RFID antenna lengthening/ reading form further distance

Other Hardware General Electronics
1

Hi,

I have the MFRC522 (MiFare) 13.5GHz RFID reader. I want to embed the RFID itself in something that will constrict it's ariel size. This of course will stop it working at 13.5MHz, unless I am mistaken.

Is there a way I can increase the range of the reader?

I realise this isn't exactly arduino electronics and also very specific so I hope it is in the correct section. I couldn't find an RFID forum on the net!

Thank you.

2

sonnyyu:
Xbee range problem - Networking, Protocols, and Devices - Arduino Forum

Wireless extender vs. router - Networking, Protocols, and Devices - Arduino Forum

  • Every 6 dBm receiver sensitivity gain will be double the distance.
  • Every 6 dBi antenna gain will be double the distance
  • Every 6 dBm Transmitter power gain will be double the distance.
  • Base on Friis Transmission Equation, for sub Ghz chipset, if we select 300 Mhz v.s 900 Mhz band, the distance will be 3 times more. same thing if we select 300 Mhz v.s. 2400 Mhz, the distance will be 8 times more.

Since MiFare is passive RFID, It is powered by reader. The card receiver sensitivity gain and card transmitter power gain and card antenna gain all get reduced. You need to replace FCC certified high power, high receiver sensitivity gain reader ( very pricey if you are lucky to find one).

3

Oh, I saw this in another topic. Can I not just solder an extra antenna copper wire onto the RFID reader (it seems to have tiny points for it at the top see pic)

4

Oh, I saw this in another topic. Can I not just solder an extra antenna copper wire onto the RFID reader (it seems to have tiny points for it at the top see pic)

No.

Identification - Products | FEIG ELECTRONIC might have what you need, but could cost a lot. with ID-1 size card (Credsit Card size) go up 1 m?

5

es101:
Oh, I saw this in another topic. Can I not just solder an extra antenna copper wire onto the RFID reader (it seems to have tiny points for it at the top see pic)

Those tiny holes are "vias". They connect the trace on one side of the PCB to a trace on the other side (or in another layer) of the PCB.

Generally, changing the length, or shape, of an antenna will change it's frequency. It's like (it is) adding more turns of wire to an inductor. Unless you do the math & KNOW what the outcome will be, especially at high frequencies, I wouldn't do it.

6

OK thanks everyone.

Looks like i'll have to place my RFID in the handle rather then the tip of the wand. A shame but it's a late stage in the present for me and I don't have time to order (and then code) a different MHz RFID reader (which allows for a smaller antenna).

:slight_smile: