Disney is no stranger to technology. The theme parks have had very advanced systems for many years, not only in neat animatronics but also in audio systems and theme park automation. One of the really cool tools they've put out fairly recently is the MyMagic+ system or MagicBand.
Wearing the MagicBand allows you to charge meals and other purchases, gain access to attractions, pretty much anything you can think of using an RFID badge for. Here's a quick rundown of the system.
One person decided to take the MagicBand down to the bare metal and see exactly what was going on inside. Being already aware of RFID technology, they weren't too surprised to find an RFID chip and antenna. However, there was also another complete circuit with a battery and larger antenna.
At this point, one might be tempted to stop, curiosity abated. This article does not stop though. The person going by the name "AtDisneyAgain" searched out and found the FCC documentation for the short range RFID system as well as the long range system. You can find all the detailed pictures of the teardown as well as all the documentation of the MagicBand as well as the receiver domes that communicate with it on their website.
I did a teardown (more like ripapart) as well and then I found your article. The central chip they couldn't figure out has marking NRF CO 24LEDN which I think stands for custom version of NRF24LE1 for Disney ("DN") from Nordic Semiconductor. A quick look on Nordic Semiconductor site provides this information :
The nRF24LE1 integrates an nRF24L01+ 2.4GHz RF transceiver core, enhanced 16MHz 8-bit 8051 compatible CPU, 1kB + 256B RAM, 16kB embedded Flash, and a wide range of system peripherals including a hardware AES accelerator, 16MHz and 32kHz RC oscillators, ultra low power 32kHz crystal oscillator, 12-bit ADC and SPI, 2-wire and UART serial interfaces.
The nRF24LE1 is available in 3 package options ( the first one looks exactly like the chip in the band) - 4 x 4mm 24-pin QFN with 7 generic I/O pins
We made a reservation and were directed to order our food online for the "Beauty and the Beast" restaurant in the Magic Kingdom. When we arrived for our reservation, we were told to get our drinks and silverware and sit down anywhere we wanted in the three very large dining rooms, and our food would be brought to us. Within 15 minutes, our food arrived, and the waiter confirmed that the Magic Band was used to locate us.