Wednesday, December 29, 2010
【 Weak current College 】 contactless smart card applications in the city-card key technology 】
Non-contact card is the most popular application when an urban public transport system, the current global with more than 100 cities to introduce contactless transit payments, contactless IC card application of the transit system has greatly contributed to the non-contact IC card development, become a leading IC manufacturers must place.
But as the city card system of development and maturity, a cartoon system is no longer limited to the use of public transit system, for non-contact IC card, apply extensibility and security have a higher demand. Contactless smart cards for their high security characteristics begin to attention. April this year, held in Kunming, the national public transport IC card to meet supply and demand, watchdata latest non-contact CPU card becomes the focus of the entire Conference.
Watchdata in contactless smart card technology has been very mature, earlier had already developed and launched the TimeCOS/DI dual interface cards, a card, two kinds of communication: contact and contactless. With the traditional advantages of the smart card, you also have the contact card and contactless card advantage watchdata this dual-interface card in municipal transit system has been expanded application, there is a typical case of Suzhou city card, Dalian bus card, etc.
Recently, after a long gestation of NFC began formal public trial, watchdata dual interface smart card technology SIMpass mobile contactless solution also launched an internal evaluation, non-contact smart card development has entered the fast-track.
Contactless smart card came into being
Today, contact IC card in the people's daily lives in the universal application. In the contact type IC card popularity, gradually found many disadvantages: card reader often wear lead seated poor contact, thus causing data transmission errors, and the card and reader of wear also greatly shortens the card and the reader's life; in addition, the contact type IC calorie distribution rate is lower, plus swap cards action delay caused each transaction takes a long time of waiting. In order to solve these problems, watchdata Unveils contactless smart card.
More and more applications in addition to the non-contact card of interface requests, the traditional non-contact card application development made a further request. Original non-contact card of the directive is relatively simple, the feature is relatively small. To complete a complex operations such as creating a file needed for non-contact card's data structures is very aware of and you want to write a lot of instruction. Especially non-contact card kept much of the information is sensitive, such as the amount and the like, such information to read or write, if an unexpected interruption of the operation, how to recover information from a headache, this requires a high software skills. All of which greatly hindered the non-contact card application development. Therefore watchdata in non-contact card integrated into the CPU, COS software to provide a simple, powerful application development interface is a very good solution.
Contactless smart card works
Contactless smart cards, also known as RF card, is the world in recent years developed a new technology, it succeeded in RFID and smart card technologies to solve a non-powered (no power in the card) and avoid contact with this challenge, is the electronic devices a breakthrough in the field.
Non-contact systems generally consist of non-contact smart cards and readers, as well as control modules.
Watchdata launched contactless smart card, chip and antenna is fully encapsulated in the card itself, this kind of card surface no-contact, through electromagnetic induction methods to communicate with the reader. To comply with the ISO14443 standard contactless smart card, to the reader (PCD, close-coupled device) data transmission by using amplitude shift keying (OOK) modulation Manchester encoding (TypeA) and phase-shift keying (BPSK) modulation of non-zero encoding (TypeB).
Reader (Reader), mainly by wireless transceiver modules, antennas, control module and interface circuits, etc. The reader can read and write commands are delivered to the non-contact smart cards and analyzes the response data. To comply with the ISO14443 standard machines, to the non-contact smart cards (PICC, close to the smart card) data transfer using difference is 100% ASK modulation of improved Miller encoding (TypeA) and 10% ASK modulation of non-zero encoding (TypeB).
System according to the operating frequency to 13.56MHz half duplex mode at non-contact smart cards and readers for two-way data transfer between. Reader will control module (host) to send information, encoded loaded at a frequency of the carrier signal, the antenna to send, enter the card reader work area for non-contact smart cards receive this pulse signal, card chip in the circuit on this signal modulation, decode, decryption, and then on the order request, passwords, permissions, etc. to determine and respond.
