0 Preface
IC cards are often seen in our daily lives. Its development has experienced contact memory cards and encryption cards, and is now developing in the direction of contactless cards and CPU cards. The wireless IC card uses a non-contact method, which uses radio frequency technology to realize communication between the radio frequency card and the reading and writing device, and has a large working distance, no contact, fast information processing, etc. compared with early or synchronous recognition technologies such as bar code and magnetic card. Advantages, so this high-tech products can be widely used in household appliances, identity control, burglar alarm, electronic security labels, animal ear tag classification, etc., in addition to applications in confidential and financial products. This paper takes the BL75R06SM radio frequency identification chip with the working frequency of 13.56MHz as an example to introduce the advantages, basic components, working principle and application of the radio frequency card.
1 Advantages of wireless RF card
Radio Frequency Identification (RFID) is a non-contact automatic identification technology. Its basic principle is to use the spatial coupling and propagation characteristics of radio frequency signals and electromagnetics to realize automatic recognition of recognized objects. Multidisciplinary, multi-technology application technology. Wireless IC card, also known as convenience card, radar card, proximity card, contactless card, RF card, magic card, RF card, smart card, it combines radio frequency identification technology and IC card technology to solve the passive ( The problem of no power in the card and contactlessness is a major breakthrough in the field of electronic devices. It has the following advantages:
(1) The wireless IC card has high reliability. It has no mechanical contact with the reader, avoiding various faults caused by contact with the reader. For example, rough card insertion, non-card foreign object insertion, dust or oil stains lead to misreading of cards or poor contact.
(2) Since there is no exposed chip on the surface of the IC card, there is no need to worry about chip falling off, electrostatic breakdown, bending damage and the like.
(3) Easy to operate. It can be used for two-way trading with the reader in the range of less than 10ms from the reader's 30~200mm range. Therefore, the bus card can still be traded in the wallet.
(4) The transaction speed is fast. It has a fast anti-collision mechanism to prevent data interference between cards. Its read/write time is less than 10ms, and the time for authentication and transaction is less than 100ms.
(5) The encryption performance is good. The chip has 64-bit data, including another 9-bit header, 40-bit data content and 14-bit check digit, and a stop bit. Its serial number is unique. The manufacturer's chip has already sequenced this chip before leaving the factory. No. Curing, can not be modified once cured. A two-way authentication mechanism is adopted between the IC card and the reader, that is, the reader verifies the legality of the IC card, and the illegal card cannot enter the system for transaction, and has strong security, confidentiality and usability.
2 BL75R06 features
The BL75R06SM is an 8kbE2PROM contactless encryption storage IC card chip. It consists of a radio communication interface, a digital logic control module (including a security control unit) and an 8kb E2PROM memory integrated on a Die. Figure 1 shows the internal topology of the BL75R06. The chip is directly connected to an antenna composed of coils for wireless transmission, and the read/write distance is 10 cm.
.jpg)
The RF communication interface part is composed of a radio frequency communication interface, rectification, voltage regulation, modulation/demodulation, power-on reset and clock, which are introduced by the antenna; the digital logic control module is required to respond, anti-collision, application selection, authentication and access. Control, control and arithmetic unit, RAM, ROM, crypto unit, etc.; E2PROM memory part consists of interface and 8kb E2PROM memory.
The RF interface of BL75R06 meets the requirements of ISO/IEC14443TypeA. The chip does not need a battery. The energy transmitted by the reader can be activated. The ID number and required information data in the chip can be wirelessly transmitted. The operation distance can reach 10cm. Of course, the distance is The geometry of the antenna is related to the efficiency; the operating frequency is 13.56MHz; the data transmission rate is 106kbps; the 16-bit CRC check, parity, bit coding, bit count, etc. ensure the integrity and reliability of the transmitted data; typical transaction time , including backup management time less than 100ms. The E2PROM is divided into 16 sectors, each sector is divided into 4 blocks of 16 bytes each; the access conditions of each memory block can be defined by the customer; the data retention time is at least 10 years; and the number of erasures is at least 100,000 cycles.
The BL75R06 supports the IS014443TypeA RF interface and supports the PHILIPS standard reader chip.
3 IC card's main structure and security system
The IC card is mainly composed of a copper-frame loop antenna similar to a printed circuit board corrosion-molded and a bare chip (see FIG. 2) bound thereto, and a card-side two-sided color plastic package.
.jpg)
The shape and number of turns of the IC card are related to the operating frequency. It requires accurate calculations, rich practical experience, and matching with the chip. In the original design, a network analyzer is required to verify and adjust the antenna geometry and network matching.
