Questions tagged [rfid]
Radio Frequency IDentification
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Extending Radiofrequency Signal [closed]
I live out in the country with a lot of fields and forests around us. I am missing my cat and this just kind of got me thinking. I know almost nothing about these kind of things and I’m struggling to ...
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How could I detect my cat from 1 meter away?
I am building an automated pet feeding system. One of the functions has to be that the system detects that the pet is near. I was thinking of using an RC-522 RFID, but the range on that is 10 cm ...
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UHF RFID antenna
When designing a UHF RFID antenna, besides matching to the chip, is there some matching to air that needs to be done (for example, to the characteristic 377 Ω)?
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Role of secondary antenna for a UHF RFID tag
I am trying to understand the role of a secondary antenna that I have seen in some UHF RFID tags. I believe it's to increase the read range of the tag.
The module seems to have an internal antenna ...
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ESP-12F module "correct" wiring for usage with MFRC522 RFID module?
I have wired an ESP-12F module as shown in the diagram below. I've seen many designs use GPIO16 for the SDA (SS) pin on the ESP-12F module, but in the datasheet GPIO15 is the CS pin.
1-Is this the ...
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Design grid of RFID readers with possible stacked tags
I want to get a grid of RFID readers in rather close proximity (cells should be around 45mm x 45mm -- could increase a bit if necessary). I also want to be able to detect up to at least 3 stacked tags ...
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How do I detect a Faraday bag? [closed]
How do I detect a Faraday bag coming into or leaving my store?
The intention of detecting Faraday bags is to be aware of customers who have the ability to walk out of the store with an RFID-tagged ...
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RFID tag sensitivity values
The datasheets of the passive UHF RFID tags mentions the read and write sensitivity values in dBm. I see that the reader transmit power is usually mentioned in watts and dBm values can be converted to ...
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RFID-based access control system
I want to make a RFID-based access control system with an ESP32 and the Arduino IDE.
I found code from electronoobs and a video; it looks nice. I have tested it, and it works with the RC552.
When ...
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RFID Antenna Simulation using MATLAB
I have designed a PCB with RFID antenna and I want to simulate this antenna. I know I need to use PCB Antenna Design APP in MATLAB for this. My MATLAB version is 2017b, this version only has Antenna ...
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RFID tag performance - single frequency vs band
I am trying to understand the RFID frequency bands but have some confusion. RFID tags operate on two different frequency bands 865 to 868 MHz (European) & 902-928 MHz. Are the RFID readers ...
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Connecting LCD I2C and RFID tag to esp 32 devkit
I want to connect LCD I2C and RFID card reader to esp32 devkit. My problem is they both have SDA pin and on esp I only see one, so how can I work on that?
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Arduino isn't seeing PN532 chip
I am having an issue with the PN532 reader:
I would like to use the module with an Arduino Uno, and read 13.56 MHz tags.
I choose the UART connection, and soldered pin, as shown here:
*EDIT, the ...
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Powering a 1mA - 100mV amplifier with the output of an MCU without directly supplying 1mA
I'm trying to design a super low power consumption tag for RFID applications. The idea is to power all the circuitry with the I/O of the microcontroller.
I am assessing two different low power ...
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3D RFID LF coil antenna - resonance
I'm designing a 3D 125 kHz RFID only-receiver (you can think about it as a field detector - the tag will not respond with classic field load modulation), which will have three separate coils in XYZ ...
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How to decide RFID tag antenna inductance?
I know how to calculate the antenna inductance of a given RFID tag antenna but how do I decide what value of antenna inductance is needed for the design?
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Limits to I2C switching multiple RFID/NFC readers with Raspberry Pi and I2C switch
I am trying to set up an assembly line scenario where an item with and RFID tag is slid across an assembly line to different stations on a table.
In the image below you can see ID tags A and B as they ...
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1 vs. 2 balun(s) on extension cable
I am quite new to SDR and RF learning and experimenting.
