Have you ever wondered how a simple tap of a bus card or access card completes a payment or verifies your identity? The answer lies in Radio Frequency Identification (RFID) technology. This technology has become an integral part of modern life, with applications ranging from retail payments to logistics tracking. However, with numerous types of RFID cards available, each operating at different frequencies and protocols, understanding how to identify and use them correctly is essential for ensuring compatibility and optimal performance.

Radio Frequency Identification (RFID) is a non-contact automatic identification technology that uses radio signals to identify specific targets and read or write data without requiring mechanical or optical contact. A complete RFID system consists of three core components:

• RFID Tag (or Card): Attached to an object, it stores the object's information.
• RFID Reader: Emits radio signals and receives responses from tags to read or write data.
• Data Processing System: Receives data from the reader, processes and stores it, and takes appropriate actions as needed.

RFID cards are categorized into three main types based on their operating frequency: Low Frequency (LF), High Frequency (HF), and Ultra-High Frequency (UHF). Each type has distinct characteristics in terms of application scenarios, transmission range, interference resistance, and data security.

• Characteristics: Operate at a low frequency with a short transmission range, typically a few centimeters. They excel in resistance to metal interference and perform well in environments with liquids or dust.
• Applications: Primarily used for short-range identification, such as animal tracking, access control systems, and parking management. Due to lower security, they are suitable for non-critical applications.
• Advantages: Low cost, mature technology, and high reliability.
• Disadvantages: Slow data transfer rates and limited storage capacity, making them unsuitable for applications requiring large data transfers.

• Characteristics: Operate at a moderate frequency with a transmission range of about 10 centimeters. They offer better data security and faster transfer rates.
• Applications: Widely used in smart cards, including public transportation cards, access cards, ID cards, e-passports, and library management. Near Field Communication (NFC) technology, commonly used in mobile payments, also falls under this category.
• Advantages: Fast read/write speeds, moderate data capacity, high security, and broad applicability.
• Disadvantages: Weak resistance to metal interference and limited transmission range.

• Characteristics: Operate at high frequencies with a long transmission range, reaching several meters or even tens of meters. They support fast read speeds and batch reading.
• Applications: Ideal for long-range, high-speed identification, such as logistics tracking, supply chain management, warehouse management, vehicle tracking, and retail inventory.
• Advantages: Long-range identification, batch reading, and high efficiency.
• Disadvantages: Weak resistance to metal interference, sensitivity to environmental factors, and higher power consumption.

Accurately identifying the frequency of an RFID card is crucial for ensuring system compatibility and efficient operation. Below are practical methods for frequency identification:

• Method: Examine the card's surface or packaging for labels indicating the frequency, such as "13.56 MHz" for HF cards.
• Advantages: Simple and requires no additional equipment.
• Disadvantages: Not all cards have clear labels, requiring alternative methods.

• Method: Use a professional RFID reader to detect the card's frequency. Readers can accurately identify the frequency and protocol of the card.
• Advantages: Accurate and reliable, providing detailed card information.
• Disadvantages: Requires purchasing specialized equipment, which can be costly.

• Method: Modern smartphones with NFC capabilities can read HF RFID cards using apps like NFC Tools. Simply place the card near the phone to display its frequency and protocol.
• Advantages: Convenient and requires no additional hardware.
• Disadvantages: Limited to HF cards; cannot detect LF or UHF cards.

Different RFID frequencies adhere to specific international standards. Two widely used protocols are:

• Frequency: High Frequency (13.56 MHz).
• Features: Short-range communication with high security, commonly used in contactless payments and identification.
• Applications: Access control systems, transit cards, and bank cards.

• Frequency: High Frequency (13.56 MHz).
• Features: Longer communication range and higher data transfer rates than ISO 14443.
• Applications: Library management, supply chain tracking, and anti-counterfeiting.

Professional readers, such as multi-port UHF RFID readers, are ideal for logistics and inventory management, offering long-range detection and batch reading.

Apps like NFC Tools can read HF card details, including frequency and protocol, and may support data writing or card emulation.

Understanding RFID card compatibility is critical to avoid system failures. For example, UHF cards are often incompatible with access control systems designed for LF or HF cards. Common issues include signal interference, card damage, reader malfunctions, and improper card placement. Solutions involve removing interference sources, checking for physical damage, restarting or replacing readers, and ensuring proper card alignment.

To ensure durability, select RFID cards made from robust materials like epoxy resin for harsh environments. Regularly inspect cards for damage and use diagnostic tools to assess performance.

Identifying RFID card types is essential for system stability and compatibility. Whether through visual inspection or specialized tools, understanding card frequencies and protocols enables efficient RFID system management. Regular maintenance and proper tool selection enhance card longevity and operational reliability.

RFID uses electromagnetic fields to identify and track tagged objects. Tags store data that RFID readers detect without direct contact, commonly used in inventory management and customer experience enhancement.

LF cards (125 kHz) are typically thicker, while HF cards (13.56 MHz) are thinner. Check labels or consult suppliers for precise information.

Yes, NFC-enabled smartphones can detect HF RFID cards (e.g., payment or transit cards) but not LF or UHF cards.

Many RFID cards are reusable, especially those with rewritable data. However, some are read-only or designed for single use (e.g., event tickets).

Test the card with a reader. Visible damage, such as cracks or bends, may indicate issues. For thorough diagnostics, use specialized tools or contact the supplier.