In order to provide a high level of security, the BL75R06 uses a triple mutual authentication system that complies with the ISO/IECDIS9798-2 protocol:
(1) The card reader first determines the sector to be accessed, and then selects the key A or the key B;
(2) The first weight is that the card reads the key and access conditions from the Trailer block of the sector and sends a random number to the reader:
(3) The second weight is the card reader's key and the additional input to calculate the card's response, and then send a response and another random number to the card;
(4) The third weight is the response of the card verification card reader, and then a response is calculated and sent to the card reader;
(5) The card reader re-verifies the response of the card;
After performing the above steps and sending the first random number, the communication between the card and the reader is encrypted.
4 Communication working principle
Radio frequency identification (RFID) is an abbreviation for radio frequency identification, that is, identification processing by radio waves. The RFID system usually consists of a card reader (reader) and a transponder (card). The basic composition is shown in Figure 3. The card reader is also called a non-contact IC card reading and writing terminal, and is generally composed of a power source, a microprocessor, an antenna board, etc., and is connected to a computer through a peripheral interface. The transponder is a contactless card with an induction coil (antenna) and a memory for storing application identification information. The card itself does not have a power supply. When the card enters the electromagnetic field of the reader, it can pass. The energy of the radio wave is coupled, and the working power is obtained after being rectified and regulated.
.jpg)
The working process of the wireless RF card is:
(1) The card reader continuously sends a set of electromagnetic waves with a fixed frequency of 13.56 MHz.
(2) The antenna of the wireless radio frequency card with the BL75R06 chip has the same resonant frequency as the signal sent by the reader. When it enters the working area of ​​the card reader, the resonant circuit resonates under electromagnetic excitation.
(3) Resonance causes the capacitance inside the card to be loaded. At the other end of the capacitor, a single-pass electronic pump is connected to store the charge in the capacitor to another capacitor. When the accumulated charge reaches 2V, This capacitor acts as a power source to supply the operating voltage to the integrated circuit.
(4) The BL75R06 chip interacts with the card reader through the antenna, and the command is sent by the card reader. The digital logic control module inside the BL75R06 determines the operability of the command according to the access control conditions of the corresponding sector to be accessed. Send the appropriate information or data.
(5) The card reader sends a request response command to all the cards in the work area RF field. After the smart card is powered on, it can respond to the request command according to the ATQA of the IS0/IEC14443A protocol. During the anti-collision cycle, the card reader reads the ID serial number of the card. If the card reader has several cards in its working range, it can be identified by a unique card ID serial number, and one of the cards is selected. As the object of the next operation, the unselected card returns to the standby mode and waits for the next request command.
(6) After the card reader issues the card selection command, a card is selected to authenticate and operate on the associated memory, and the card returns an ATS code indicating the type of the selected card. After the card is selected, the card reader uses the response key to perform the triple mutual authentication process according to the memory location to be accessed. After the authentication is passed, the operation of the memory is encrypted. After the authentication is passed, the operations of reading blocks, writing blocks, adding, subtracting, restoring, transferring, and terminating are performed. Add is to add a value to the contents of the block, and save the result to a temporary data register; subtract is to subtract a value from the contents of the block, and save the result to a temporary data register; recovery is Move the contents of the block to a temporary data register; transfer is to write the contents of the temporary register to the specified block. The wireless communication between the card reader and the smart card is a 16-bit CRC using information blocks, and a parity bit for each byte to ensure the reliability of data transmission. The transaction process of the card reader and smart card communication is shown in Figure 4.
.jpg)
5 Wide application of wireless RF cards
The radio frequency card works in the near-field distance, and obtains energy and downlink commands from the transmitting antenna through the inductive coupling of the smart card antenna and the card reader antenna (a transformer-like coupling), using load modulation (Load Modulation) method. The reader returns data, and the higher the operating frequency, the faster the communication between the reader and the card, and the shorter the system's working time.
In recent years, 13.56MHz RFID radio frequency cards are increasingly winning the market for various smart cards, consumer cards, and theme cards. Shopping cards, campus cards, Internet cafe cards, telephone cards, fuel cards, parking cards, bus cards, access cards, etc. have been in close contact with people's lives, mainly for various documents, electronic wallets, automatic toll collection systems and public transportation vending In the field of ticket checking systems, it has become an indispensable electronic wallet and an important identification document. The chip supports IS014443 TypeA RF interface and supports PHILIPS standard card reader chip. The wide application of proximity contactless cards has led to a non-contact transition from contact to close proximity in the gold card market. It is expected that the 13.56 MHz RFID proximity contactless card market will grow rapidly.
Lip Makeup,Liquid Lipgloss,Lip Gloss,Lipstick Or Lipgloss
Suzhou Yimeijia368 Biological Technology Co.,Ltd. , https://www.szymjbeauty.com