RF card overview.
RF card is composed of 330BIT chip, induction antenna, packaged in a standard PVC card, the chip and antenna without any exposed part. Is a new technology developed in the world in recent years, it successfully combines the radio frequency identification technology and T5577 card technology, ending the passive (no power in the card) and no contact this problem, is a major breakthrough in the field of electronic devices. Card in a certain distance range (usually 5-10mm) close to the read-write surface, through the transmission of radio waves to complete the data read-write operation.
Through different ways, we can divide the RF card into the following categories.
1. According to the power supply method is divided into active card and passive card.
2, According to the carrier frequency is divided into low frequency RF card
3, according to the different modulation mode can be divided into active and passive
4, according to the role of distance can be divided into dense coupling card
5, according to the chip classification as read-only card.
Here we come to understand, what is the active card and passive card?
Active refers to the card has a battery to provide power, its action distance is long, but the life is limited, larger, high cost, and not suitable for work in harsh environments; passive card without batteries, it uses beam power technology to convert the received RF energy into DC power for the card circuit power, its action distance is relatively short active card, but the life is long and the working environment requirements are not high.
What is low frequency card?
Medium frequency RF card and high frequency RF card. Low frequency RF card mainly has two kinds of 125kHz and 134.2kHz, medium frequency RF card frequency mainly for 13.56MHz, high frequency RF card mainly for 433MHz, 915MHz, 2.45GHz, 5.8GHz, etc.. Low frequency systems are mainly used for short distance and low cost applications
Active and passive type?
The active type RF card uses its own RF energy to actively send data to the reader; the passive type RF card uses the modulated scattering method to transmit data, it must use the readers carrier wave to modulate its own signal, this kind of technology is suitable for use in the access control or traffic application, because the reader can ensure that only activates the RF card within a certain range. In the case of the obstacle, with the modulation scattering method, the energy of the reader must come and go through the obstacle twice. And the active way the radio frequency card transmits the signal only passes through the obstacle once, therefore the active way work the radio frequency card mainly uses in the application which has the obstacle, the distance is farther (may reach 30 meters).
Close coupling card?
Close coupled card (the action distance is less than 15 cm), sparse coupled card (the action distance is about 1 m) and long distance card (the action distance is from 1 m to 10 m, or even more).
Application scope: access control attendance, consumption, membership card management, sauna, entertainment, club, induction smart door lock, enterprise one-card system, access control, channel system, etc.