Mifare Antenna Design

[Ufuk Varl?k]

Posted on January 31, 2017 at 07:53

In my design;

pcb total layer  : 4

Antenna layer  : 2nd

The components to be assembled are only in the fourth layer.

Real and theoric results are don't match.

I want increase inductance value of antenna, but on the contrary, the value is decreasing too.

What is reason ? thank you for yours help.

ANTENNA 1 RESULTS:

-THEORY INDUCTANCE VALUE  : 1.84 uH

-REAL INDUCTANCE VALUE        : 3.3 uH

ANTENNA 2 RESULTS: 

-THEORY INDUCTANCE VALUE  : 6.62 uH

-REAL INDUCTANCE VALUE        : 0.7 uH

#antenna-design

[Henry Crane]

Posted on January 31, 2017 at 16:25

Hello Ufuk,

we do confirm the theoretical values for design 1 and 2 using an RF simulation software. Based on our experience, we are confident that antenna a inductance measurements should be very close.

Two possible explanation of a difference between simulation and prototype are, first short cuts between turns of the loops, second an implemantation issue of the antenna on the PCB: if for any reason some area of copper covers the loop antenna, magnetic flux is blocked resulting in a measured inductance much lower than expected.

If you are planning to use an ST product (Mifare is not an STMicroelectronics product brand), we could go further into the analysis of your pcb layout.

best regards,

NFC Hardware support 2

[Ufuk Varl?k]

Posted on February 01, 2017 at 07:48

Thank you for yours explanation. I want to improve the current antenna. Antennas are in the same region both pcb's. Also I've designed another pcb using M24LRE. I ordered the sample and I will try it.