Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [rfid]

Radio Frequency IDentification

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Why does low frequency RFID have a short read range?

If I want to get the wavelength of a radio wave, I must divide the speed of light by the frequency? So having a 125 kHz RFID means an estimated 2km wavelength? If its wavelength is 2km long, why does this low frequency RFID have a short read…
Black
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Best RFID Technology for long range detection?

I am considering building an RFID reader system that can monitor runners times in a foot race. I have read that there are three different types of RFID systems. LF, HF, and UHF. Which one would be best for this application? Has anyone had success…
PICyourBrain
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Is there an electronics reason why implantable RFID capsules are made of glass?

I am curious why implantable RFID capsules are made of glass because they create a huge risk of breaking under the skin causing some serious trouble. I would guess a silver/titanium encasing will be better, and, if I'm not wrong, those metals are…
Nicu Surdu
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Is RFID the right solution

I'm an industrial designer with limited knowledge of electronics and was looking for some help. I am in the process of developing a dementia care product. The idea is to manage the access residents have to each others rooms, currently they can…
Tim
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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 before traffic lights, and located in pairs, about…
zmechanic
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Construct RFID tag to turn on/off?

I am a very novice chiphacker and am asking for ideas on how I might implement something like this. I am about to start an RFID project, which is the easy part. RFID readers are cheap, arduinos are cheap, and RFID tags are cheap. But I want the…
rascher
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DIY 130kHz RFID antenna design for reading tags in large area

I need to construct an antenna for a reader that will pick up a 134.2 kHz RFID tag. The antenna will need to be in "tunnel/culvert" under a road. The tunnel is 2 metres wide, so antenna needs to be lie across that distance. The animals carrying…
Joan
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Passive RFID Tag: Unique Identifiers

I'm a bit confused on the uniqueness of each passive RFID tag.. are they unique globally? Meaning, every RFID manufacturer (no matter if based in USA, China or India) never creates a tag with the same unique id? So if I buy a batch of China…
Level1Coder
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use RFID remotely

From the answers to this question it's clear that RFID is passive and (therefore) doesn't work in the far field. I was wondering if you couldn't use it remotely if you make an actual transmitter of the tag, sending a 125kHz carrier AM modulated with…
Federico Russo
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UHF RFID Read Ranges

I'm experimenting with UHF RFID. I have a setup that's working but my read range is only 1 - 2 feet. This is the equipment I'm using, it's all quite cheap, I don't mind spending more to increase the read range but I'm not sure which components would…
Bruce
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How to design 125Khz Antenna for 1 meter RFID reader

Firstly, I'm not from electronics background so my knowledge is limited in this area. Target System - I am looking to build/ extend the range of 125khz RFID reader upto 1 meter (~ 3ft) to be captured while walking through a gate detector (kind of…
shafir
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Tuning ID-3LA RFID antenna using oscilloscope

I've got an ID-3LA chip wired up to an arduino and an antenna I wound myself with 30 AWG magnet wire. It works, but I've read that I should be able to tune the antenna by connecting it to an oscilloscope, and then gradually adding or removing turns…
Jon Garvin
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Seeking cheap RFID reader / writer

What I do not want is one of those RFID readers which attaches to serial or USB port and writes its input to stdin. I am looking for cheap & nasty RFID reader which I can query over serial or USB; a bonus is if it is also an RFID writer but doesn't…
Mawg says reinstate Monica
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RFID system for insect tracking - range of reading

I am planning on conducting an insect-tracking experiment in the field. We are going to have square enclosures (15m x 15m), where our insects can move around freely, but will not leave the enclosure. We want to track each individual (around 50…
user33939
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Why do most RFiD tags use hexadecimal numbers?

RFID tags store one 24-digit hexadecimal number. Why use a single 24-digit hexadecimal number?
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