869  RFID Fundamentals and Standards

869.1 Radio Frequency Identification (RFID)

This section provides a comprehensive guide to RFID technology for IoT applications. The content has been organized into focused chapters for easier learning and reference.

869.2 Chapter Overview

RFID (Radio Frequency Identification) enables automatic identification without line-of-sight or power on the tag, using radio waves to read unique IDs from centimeters to hundreds of meters away. This technology is foundational for IoT applications in inventory management, access control, supply chain logistics, and asset tracking.

NoteKey Takeaway

In one sentence: RFID enables automatic identification without line-of-sight or power on the tag, using radio waves to read unique IDs from centimeters to hundreds of meters away.

Remember this rule: Use passive tags for cost-sensitive high-volume tracking (under $0.10 each), active tags when you need range over 10 meters or real-time location, and choose your frequency band based on read range needs (LF for contact, HF for 1m, UHF for 12m+).

869.3 RFID Chapter Series

869.3.1 1. RFID Introduction and Fundamentals

Difficulty: Beginner | Reading time: ~15 minutes

Start here if you’re new to RFID. This chapter covers:

  • What RFID is and how it works
  • The “Marco Polo” analogy for reader-tag communication
  • RFID vs. barcodes vs. NFC comparison
  • Historical context and evolution
  • Basic operating principles

869.3.2 2. RFID Tag Types and Components

Difficulty: Intermediate | Reading time: ~12 minutes

Understanding tag types is essential for selecting the right RFID solution:

  • Passive tags: Battery-free, powered by reader, lowest cost
  • Semi-passive tags: Battery for sensors, RF for communication
  • Active tags: Full battery power, longest range
  • RFID system architecture (tags, readers, middleware)
  • Power consumption and battery life calculations

869.3.3 3. RFID Frequency Bands

Difficulty: Intermediate | Reading time: ~15 minutes

Different frequencies provide different capabilities:

  • LF (125 kHz): Short range, excellent metal/water tolerance
  • HF (13.56 MHz): NFC compatible, payments, library systems
  • UHF (860-960 MHz): Long range, supply chain, retail
  • Microwave (2.45 GHz): Vehicle tracking, active tags
  • Interactive frequency comparison tool
  • Environmental interference (metal, liquids)

869.3.4 4. RFID Standards and Protocols

Difficulty: Intermediate | Reading time: ~12 minutes

Standards ensure interoperability across vendors and applications:

  • ISO 14443: HF proximity cards (payments, access)
  • ISO 15693: HF vicinity cards (library, item tracking)
  • EPC Gen2: UHF supply chain standard
  • Anti-collision protocols (Q-algorithm)
  • NFC Forum standards

869.3.5 5. RFID Design and Deployment

Difficulty: Intermediate | Reading time: ~18 minutes

Practical guidance for real-world RFID systems:

  • Decision framework for frequency and tag selection
  • Common deployment pitfalls and how to avoid them
  • Worked examples: retail apparel tracking, warehouse scanning
  • Friis equation for range calculation
  • Anti-collision optimization
  • Multi-technology hospital example

869.4 Quick Reference

869.4.1 Frequency Selection Guide

Need Frequency Why
Pet microchips, metal environments LF (125 kHz) Penetrates tissue/metal
NFC payments, smartphones HF (13.56 MHz) NFC standard
Retail inventory, supply chain UHF (860-960 MHz) Long range, fast reads
Vehicle tracking, RTLS Active UHF or 2.45 GHz Very long range

869.4.2 Tag Type Selection Guide

Need Tag Type Why
Low cost, no maintenance Passive No battery, unlimited life
Temperature/sensor logging Semi-passive Battery for sensors
100+ meter range, RTLS Active Battery-powered transmitter

869.6 Learning Path

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flowchart LR
    A["RFID Introduction"] --> B["Tag Types"]
    B --> C["Frequency Bands"]
    C --> D["Standards & Protocols"]
    D --> E["Design & Deployment"]
    E --> F["Hands-on Applications"]

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Figure 869.1: Recommended learning path through RFID chapters

869.7 What’s Next

Start with RFID Introduction and Fundamentals if you’re new to RFID, or jump directly to a specific topic using the chapter links above.