Unlock instant, AI-driven research and patent intelligence for your innovation.

Passive label circuit in radio frequency identification system

A radio frequency identification system and passive tag technology, applied in the field of passive tag circuits, can solve the problems of rising circuit power consumption, affecting circuit performance, and circuit failure to work normally, and achieve the effect of reducing heat generation and field strength energy

Inactive Publication Date: 2015-12-16
SHANGHAI HUAHONG INTEGRATED CIRCUIT
View PDF4 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The temperature rise will affect the performance of the circuit, especially the power consumption of the circuit will increase significantly with the temperature, so that the circuit cannot work normally

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Passive label circuit in radio frequency identification system
  • Passive label circuit in radio frequency identification system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0011] combine figure 1 As shown, in the following embodiments, the passive tag circuit in the radio frequency identification system is composed of a field strength detection circuit and a group of adjustable capacitors (ie, adjustable capacitor group).

[0012] The field strength detection circuit detects the magnitude of the currently received field strength. When the received field strength is too large, adjust the resonant capacitor group connected in parallel at both ends of the antenna to make the tag slightly deviate from the resonance point under large field strength, thereby reducing the field strength energy received by the tag and reducing the heat generation of the tag.

[0013] figure 2 It is a specific embodiment of the field strength detection circuit, which is composed of a constant current source circuit, a current discharge circuit and a current detection circuit.

[0014] The constant current source circuit extracts a fixed current from the output end of ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a passive label circuit in a radio frequency identification system. The passive label circuit comprises a field intensity detection circuit and an adjustable capacitor unit. The field intensity detection circuit detects the magnitude of a currently received field intensity, and generates and outputs a field intensity indication signal through input currents obtained from the field intensity by means of an antenna. The adjustable capacitor unit, serving as a resonant capacitor of the antenna, is in parallel connection with the ends of the antenna, and adjusts a capacitance value connected to the circuit according to the field intensity indication signal. The energy of a field intensity received by a label can be reduced, and the heating of the label can be minimized.

Description

technical field [0001] The invention relates to the field of radio frequency identification (RFID), in particular to a passive tag circuit working in a high frequency (HF) radio frequency identification system. Background technique [0002] Tags working in high-frequency radio frequency identification systems are generally passive, that is, the energy required for the tag to work is obtained by the tag antenna from the electromagnetic field sent by the reader. When the strength of the electromagnetic field sent by the card reader (referred to as "field strength") is relatively large, the energy received by the tag will exceed the energy required for its work. At this time, the excess energy will be consumed in the form of heat. This causes the temperature of the label to rise. An increase in temperature will affect the performance of the circuit, especially the power consumption of the circuit will increase significantly with the temperature, so that the circuit cannot wor...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G06K19/077
Inventor 王吉健
Owner SHANGHAI HUAHONG INTEGRATED CIRCUIT