Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

UHF reader demodulation circuit

A technology of demodulation circuit and reader-writer, which is applied in the direction of instrument, diode modulation transformation, computer components, etc., can solve the problem of low mixing voltage gain of demodulation circuit of uhf reader-writer, so as to improve the receiving sensitivity and solve the problem of The effect of low gain

Inactive Publication Date: 2011-12-14
WUHAN WINNINGCHINA MICROSYST TECH
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to solve the problem that the demodulation circuit mixing voltage gain of uhf reader is low

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
  • UHF reader demodulation circuit
  • UHF reader demodulation circuit
  • UHF reader demodulation circuit

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0012] The present invention will be described in detail below with reference to the accompanying drawings.

[0013] like figure 2 As shown, the present invention includes a 50-ohm microstrip line, two diode mixing circuits and two LC low-pass filters. The radio frequency signal will have a phase shift through the microstrip line, and the phase shift is determined by designing the length of the microstrip line. In the present invention, the impedance of the microstrip line is 50Ω, the input carrier signal and the ASK signal pass through the microstrip line to generate a phase shift of π / 2, and then go through two diode mixing circuits for frequency mixing, and finally pass through two LC low The carrier signal is filtered out by a pass filter and then output to the differential amplifier.

[0014] image 3 This is a circuit diagram of an embodiment of the passive demodulation circuit of the uhf reader / writer of the present invention. In this embodiment, the voltage doubling...

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 present invention relates to a uhf reader-writer, in particular to a demodulation circuit of a uhf reader-writer, including a 50-ohm microstrip phase shift device, two diode mixing circuits and two LC low-pass filters, wherein the 50-ohm microstrip phase The shifting device is used to realize the phase shift of π / 2 for the input carrier signal and ASK signal respectively; the two-way diode mixing circuit is a voltage doubler circuit, which is used to shift the carrier signal after being phase-shifted by the 50-ohm microstrip line phase shifting device Mix with the ASK signal; two LC low-pass filters are used to filter the carrier signal from the mixed signal and output it to the differential amplifier. The present invention adopts a simple Schottky diode as a frequency mixing element, and designs the frequency mixing circuit as a voltage doubling form to improve receiving sensitivity, simply realizes ASK demodulation, and solves the problem of low passive frequency mixing voltage gain .

Description

technical field [0001] The invention relates to a uhf reader-writer, in particular to a demodulation circuit of the uhf reader-writer. Background technique [0002] Radio frequency identification (RFID) technology is a non-contact automatic identification technology. Or actively send a signal of a certain frequency; after the reader reads and decodes the information, it is sent to the central information system for related data processing. [0003] The RFID system generally consists of three parts, namely the electronic tag, the reader and the antenna. The space coupling of radio frequency signals is realized between the electronic tag and the reader, and in the coupling channel, energy transmission and data exchange are realized according to the timing relationship. When the system is working, the reader sends out a microwave query energy signal. After the electronic tag receives the microwave query energy signal, it rectifies a part of the microwave query energy signal i...

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 Patents(China)
IPC IPC(8): G06K17/00H03D7/02
Inventor 刘胜武长荣江金元杨春华杨国民范旺生
Owner WUHAN WINNINGCHINA MICROSYST TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com