Near-field (or nearfield) communication (NFC) is a set of standards for smartphones and other mobile devices to establish radio communication with each other by touching them together or bringing them into close proximity, usually no more than a few centimeters.
Current NFC systems use a radio frequency of 13.56 MHz, corresponding to a wavelength of 22.11 m. To efficiently generate a far-field, which means to send out radio waves of this wavelength, one typically needs an antenna of a quarter wavelength, in practice a meter or more. If the antenna is just a few centimeters long, it will only set up the so-called near-field around itself, with length, width, and depth of the field roughly the same as the dimensions of the antenna. Very little energy will radiate away, it is essentially a stationary electromagnetic field pulsating at 13.56 MHz. If you bring another similarly small antenna into this field, you will induce an electric potential into it, alternating at the said frequency. By modulating the signal in the active antenna, one can, of course, transmit a signal to the passive, receiving antenna. Present and anticipated applications include contactless transactions, data exchange, and simplified setup of more complex communications such as Wi-Fi. Communication is also possible between an NFC device and an unpowered NFC chip, called a tag.
Uses
NFC builds upon RFID systems by allowing two-way communication between endpoints, where earlier systems such as contactless smart cards were one-way only. It has been used in devices such as Google Nexus, running Android 4.0 Ice Cream Sandwich, named with a feature called Android Beam which was first introduced in Google Nexus.
Social networking
NFC can be used in social networking situations, such as sharing contacts, photos, videos or files, and entering multiplayer mobile games.
Commerce
NFC devices can be used in contactless payment systems, similar to those currently used in credit cards and electronic ticket smartcards, and allow mobile payment to replace or supplement these systems.
With the release of Android 4.4, Google introduced new platform support for secure NFC-based transactions through Host Card Emulation (HCE), for payments, loyalty programs, card access, transit passes, and other custom services. With HCE, any app on an Android 4.4 device can emulate an NFC smart card, letting users tap to initiate transactions with an app of their choice. Apps can also use a new Reader Mode so as to act as readers for HCE cards and other NFC-based transactions.
On September 9, 2014, Apple also announced support for NFC-powered transactions as part of their Apple Pay program.
Current NFC systems use a radio frequency of 13.56 MHz, corresponding to a wavelength of 22.11 m. To efficiently generate a far-field, which means to send out radio waves of this wavelength, one typically needs an antenna of a quarter wavelength, in practice a meter or more. If the antenna is just a few centimeters long, it will only set up the so-called near-field around itself, with length, width, and depth of the field roughly the same as the dimensions of the antenna. Very little energy will radiate away, it is essentially a stationary electromagnetic field pulsating at 13.56 MHz. If you bring another similarly small antenna into this field, you will induce an electric potential into it, alternating at the said frequency. By modulating the signal in the active antenna, one can, of course, transmit a signal to the passive, receiving antenna. Present and anticipated applications include contactless transactions, data exchange, and simplified setup of more complex communications such as Wi-Fi. Communication is also possible between an NFC device and an unpowered NFC chip, called a tag.
Uses
NFC builds upon RFID systems by allowing two-way communication between endpoints, where earlier systems such as contactless smart cards were one-way only. It has been used in devices such as Google Nexus, running Android 4.0 Ice Cream Sandwich, named with a feature called Android Beam which was first introduced in Google Nexus.
Social networking
NFC can be used in social networking situations, such as sharing contacts, photos, videos or files, and entering multiplayer mobile games.
Commerce
NFC devices can be used in contactless payment systems, similar to those currently used in credit cards and electronic ticket smartcards, and allow mobile payment to replace or supplement these systems.
With the release of Android 4.4, Google introduced new platform support for secure NFC-based transactions through Host Card Emulation (HCE), for payments, loyalty programs, card access, transit passes, and other custom services. With HCE, any app on an Android 4.4 device can emulate an NFC smart card, letting users tap to initiate transactions with an app of their choice. Apps can also use a new Reader Mode so as to act as readers for HCE cards and other NFC-based transactions.
On September 9, 2014, Apple also announced support for NFC-powered transactions as part of their Apple Pay program.
No comments:
Post a Comment