An RFID card is a credit card-sized device that uses embedded radio frequency identification (RFID) technology to wirelessly transmit data. Unlike traditional cards with magnetic stripes, RFID cards contain a microchip and antenna that communicate with readers via electromagnetic fields, enabling touchless authentication, payments, and secure access.
1. Core Components & How They Work
🧩 Inside Your RFID Card:
Microchip: Stores encrypted data (e.g., user ID, access permissions).
Antenna Coil: Harvests power from a reader’s radio waves (no battery needed).
Substrate: Layered plastic (PVC/ABS) protecting components from bending or damage.
🔄 Communication Flow:
Energy Transfer: Card enters reader’s electromagnetic field (typically 2–10cm range).
Data Activation: Reader’s radio waves power the microchip.
Secure Transmission: Encrypted data transmitted at 13.56 MHz (HF band).
💡 Key fact: Passive RFID cards never require charging – all energy comes from the reader.
2. Types of RFID Cards
Type
Frequency
Primary Use Case
Low Frequency (LF)
125 kHz
Animal tracking, basic access
High Frequency (HF)
13.56 MHz
Contactless payments, secure access
Ultra-High Frequency (UHF)
860–960 MHz
Warehouse inventory tools
Note: Most “RFID cards” refer to HF systems (ISO 14443/15693 standards) used in security and finance.
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