading distance, UHF is the current RF...

AI Technical Summary

Problems solved by technology

However, when there is a mismatch between the impedance of the tag antenna and the RF chip, the energy radiated by the tag antenna is too low or even the antenna itself cannot resonate at all, that is, the tag antenna cannot be read by the system.

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