ISO14443 rfid receiver


I’m trying to receive a signal from a ISO14443 compliant rfid tag. I
have a
USRP N210 + gnuradio running and I issue
commands (just the anticollision loop) via a ACS ACR122U reader to a
german ID card (fake like “offical fake by Bundesdruckerei”).

As I’m a computer scientist and not that much into signal processing I
googled around and found:
About half way down the page I saw their toolchain and tried to
implement a
receiver at 12.71 MHz for one of the subcarriers.

Within the spectrum I can see that there is a signal but after
I can not see a thing in the scope plot.

Would someone be able to share a simple receiver with me so that I can
learn from that? I would really appreciate that.

Best regards

So at the moment this flowgraph is all I got:
If I tune to 13.56 MHz I can see the carrier but how can I manage to see
the ASK signal in the scope?

2013/3/30 Sebastian H. [email protected]