I am trying to build an extension cable to relay an RFID signal (125kHz) to various distances (2,5,10m). I am using 2 identical antennas at ...
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125 kHz Arduino RDM6300 read issue
I've tried to read a 125 kHz signal with an Arduino using an RDM6300 module, but it didn't work.
I tried to catch the signal with Audacity. Please find attached photo with the signal.
How can I catch ...
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RFID project using STM32F446 Nucleo board, I need to feed my board with 5 V using a powerbank, is that possible?
I'm working on an RFID project using an STM32F446 Nucleo board. I need to feed my board with 5 V using a powerbank, is that possible?
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Receiver antenna design for reading PIT tags implanted in snakes and reptiles
I am talking to a local conservation outfit trying to replace active implantable radio tags with passive PIT tags (I do not know who the manufacturer is). These active tags are really tiny glass ...
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NodeMCU RF522 connection not working
I have a NodeMCU which is connected to a RF522 sensor and a LCD display.
I did the connection as follows
D4-SDA
D5-SCK
D7-MOSI
D6-MISO
GND-GND
RST-D3
3V-3.3V
LCD-I2C is connected nodeMCU as:
GND-GND
...
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Why does my phone's RFID UID change each time I scan it on a RFID scanning system?
I am currently playing around with RFID on my Arduino UNO using RC522 module. I have followed a code tutorial from this website https://arduinogetstarted.com/tutorials/arduino-rfid-nfc and am able to ...
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mfrc522 Arduino library -> RFID ERROR: PCD_Authenticate() failed: Timeout in communication
I'm trying to do a project using RFID tags to store information to be retrieved later with another device. Kind of a storage memory.
I've bougth several tags which I can write and read with several ...
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Multiple antenna single rfid
I am using 134.2 kHz RFID reader module. My module has VCC pin (5V-12V), GND , TX(don't have RX pin, Module has one way communication) and reset pin. I need to use at least 4 RFID reader for my ...
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RF coils in UK roads tarmac
I'm not sure if this the right place to ask, but I think it's still related here.
Increasingly, I've been noticing more and more rectangular cut-throughs in the tarmac of UK roads. Usually, they are ...
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Antenna inductance calculation (RFID applications, inductive coupling)
Inductance of various antenna coils of different shapes can be estimated. Some examples are:
A circular coil with single turn.
N turn multilayer circular coil.
Spiral coil.
N turn squae loop coil.
...
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How can I read an RFID tag at the back of a phone FROM THE FRONT?
I'm discovering RFID applications and I would like to be able to read an RFID card I strapped to the back of my phone (the most convenient location for me) by just putting the phone face down on the ...
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Multiple Tags with RFID then play media from RPi
I was wondering if it is at all possible for an RFID reader to read an NFC tag, then ignore that tag, while still being available for other tags which are placed in sequence?
The project is a board ...
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How does the resonant capacitor work in an RFID antenna?
I am trying to design a custom antenna for an RFID circuit I am building.
I want to make a ~20 cm circular antenna to read a tag that passes through. I still can't have success.
Reading this http://...
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125 kHz RFID antenna and read range relation
I have designed 125 kHz RFID reader circuit with which I can read regular card type tags around 4-5 cm and key tag type around 2 cm range. You can see my current circuit and antenna information from ...
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What would be the best small signal model to the following LF RFID circuit?
I'm trying to analyse a LF RFID circuit's antenna of a TMS3705 base station using simulation. I want to estimate the frequency response and the Q factor. The intention is to do it for two different ...
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How to do a comparative analysis of electrical characteristics of two 134kHz RFID circuits?
In the figure below there are two antenna circuits, both are circuits used in RFID at 134kHz, which are external to the TMS3705 IC. Circuit number 1 is an old circuit, circuit number 2 is the circuit ...
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RFID read distance and frequency
In RFID (according to this source: https://blog.acdist.com/understanding-rfid-and-rfid-operating-ranges) there are:
Low Frequency RFID:
has the shortest read distance, about 10 centimeters between ...
