5. What are contactless credit cards?
Contactless credit cards differ from regular credit cards in the way the information is read from them by the card reader. A regular credit card stores its data on a magnetic stripe that must be physically swiped through a card reader. A contactless credit card, on the other hand, stores its data on a microchip embedded in the card's plastic. The microchip is fitted with a radio antenna that is capable of transmitting the card's data to a card reader without physical contact. Using radio frequency identification (RFID) technology with the ISO 14443 standard, a contactless card can transmit data to a special RFID card reader when the cardholder waves his card within a few inches of the receiver.
6. What are the differences between ISO 14443A, 14443B and C proximity coupling smart cards?
ISO 14443 has two variants, Type A and Type B. ISO 14443A was accepted by the ISO committee in 1997. It is the first ISO standard for 13.56 MHz frequency contactless card which was developed by Mikron Austria and acquired by Phillips in 1996. Currently, ISO 14443A is the most widely used contactless standard in the world, mainly in transport applications.
ISO 14443B was approved by the ISO committee in 1998. ISO 14443B has a number of advantages over ISO 14443A:
1. Unlike ISO 14443A uses 100% modulation depth, it means that the reader stops emitting the field for defined periods of time. The modulation depth for ISO 14443B is only 10% which preserves the continuity of the clock.
2. No patents on communication coding.
3. Communication speeds of up to 847 KHz.
4. Adopted as a national standard by many countries, such as US, China, Japan, etc.
A third variant of the ISO 14443 standard, Type C, was developed by Sony, however, it was abandoned by the ISO/IEC committee and now is renamed as Felica.
*Securitag Assembly Group (SAG) is able to provide ISO 14443 proximity coupling smart cards and tags with the following RFID technologies:
ISO 14443A: Mifare 1K, Mifare 4K, Mifare Ultralight, Mifare DESFire, SLE66R35
ISO 14443B: AT88RF020, SR176, SRIX512, SRIX4K
Felica (ISO 14443C): RC-S919
7. What is RFID?
Radio frequency identification (RFID), is a generic term for technologies that use radio waves to automatically identify people or objects. It commonly works with a compute information system as advanced means to control or manage terminal articles or people.
RFID is composed of microchip and antenna with various encapsulations to adapt different environment in application. The antenna enables the chip to communicate with the identification information to a reader in air by contactless digital information transfer. For long lifespan and low cost thinking, most of RFID product in common use are passive RFID, it means no battery enclosed in, and it get the power from corresponding frequency wave energy of reader.
RFID is a new technique emerging to business application with 10ten year. We have great confidence from these years experience and progress with process of innovation which rapidly accumulated. Nevertheless, the advent of high-performance, facile, low-cost, RFID technology is absolutely central to the ability to conduct information warfare and information operations today.
8. Where will the initial benefits of RFID technology be?
RFID technology can deliver benefits in many areas, from tracking work in process to speeding up throughput in a warehouse. Radio-frequency identification (RFID) is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags or transponders.
An RFID tag is an object that can be stuck on or incorporated into a product, animal, or person for the purpose of identification using radiowaves. Some tags can be read from several meters away and beyond the line of sight of the reader.
Most RFID tags contain at least two parts. One is an integrated circuit for storing and processing information, modulating and demodulating a (RF) signal and perhaps other specialized functions. The second is an antenna for receiving and transmitting the signal. A technology called chipless RFID allows for discrete identification of tags without an integrated circuit, thereby allowing tags to be printed directly onto assets at lower cost than traditional tags.
Today, a significant thrust in RFID use is in enterprise supply chain management, improving the efficiency of inventory tracking and management.
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9. What is passive RFID tag?
A passive tag is an RFID tag that does not contain a battery; the power is supplied by the reader. When radio waves from the reader are encountered by a passive rfid tag, the coiled antenna within the tag forms a magnetic field. The tag draws power from it, energizing the circuits in the tag. The tag then sends the information encoded in the tag's memory. The advantages of a passive RFID tag are:
The tag functions without a battery; these tags have a useful life of twenty years or more.
The tag is typically much less expensive to manufacture
The tag is much smaller (some tags are the size of a grain of rice). These tags have almost unlimited applications in consumer goods and other areas. The major disadvantages of a passive rfid tag are: The tag can be read only at very short distances, typically a few feet at most. This greatly limits the device for certain applications. It may not be possible to include sensors that can use electricity for power. The tag remains readable for a very long time, even after the product to which the tag is attached has been sold and is no longer being tracked.
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10. What is the difference between EM4102 and EM4100?
About the electrical function, there is no difference between EM4100 and EM4102. Both RFID chips work at 125 KHz and with 64 bit read only memory size. The major differences are that EM4102 chip has gold bumps on the die and there is a bit smaller response capacitance and more wire turns. So EM4102 is much expensive and good at long distance reading.
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11. What are some of the most common applications for RFID?
RFID is used for everything from tracking cows and pets to triggering equipment down oil wells. It may sound trite, but the applications are limited only by people's imagination. The most common applications are payment systems (Mobil Speedpass and toll collection systems, for instance), access control and asset tracking. Increasingly, retail/CPG and pharma companies are looking to use RFID to track goods within their supply chain, to work in process and for other applications.
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12. How do I know which frequency is right for my application?
