rfid tag for high frequency,13.56MHz.

[sabirah]

rfid tag

hi everyone

..i have problem to design RFID tag for high frequency,13.56MHz.i don t know how to calculate the dimensions of the RFID tag.the length, width, thikcness, the spacing between each loop and the width of cooper line.i'm using FR4. the design RFID tag for antenna with small dimensions is a loop antenna.

i'm so glad if u all can help me to solve it. .

 

[karesz]

rfid tag

Hi,

you must search for "planar coils"...
Typically has a Transmitter some value at 0.5- 1 uH, the Receiver at 1.5-2uH, but the dimensions are very different depending of your envyronment...

What means "small dimensions" pls?
K.

Added after 35 minutes:

>you must search for "planar coils"...
And for spiral coils/inductances too.

Added after 33 minutes:

For small ones (measures such mm) is surly correct:
L=(14 . 10^-7)N2 and multiplyed by the product of (Router+Rinternal)2,divided by 2.14 . Router-Rinternal.
From:
S.Butteworth: Effective Resistance of Inductance Coils at Radio Frequency. ,1926, pp203-210
& ISBN 3-89649-430-9,Passeraub: An Integrated Inductive ProxySensor, pp44.

Added after 4 hours 4 minutes:

Hi sabirah,

you can find good calcution methods & RFID generell guides in "MicroID 13.56MHz RFID System Design Guide" from MicroChip.
https://ww1.microchip.com/downloads/en/DeviceDoc/21299E.pdf
Sorry I can not download some things today fro server ww1.micrchip...

I have a printed exemplar of the 125KHz version, you have in this the COIL CALCULATION formulas on pp50-66 BETTER (more detailed)as in the 13.56MHz script, but both application notes called AN 710(good the one better is exactly: AN710 microID 125KHz Design Guide _the other only simple=AN710!!)...
K.

 

[warez]

hi there..

i just want to ask a quick question, do they have a software to simulate or to calculate the dimensions of the coil antenna. I mean to confirm the value that we used is reliable?

Thanks
warez

 

[karesz]

Yes.
The firm is i.e. www.Sonnet.com...
To calculate it_you should check i.e. Microchips home side, they has two GOOD Appl Notes over RFID, for 125 KHz & 13.56MHz, I think the last is better wroten....(I checked yet, I did write it some earlyer.)
K.
To end; you have so & so to measure the developed system in detail, as antenna matching & reader distances + EMC...

 

[warez]

are you sure that www.sonnet.com is a software to clarify the dimensions of the antenna? it looks weird for me. i want to design nfc antenna circuit by using pcb boards. so i need to calculate the inductances, how many turns the coils, the spaces between them, do you have any recommendation software for that?

 

[volker_muehlhaus]

Two documents on RFID tag analysis can be found here (middle of the page):
https://www.sonnetsoftware.com/resources/

Free student version of the Sonnet EM simulator: https://www.sonnetsoftware.com/products/lite/

 

[warez]

thanks for the helps..

 

[FvM]

FastHenry www.fastfieldsolvers.com is a good tool for inductance calculation.

 

[warez]

FvM,

I guess this software for general inductance calculations. This is not for nfc antennas (RFID tags) measurements. but if you have something familiar, please advise

tq

warez

 

[breadant]

Hi,

if u r ADS user, u may find the line calculator.

actually, it is for filter design, i use it for antenna.
(but sometimes it gives me disapoint. -_-

GL