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RFID Multiplexing
I'm planning on doing some project just for fun and education purposes. My project involves RFID technology. I don't have much experience on this topic, however I've been doing research on it and I ...
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Can RC522 wake up host controller from deep sleep?
I am using ESP32 with RC522 (MRFC522) module with Arduino IDE. Library used is MFRC522 installed from arduino IDE too. Examples works fine.
Is it even possible to use IRQ pin given in module to wake ...
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Can PN7150 NFC controller deactivate RF Interface?
I have used the PN7150 NFC chip from NXP in autonomous polling mode with LPCD disabled.
I can detect NFC Tag and can see NFC coil signals are changing as the NFC tag is detected.
PN7150 VDDTx current ...
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Need help troubleshooting problem with RFID antenna
I do computer support in our public library. Lately I've run into some issues with the RFID readers we use for our check out and staff stations. I'm trying to troubleshoot the problems we're having, ...
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SPI Protocol Not Working Over 3 Meters Distance [duplicate]
I am doing a project using an Arduino and a Rfid Mfrc522 module, both of them communicate using SPI protocol. The Arduino is 3 meters far away from the Rfid Mfrc522 module and I used 7 separate cables ...
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RFID reader reads only one time
I have this module: ebaylink. I have a problem: this reader reads only one time when a tag is in range. For example, when I drag a passive tag to the RFID reader, it reads one time and I want it to ...
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Related to multiple tags
I am trying to find out the following points related to multiple tags.
Whether multiple tags can have same information in them or they will always have different information.
Real life example of ...
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Demodulation and RFID Readers
I was wondering if anyone had an inclination of demodulation and packets regarding RFID chips, sensors, and tags.
When working with RF signals, and using a reader the device is capable of collecting ...
Amy
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Confused about smart card wavelengths and antennas
The tap-to-pay cards. These are also called
contactless cards, right?
And also smart cards?
The interrogator frequency is 13.56 MHz, correct?
The reply (subcarrier) frequency is .969 MHz to 3.013 MHz,...
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Is there a type of sensor that could measure how many times something has been scanned?
I'm doing a high school assignment for a project and I wanted to measure how many people are on a bus at a given time by scanning a bus card onto the reader, which hopefully there would be something ...
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How do I design the Tx and Rx path using a single antenna without using Tx/Rx switch?
I am trying to make a communication system where my module will transmit the commands and the asset tag will reply back (UHF RFID communication (868 MHz).) I will be using an antenna for far field ...
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Circuit required to clean-up an extracted On-OFF-Keying (OOK) Pulse Interval Encoded bit streams
I have a RFID reader that sends an Amplitude Modulated On-Off-Keying (OOK) Pusle Encodede bit stream to a T5577 RFID tag. I am trying to capture the reader to tag communication. To this end, I built a ...
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Calculate inductance and capacitance of a double layer antenna (RFID)
I want to design an antenna that will work with RFID NFC chip NHS3152.
The NHS3152 IC specs are:
IC capacitance at precise measurement conditions
For this particular IC, there is a demoboard.
Since I ...
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Power minimization in a battery powered NFC Reader?
I have been trying to design a Battery powered NFC Reader using Quectel SC60 module with SAM interface.
So , the problem is that in the reference design, LDO is always connected to VBAT thus draining ...
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2
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Secure Access Module (SAM) connected directly to MCU bypassing the reader IC
I have been trying to design an NFC Reader using a Quectel SC60 module with a Secure Access Module (SAM) interface.
The problem is that in the reference design, the SAM is connected directly to the ...
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Is using an over voltage rated capacitor going to work equivalently in this circuit?
Total noob at electronics, apologies if this is a daft question.
Circuit picture is here which is a RFID module, but in my case connected to an Arduino Nano rather than a USB dongle.
I broke the 10 V,...
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