NFC access control card reader and NFC introduction

NFC near-field communication technology is evolved from the integration of non-contact radio frequency identification (RFID) and interconnection technologies. It combines inductive card readers, inductive cards, and point-to-point functions on a single chip, and can be compatible with Devices that are identified and data exchanged. The operating frequency is 13.56MHz, but users who use this mobile phone payment scheme must replace a special mobile phone. This technology is currently widely used in Japan and South Korea. Mobile phone users can travel all over the country with mobile phones equipped with payment functions: their mobile phones can be used for airport boarding verification, building access keys, traffic cards, credit cards, payment cards, RFID cards, etc.

Operating mode

Card emulation: This mode is actually equivalent to an IC card using RFID technology. It can replace a large number of IC cards (including credit cards) in shopping malls, bus cards, access control, bus tickets, tickets, and so on. In this way, there is a great advantage, that is, the card is powered by the RF domain of the contactless card reader, and it can work even if the host device (such as a mobile phone) is out of power.

Peer-to-peer mode (P2P mode): This mode is similar to infrared, which can be used for data exchange, but the transmission distance is shorter, the transmission creation speed is faster, the transmission speed is also faster, and the power consumption is low (Bluetooth is also similar). Linking two NFC-enabled devices can realize point-to-point data transmission, such as downloading music, exchanging pictures, or synchronizing device address books. Therefore, through NFC, multiple devices such as digital cameras, PDAs, computers, and mobile phones can exchange data or services.

Technical Features

Like RFID, NFC information is also transmitted through electromagnetic induction coupling in the radio frequency part of the spectrum, but there is still a big difference between the two. First, NFC is a wireless connection technology that provides easy, secure, and fast communication, and its transmission range is smaller than that of RFID. Second, NFC is compatible with existing contactless smart card technology and has become a formal standard supported by more and more major manufacturers. Thirdly, NFC is also a short-range connection protocol that provides easy, safe, rapid, and automatic communication between various devices. Compared with other connection methods in the wireless world, NFC is a close-range and private communication method.

NFC, infrared, and Bluetooth are all non-contact transmission methods. They have different technical characteristics and can be used for various purposes. There is no difference between the advantages and disadvantages of the technology itself.

The NFC mobile phone has a built-in NFC chip, which adds the function of two-way data transmission compared to the original RFID which was only used as a label. This progress makes it more suitable for electronic currency payment; especially what RFID cannot achieve, mutual authentication and dynamic encryption and One-time keys (OTP) can be implemented on NFC. NFC technology supports a variety of applications, including mobile payment and transactions, peer-to-peer communication, and information access on the move. Through NFC mobile phones, people can connect with the entertainment services and transactions they want at any place, any time, and through any device, so as to complete payment, obtain poster information, etc. NFC devices can be used as contactless smart cards, smart card reader terminals, and device-to-device data transmission links. Their applications can be divided into the following four basic types: for payment and ticket purchase, for electronic tickets, For smart media, and for exchanging and transmitting data.

Principle information

In passive mode, the device that initiates NFC communication, also known as the NFC initiating device (master device), provides a radio frequency field (RF field) throughout the communication process. It can choose one of the transmission speeds of 106kbps, 212kbps, or 424kbps to send data to another device. Another device, called an NFC target device (slave device), does not have to generate an RF field, but uses load modulation (load modulation) technology, that is, it can transmit data back to the originating device at the same speed. This communication mechanism is compatible with contactless smart cards based on ISO14443A, MIFARE, and FeliCa, therefore, in passive mode, an NFC initiator can detect and establish contact with a contactless smart card or NFC target device with the same connection and initialization process

The difference between NFC and RFID

First, NFC integrates a contactless card reader, contactless card, and point-to-point functions into a single chip, while RFID must be composed of a reader and a tag. RFID can only realize information reading and judgment, while NFC technology emphasizes information interaction. In layman's terms, NFC is an evolved version of RFID, and the two parties can exchange information at close range. The NFC mobile phone has a built-in NFC chip, which forms a part of the RFID module, and can be used as an RFID passive tag for payment; it can also be used as an RFID reader for data exchange and collection, and data communication between NFC mobile phones.

Second, the transmission range of NFC is smaller than that of RFID. The transmission range of RFID can reach several meters or even tens of meters. However, due to the unique signal attenuation technology adopted by NFC, NFC has the advantages of short distance, high bandwidth, and low energy consumption compared with RFID. Features.

Third, the application direction is different. NFC is more aimed at communicating with consumer electronic devices, while active RFID is better at long-distance identification.

With the popularization of the Internet, mobile phones, as the most direct intelligent terminals on the Internet, will definitely cause a technological revolution. Like Bluetooth, USB, GPS, and other standard configurations in the past, NFC will become the most important standard configuration of mobile phones in the future. Through NFC Technology, mobile payment, watching movies, and taking the subway can all be realized and will play a greater role in our daily life.

Author: Written by Ms.Anna Zhang from S4A INDUSTRIAL CO., LIMITED