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Uhf passive rfid tag and uhf rfid systems

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Newbie level 4
Dec 21, 2012
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i am new comer in uhf rfid. i am working development and doing a new project in UHF RFID. i want my passive uhf rfid tag can be read in some gallon of full water. example: there are nine gallons with tags. ninegallons are put such as square. how manner rfid tag which is located in center can be read?

1. Allien Tag tipe 9654
2. Fixed Reder long range ( 5 m )
3. 3 antena reader 8 dbi

what i must change my specification? or, any system can improve?

can somebody help me about this problem?
thank you very much

It is hard to understand your question. Try to rephrase it.


Okay, I will explain detail.
Now, I am doing a project in UHF RFID. In my project, I will put tag RFID on outside gallons as identification of gallons. My RFID reader must detect tag with this condition. I could detect 1 filled gallons by using 1 reader and 3 antena reader. I feel difficult if I must detect 9 gallons which arranged in square form. I need help what i do to finish this project? Thanks.

I am not an RFID expert, but have used RFID technology in a hobby project. But I still don't understand what your specific problem is.

A "gallon" is a bottle filled with a gallon of water I assume?
And I understand that you have been able to detect one of the tags, but you have difficulty reading more than one. So what happens when you try to read more than one?

Yes. Gallon is a big bottle filled with full water.

I can detect 1 gallon, but I can't detect 9 gallon for a while.
The 9 gallons are put such as square form.
And I want to detect 9 gallons for a while.

For information, My RFID specification can detect tag which located non metal and water until 5 metres
For detecting gallons, My RFID system just detect gallons until 30 cm.

Maybe, You have solution for my problems and I say thank you very much before.

I am still not sure if I understand the problem here.

You say that your RFID reader is suppose to work up to 5 metres, but it only works up to 30 cm.
If that is the problem, then you should ask the manufacturer of the RFID reader. Maybe you are using it wrong?

But maybe I misunderstand your problem?

My RFID Reader only works up to 30 cm if tag is put on gallons.
If tag which is put on other thing (non metal and water) can detected by My reader ( 5 metres )
Still confuse on my problem, sir?

Aha, I think I understand.
What kind of material is the bottles made from?

Ok, I always thought a gallon was a unit of measurement. But yeah, I've seen such bottles.

I am sure that you are aware that electromagnetic waves cannot travel through the water. So I am assuming that you have placed the RF tags facing the reader.
My guess would be that the water in the gallons affect the RF properties of the tags. And if that is the problem, the only solution I see is to find a placement for the tags where their RF signal is not disturbed through trial and error.

Sorry I can't be of more help.

Ok... Thanks...

The Placement of tag is random. We can't place tag facing the reader, sir.

Maybe, Is there power amplifier for The RFID reader to strengthen the Power of Reader?

I'm confused to expand read range on this condition.

Maybe, I have to change the RFID Antenna Reader?
Thanks sir..

If tag placement is random, then the only way to extend read range is to get a better antenna or use an amplifier, just as you have figured out.
Unfortunately, I don't know about any specific amplifiers or antennas for this purpose.

Maybe someone else on the forum has got any ideas?

Oh thanks...

I want to ask some questions for you..

Do you know suppliers for selling UHF RFID active tag, Handheld reader, and Antenna 12 dbi?

Maybe, I want to improve increasing Gain of Antenna or Power amplifier for RFID..

I am confused about power amplifier for RFID...

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