RFID Cards

RFID cards can be classified based on the type of operations and the frequency strength of the embedded RFID tag.

Classification of RFID cards by type of operation

Active RFID cards
These cards have a battery tag that constantly emits signals. The ability to emit and broadcast signals does not depend on the presence of an RFID reader.
Cards are mainly used to track high-value assets in high-speed environments such as payment stations. In addition, they have a longer reading range than with passive tags and are relatively more expensive.

Passive RFID cards
Unlike active tags, passive tags do not have an internal power source. They rely on electromagnetic energy emitted and transmitted by the RFID reader. As such, these tags won’t work until they get close to an RFID reader.
They are mainly used for functions such as access control, supply chain management, and smart tags. They are also relatively cheaper than active cards, so they are widely used in various industries and organizations.

Semi-passive RFID cards
Semi-passive RFID cards have an integrated circuit, antenna and battery. Although these features are almost similar to RFID cards, there is one distinguishing factor – semi-passive cards lack on-board transmitter.
As such, they have a limited reading range compared to active ones. However, the inclusion of the battery allows you to add additional functions to the card, such as real-time trackers, sensors and sound signals.

Classification of RFID cards based on the frequency wavelength of the RFID chip

RFID cards can also be classified according to the type of RFID chip used to build them. There are three main types of RFID cards in this category:

Low frequency (LF) RFID cards
These cards have LF RFID tags embedded in them (from 30 kHz to 300 kHz). They have a slower reading speed and a relatively short reading distance. However, the operation of these cards is not affected by the presence of metals and liquids. Thus, you can use them even in wet and metallic environments.

High frequency RFID cards
These cards operate in the frequency range from 3 MHz to 30 MHz. They have better memory and longer reading range than low-frequency cards. They are perfect for e.g., library management and traffic management.

Ultra-High Frequency (UHF) RFID cards
These cards operate in the range of 300 MHz and 3 GHz. They are cheaper than LF and high-frequency cards. They are mostly used for asset tracking and inventory management.

RFID card application areas
RFID cards are used in many sectors, including access control, supply chain management, and contactless payments.
RFID cards for access control
In many organizations and events, the use of RFID access cards is an effective way to maintain security. Cards are especially useful when there are restricted areas that only authorized persons can enter.
RFID cards contain small computer chips that store up to 32 kilobytes of data. This space is enough to store a unique identification code for a particular person. The data is encrypted, which prevents possible attempts at abuse. If authorized to do so, the stored data can be overwritten or modified, making them extremely flexible and cost-effective.

How RFID access cards work
RFID cards contain an RFID chip that contains data from specific individuals. This data can be transmitted via radio waves to an RFID reader.
When the cardholder gets close to a reader, the chip starts functioning by the electromagnetic wave of the reader. Then the reader will perceive the radio signals emitted by the chips. As a result, the reader records and interprets the cardholder’s data.
There are two main types of RFID access cards on the market:

RFID proximity cards. These are simple cards that allow one-way data transfer from the card to the scanner/reader. All they need is the proximity of the reader, and it is they who transmit the data.

RFID smart cards.
They offer more secure and faster access control than prox cards. They have a unique ability to communicate with RFID card readers, which allows for advanced encryption. In addition, the cards come with built-in processors that help identify the card user with a one-time encrypted code. The code expires immediately after use, making it difficult for criminals to clone the card.