Lähietäisyystunnistus

Lähietäisyystunnistus, often translated as Near-Field Communication (NFC), is a wireless communication technology that allows two electronic devices to communicate with each other when they are brought within a very close proximity, typically a few centimeters or less. It is a subset of radio-frequency identification (RFID) technology and operates at a frequency of 13.56 MHz. NFC enables simple, secure communication between devices, making it suitable for a wide range of applications.

The core principle of NFC is based on inductive coupling. When two NFC-enabled devices are brought close together, they create a magnetic field that allows for data exchange. This close proximity requirement is a key security feature, as it prevents accidental or unauthorized communication. NFC operates in two main modes: active and passive. In active mode, both devices can generate their own radio frequency field and exchange data. In passive mode, one device provides the power and the radio frequency field, while the other device responds with its data.

NFC technology has found widespread adoption in various fields. In mobile payments, it allows users to make contactless transactions by simply tapping their smartphones or smartwatches on a payment terminal. It is also used for access control, such as unlocking doors or entering public transport with NFC-enabled cards or devices. Other applications include pairing devices like headphones or speakers quickly, transferring small amounts of data between phones, and providing interactive experiences with smart posters or product tags. The simplicity and security of NFC make it a convenient and growing part of everyday technology.