Different frequencies have different characteristics that make them more useful for different applications. For instance, low-frequency tags use less power and are better able to penetrate non-metallic substances. They are ideal for scanning objects with high-water content, such as fruit, but their read range is limited to less than a foot (0.33 meter). High-frequency tags work better on objects made of metal and can work around goods with high water content. They have a maximum read range of about three feet (1 meter). UHF frequencies typically offer better range and can transfer data faster than low- and high-frequencies. But they use more power and are less likely to pass through materials. And because they tend to be more "directed," they require a clear path between the tag and reader. UHF tags might be better for scanning boxes of goods as they pass through a dock door into a warehouse. It is best to work with a knowledgeable consultant, integrator or vendor that can help you choose the right frequency for your application.
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13. What is the difference between low-, high-, and ultra-high frequencies?
Just as your radio tunes in to different frequencies to hear different channels, RFID tags and readers have to be tuned to the same frequency to communicate. RFID systems use many different frequencies, but generally the most common are low-frequency (around 125 KHz), high-frequency (13.56 MHz) and ultra-high-frequency or UHF (860-960 MHz). Microwave (2.45 GHz) is also used in some applications. Radio waves behave differently at different frequencies, so you have to choose the right frequency for the right application.
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14. How does an RFID system work?
An RFID system consists of a tag made up of a microchip with an antenna, and an interrogator or reader with an antenna. The reader sends out electromagnetic waves. The tag antenna is tuned to receive these waves. A passive RFID tag draws power from the field created by the reader and uses it to power the microchip's circuits. The chip then modulates the waves that the tag sends back to the reader, which converts the new waves into digital data. For more information on the components of a complete system used in businesses, see Getting Started.
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15. I've heard that RFID doesn't work around metal and water. Does that mean I can't use it to track cans or liquid products?
Radio waves bounce off metal and are absorbed by water at ultrahigh frequencies. That makes tracking metal products, or those with high water content, difficult. However, good system design and engineering is beginning to overcome this shortcoming. Low- and high-frequency tags work better on products with water and metal. In fact, there are applications in which low-frequency RFID tags are embedded in metal auto parts to track them. Moreover, the introduction of foam-attached tags (FAT tags) from such companies as ADASA and SAVR Communications has helped reduce the impact of metal on RFID systems (see New RFID Products for Coping with Metal), while QinetiQ and Crown Holdings have worked to develop soft-drink cans and other metal containers with built-in EPCglobal Gen 2 UHF RFID tags designed to circumvent RF interference (see QinetiQ and Crown Develop Item Containers With Antenna-less RFID Tags). There are also ways to tag products with metal or water content to ensure reliabile read rates (members, see How to Tag Problem Products.
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16. What is tag collision?
Tag collision occurs when more than one transponder reflects back a signal at the same time, confusing the reader. Different vendors have developed different systems for having the tags respond to the reader one at a time. These involve using algorithms to "singulate" the tags. Since each tag can be read in milliseconds, it appears that all the tags are being read simultaneously.
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17. What's the difference between passive and active tags?
Active RFID tags have a transmitter and their own power source (typically a battery). The power source is used to run the microchip's circuitry and to broadcast a signal to a reader (the way a cell phone transmits signals to a base station). Passive tags have no battery. Instead, they draw power from the reader, which sends out electromagnetic waves that induce a current in the tag's antenna. Semi-passive tags use a battery to run the chip's circuitry, but communicate by drawing power from the reader. Active and semi-passive tags are useful for tracking high-＆#118alue goods that need to be scanned over long ranges, such as railway cars on a track, but they cost more than passive tags, which means they can't be used on low-cost items. (There are companies developing technology that could make active tags far less expensive than they are today.) End-users are focusing on passive UHF tags, which cost less than 40 cents today in volumes of 1 million tags or more. Their read range isn't as far—typically less than 20 feet vs. 100 feet or more for active tags—but they are far less expensive than active tags and can be disposed of with the product packaging.
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18. What is the read range for a typical RFID tag?
There really is no such thing as a "typical" RFID tag, and the read range of passive tags depends on many factors: the frequency of operation, the power of the reader, interference from other RF devices and so on. In general, low-frequency tags are read from a foot (0.33 meter) or less. High-frequency tags are read from about three feet (1 meter) and UHF tags are read from 10 to 20 feet. Where longer ranges are needed, such as for tracking railway cars, active tags use batteries to boost read ranges to 300 feet (100 meters) or more.
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19. What's the difference between read-only and read-write RFID tags?
Microchips in RFID tags can be read-write, read-only or “write once, read many” (WORM). With read-write chips, you can add information to the tag or write over existing information when the tag is within range of a reader. Read-write tags usually have a serial number that can't be written over. Additional blocks of data can be used to store additional information about the items the tag is attached to (these can usually be locked to prevent overwriting of data). Read-only microchips have information stored on them during the manufacturing process. The information on such chips can never be changed. WORM tags can have a serial number written to them once, and that information cannot be overwritten later. Microchips in RFID tags can be read-write, read-only or “write once, read many” (WORM). With read-write chips, you can add information to the tag or write over existing information when the tag is within range of a reader. Read-write tags usually have a serial number that can't be written over. Additional blocks of data can be used to store additional information about the items the tag is attached to (these can usually be locked to prevent overwriting of data). Read-only microchips have information stored on them during the manufacturing process. The information on such chips can never be changed. WORM tags can have a serial number written to them once, and that information cannot be overwritten later
