Large-capacity surface acoustic wave radio frequency tag

Abstract

The invention discloses a large-capacity surface acoustic wave radio frequency tag. Dispersion energy converters and reflectors are manufactured on piezoelectric substrate materials; sound absorption glue which is used for reducing redundant sound reflective signals coats on two end surfaces of the piezoelectric substrate materials; the piezoelectric substrate materials are in bi-pass structures; each channel is formed by one dispersion energy converter and the plurality of reflectors; an antenna is a bipolar antenna; two arms of the antenna are arranged on bilateral sides of the dispersion energy converters. The antenna converts inquiry signals sent from a reader to sound signals after receiving the inquiry signals, the sound signals reflected by the reflectors are transmitted back to the energy converters, and then the sound signals are radiated through the antenna after being converted into electrical signals. The center frequency of the dispersion energy converters is 600 MHz, the dispersion bandwidth is 250 MHz, and the dispersion time width is 0.25Mus. Each channel is provided with 10 reflectors. The large-capacity surface acoustic wave radio frequency tag can achieve far operating distance, large coding capacity and wireless and passive and the like functions and can work under severe environments such as intense radiation, high pressure and poisonous environments.

Description

technical field [0001] The invention relates to a radio frequency tag, in particular to a large-capacity surface acoustic wave radio frequency tag. Background technique [0002] Bar codes and magnetic cards are cheap and have been widely used. Bar codes have been used for supermarket product identification, hospital sample identification, airport boarding pass identification, and magnetic cards have been used for bank cards; but both tags require the reader to be in contact with the tag or Proximity can be correctly identified. In addition, manual operation is required to maintain the correct direction between the reader and the tag, and there is no obstacle between the reader and the tag, thus limiting the application in some occasions. [0003] Compared with bar codes and magnetic cards, RFID (radio frequency identification) has a longer working distance. The reader emits radio frequency signals, and the label returns a coded signal after receiving the radio frequency sign...

AI Technical Summary

Problems solved by technology

Most of the RFID market uses tags with chips. The limited range and high cost make it impossible to replace barcodes and magnetic card tags.

[0005] Chipless RFID does not contain a micro-processing chip, and relies on magnetic materials or non-semiconductor films to achieve encoding. The price is relatively low. Although the price is low, the operating distance is limited, usually only a few centimeters. use

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