On the other hand, the reader of the carrier signal contains power signal, the signal from the non-contact smart cards receive, and the L/C itself produces resonance, an instant energy to supply chip work for non-contact smart cards provide a power supply. Data exchange and data management system is mainly done on information storage and management, on-card read/write control, etc.
Contactless smart card's many features
And contactless IC card, contactless smart card has many advantages:
? High reliability, long service life
Card and reader, without mechanical contact between avoids contact with read and write various fault arising. Especially in some conditions, interfere with great environment, due to its completely sealed package, not only can prevent gross card, non-card for foreign objects inserted, dust, and oil, etc., resulting in poor contact, but also provides water vapor, anti-static, anti vibration and anti-EMI's excellent features.BR>
Easy and fast?
Due to the use of contactless communication method, reader in a range of operations on the card, so you don't have to swap cards and contactless smart card use is not directional, cards are free direction passing reader surface, complete one only needs to be 0.1 seconds, this greatly improves the speed of each use.
· Conflict prevention, anti-jammings well, can simultaneously handle more than one card
There is a mechanism for conflict prevention, can effectively prevent the card data interference between the card "at the" within access read-write, read-write device can be a pair of cards processed. This improves application of parallelism, but also virtually increases the speed of the system work.
Non-contact smart cards and reader between two-way authentication mechanism and third mutual recognition; and in the communication process, all data is encrypted; in addition, the card in each region has its own password and access conditions for the operation.
Suitable for multiple applications?
Watchdata launched contactless smart card storage structure characteristics enable it to achieve the city pass card smart card needs; such as: electronic purse/passbook, bus, taxi, Metro, garden areas, highways general road, bridge tolls, or applications. Each application can set different passwords and access conditions, the system configuration is quite flexible.
Contactless smart card technology in a number of key
Contactless smart cards work characteristics, reflected in the design, safety and manufacture of some technical difficulties, mainly concentrated in the chip manufacturing, security system and card encapsulation.
1, radio frequency technology (coil and antenna design)
Contactless smart card is the world's most advanced radio frequency technology and IC card technology, domestic demand has with a special card design of antenna, and buried in card; you must ensure that there is a good anti-jamming performance, but also with "anti-conflict" circuit. Identify the card distance depends primarily on the equipment of the antenna design and smart card of the coil design, so as the outstanding smart card, antenna design and is also one of the key technologies.
2. low power consumption technology
Either way as active or passive mode design of contactless smart card, one of the most basic requirements are needed to reduce power consumption to improve the life of the card and the expansion of applications, it can be said that reduce power consumption, with the guarantee of a certain distance is equally important. Thus the card chip is generally very demanding low-power technology and related technologies, such as circuit design using the "sleep mode" technology design and manufacturing.
3, packaging technology
Due to the non-contact IC card needs to be buried in Mount antennas, chips and other special parts, in order to ensure that the card size and thickness, flexibility and high-temperature and high-pressure process chip circuit security, require special packaging technology and specialized equipment. Due to the present main package with ABS, PVC, PVC + ABS, PET (PETG), etc, but there are easy to break, there are too soft, anti-aging effect is not good, it has an impact on the encapsulated coils. So find a have above-average performance of card-based materials is also a very important issue. But if the plus sign in the imaging, UnionPay, the entire system card process more complicated, the whole of the finished product rate would not be very high, so how to effectively increase the non-contact smart cards production yield world wide research.
4, security technology in addition to card communications security technology, but also to cards with chips of physical security technology and security technology card manufacturing this second aspect and the former constitutes a powerful security system. In a card structure, RF analog front end (RFAFE) shielding of the smart card's power, the clock, power-on reset (POR) signal from the rest of the world, to some extent reduces the attack. For such as SPA (SimplePowerAnalysis) and DPA (DifferentialPowerAnalysis) energy attack methods, for high security level for non-contact smart IC cards (such as watchdata of TimeCOSFLY), COS, as well as some key algorithm design, use random time moving, on a specified algorithm provides a clear formula, intermediate variables into two or more variables, and other methods to protect against attacks.