Overview

The Arduino FDX-B Reader is a DIY ISO 11784/11785 FDX-B RFID reader designed using discrete components. This project empowers you to create hardware and software capable of reading RFID tags that are commonly implanted in animals. It exclusively supports the FDX-B protocol, noted for its prevalence in animal identification.

While this project focuses on FDX-B tags, adaptations for other protocols such as HDX and EM4100 are acknowledged, although they would require substantial redesign efforts beyond the current scope.

Project Features

• Open Source: This project is open for contribution and modification, allowing you to innovate and adapt it to your needs.
• Educational Utility: Perfect for hobbyists and engineers wanting to deepen their understanding of RFID technology, including the interactions of RFID tags and readers.
• Practical Application: Ideal for tracking and managing pets, livestock, or wildlife, enhancing your ability to monitor animal health and status.

Hardware Components

Utilizing a variety of components, the setup includes:

• Arduino compatible microcontroller [M1]
• LM358P dual op-amp [U1]
• PN2222A and PN2907A transistors [Q1, Q2]
• An RFID antenna coil
• Various capacitors and resistors

For a complete component list and shopping links, see the materials section in the repository.

Circuit Design

The project revolves around generating a 134.2 kHz carrier frequency using Arduino, which is crucial for reading FDX-B tags. By configuring timers and PWM, the Arduino outputs a square wave that drives an LC resonator shared with the antenna, enabling communication with the tags.

Tuning the LC resonator for optimal performance significantly boosts the read rate of RFID tags. The resonance frequency is tuned using a simple formula:

f = \frac{1}{2 \pi \sqrt{L \times C}}

Achieving an accurately tuned system allows for the efficient reading of tags as they modulate their data into the carrier signal, enabling enhanced identification accuracy.

Signal Processing

Once a tag is detected, the reader extracts transmitted data through a series of filters, ensuring the clarity of the signal:

• Envelope Detector using an LM358 op-amp to demodulate the received signal.
• Low Pass Filter to eliminate high-frequency noise, refining the data signal for decoding.

Amplification stages consist of two op-amps configured to ensure the output is suitable for processing by the Arduino, maintaining signal integrity throughout the decoding process.

Conclusion

Whether you are an engineer, a student, or a tech enthusiast, the Arduino FDX-B Reader project provides a robust platform for learning about RFID technology and its applications in animal identification. Dive into the repository to explore the detailed circuit designs, component lists, and ongoing discussions to further enhance this innovative project!

Related Resources

• 125 kHz RFID tag reader
• EM4100 RFID Reader Mod
• [Coil Inductance Calculator](https://www.66pacific.com/calculators/coil-inductance-calculator.