How RFID Works

We will demonstrate using Prox from HID Global, a common access badge system
The reader generates a 125 kHz sine wave electromagnetic (EM) field
An antenna in the card is brought into that field
A bit of the power in that field is “tapped” to power the card
The card’s antenna is tuned and dampened to create the HID message
The strength of the field in the reader’s antenna changes with the dampening of the card