This article explains how radio waves are being utilized in our everyday lives through technologies like RFID and NFC. We’ll cover how RFID and NFC work, their various applications, and how they’re transforming modern life.
When most people hear the word “radio,” they think of radio stations with deejays or DMBs. However, radio is more than just a broadcast medium; it also refers to the technology of radio waves and communication. Radio waves are utilized in a wide range of technologies today and are deeply embedded in our daily lives. For example, when you check out a book from the library, you don’t have to scan the barcode of each book; you can simply stack several books in a self-checkout machine and they will be automatically recognized and checked out. In addition, at toll gates, vehicles automatically pay the toll as they pass without stopping, and on buses, transportation cards are replacing tokens. All of this is thanks to radio waves, specifically RFID (Radio Frequency Identification) technology. RFID is making our lives easier, and in this article, we’re going to take a look at the everyday “radio” technology that we’ve been ignoring, RFID, and its evolution into NFC.
First, let’s take a closer look at RFID. In a nutshell, RFID is about giving objects that can’t speak a voice with a unique frequency that can convey brief information. Objects with these unique frequencies can send and receive information without direct contact with a terminal. For example, a transportation card can communicate the rider’s age and card balance to a transportation card terminal even if it is in a wallet or bag, and a student ID card can prove to a library door that the cardholder is a student even if it is in a wallet. In this way, RFID is deeply embedded in our daily lives without us even realizing it.
RFID basically consists of a tag that acts as an object’s vocal cords, an antenna that acts as an ear to hear voices and a mouth to issue commands, and a reader that understands what the object is saying. It’s important to note that RFID uses radio waves at a set frequency to communicate, not sound. The process begins when a tag attached to or embedded in an object transmits a specific frequency of radio waves. This radio wave contains 96 bits of information, including the type of RFID device, its unique number, and the information to be sent and received, and is received by an antenna tuned to the correct frequency. The received information is processed by the reader, and if necessary, the antenna sends out another radio wave with information to modify the information stored in the tag.
RFID can be broadly categorized into active and passive RFID, depending on how the tag is powered. Active RFID is a type of RFID that is powered directly by the tag, which allows it to continuously transmit information in a loud voice. Because of this, active RFID is used in applications that require relatively long-distance communication, such as object location tracking and high-pass systems. Passive RFID, on the other hand, uses tags that are temporarily powered by an induced current from a terminal, and is typically used for cards that don’t require a power supply, such as transit cards or student IDs.
RFID is also categorized by the frequency bands it uses. Low-frequency (LF) RFID is low-cost but has a very short communication distance and slow information transfer, which is why it’s used in livestock management. On the other hand, RFID using UHF (Ultra High Frequency) frequency has a long communication distance and high information transmission speed, which is used for high-speed sports scoring. RFID using the HF (High Frequency, 13.56 MHz) frequency has not been widely used due to the lack of a balance between cost and performance, but the recent development of NFC technology has increased its utilization.
Let’s take a look at NFC. NFC is a more advanced technology that addresses the limitations of RFID, turning short communication distances into high security. You can exchange business cards, make payments, and even use your phone as a transportation card just by holding it up to each other. NFC is different from RFID in that it can communicate with each other. While RFID terminals only have an antenna and a reader, and the tags are separate, NFC devices combine a tag, antenna, and reader. This allows NFC devices to read and pass on information from other tags, and vice versa, to be read by other NFC devices. It’s like how beepers (RFID) evolved into cell phones (NFC) that can send and receive texts.
However, there are still challenges that need to be addressed before NFC can usher in an era where smartphones replace wallets. One of them is the lack of security. Despite the fact that NFC communicates over a short distance and the information is encrypted, the technology is not 100% secure because it is based on long-distance communication. For example, if a hacker uses an NFC device to scan people’s bags or pockets on a crowded subway, a lot of personal information could be compromised in an instant. For this reason, NFC is currently mostly used for transportation cards, where it’s not likely to be compromised. However, with major card companies like PayPal, Visa, MasterCard, and American Express investing to address security concerns, it’s likely that smartphones will replace wallets in the near future.
It’s important for us to understand and adapt to the rapidly changing landscape of technology. While we enjoy the convenience of RFID and NFC, we need to recognize and prepare for the risks that lie behind them. While radio used to connect people through music, stories, and images, radio waves are now connecting people, machines, and objects to make our lives easier and smarter.
