Title:
CIRCUIT FOR SHIELDING SIGNALS AND ANTI-THEFT DEVICE THEREOF
Document Type and Number:
WIPO Patent Application WO/2018/049709
Kind Code:
A1
Abstract:
A circuit for shielding signals and an anti-theft device thereof are provided. The circuit comprises a signal receiving and transmitting antenna circuit and a diode D3. Two terminals of the diode D3 are respectively connected to an input terminal and an output terminal of the signal receiving and transmitting antenna circuit. When an external illegal signal theft apparatus approaches the device, a first antenna and a second antenna receive alternating electromagnetic waves. After alternating currents in the first antenna and the second antenna pass through a diode D1 and a diode D2, the currents enter an inductor L1 and a capacitor C1 to form a resonant circuit, causing electrical resonance. When an oscillation current passes through the inductor L1, the inductor L1 generates inductance therein due to the change in direction of the current, such that the energy of electromagnetic waves goes into the antenna and are emitted to form interference signals emitted to the outside. Thus, the external illegal signal theft apparatus cannot read internal information of a chip, such as protected ID cards, bank cards, or electronic passports, reducing power consumption, generating stronger electromagnetic wave interference signals, and improving a shielding effect.
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Inventors:
TAO XIXIAN (CN)
JIANG KAI (CN)
JIANG KAI (CN)
Application Number:
PCT/CN2016/101976
Publication Date:
March 22, 2018
Filing Date:
October 13, 2016
Export Citation:
Assignee:
SHENZHEN UNION SMART CARD CO LTD (CN)
International Classes:
H04K3/00
Foreign References:
| CN104156754A | 2014-11-19 | |||
| CN204498557U | 2015-07-22 | |||
| CN205103853U | 2016-03-23 | |||
| CN204883775U | 2015-12-16 |
Attorney, Agent or Firm:
SHENZHEN TALENT PATENT SERVICE (CN)
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