RFID Tag Spoofer Based on Arduino

Overview

The purpose of the project is to spoof a simple low frequency 125kHz RFID tag with the use of an Arduino and only a few components.

Details

A single Arduino pin provides the control once tag is assembled and this is done by tuning the antenna coil to send tag code. The usual design of RFID includes a passive RFID tag that has a coil and a chip with data on it. A varying electronic field which is known as the carrier signal is created by a coil in an RFID reader. The magnetic field powers the chip on the tag, when the tag is close to the RFID reader. This will respond by tuning and detuning its own antenna as it all works on the principle of inductive coupling.

During the circuit construction, a coil that’s about 150 to 162uH needs to be created while leaving a little extra wire in case some more winding is needed for getting the antenna tuned right. It can be connected to the circuit after the coil is done while at the base of the transistor, the Arduino Pin 9 gets connected to a 10KOhm resistor.