NFC Antennas

What are NFC antennas?

NFC antenna is one of the core components of Near Field Communication (NFC) technology, which is mainly used to realize short-range wireless communication between devices.

NFC antenna is not an “antenna” in the traditional sense (such as dipole antenna or horn antenna), but a device that transmits and receives signals by inducing electromagnetic fields.

NFC antenna generally consists of a circuit coil made by wire-winding/printing/etching process with ferrite material for anti-interference capability.

NFC stands for Near Field Communication. It is a contactless identification and interconnection technology that enables near-field communication between mobile devices, consumer electronics, PCs, and smart control tools.

NFC provides a simple, touch-enabled solution that allows consumers to exchange information and access content and services simply and intuitively.NFC consists of an NFC module and an NFC antenna. The NFC module generally consists of a high-speed microcontroller, an RF chip, and matching circuitry.

NFC antenna working principle

The working principle of the NFC antenna is mainly based on electromagnetic induction and RFID radio frequency identification technology. When an NFC device is close to an NFC tag, the NFC antenna captures the weak electromagnetic field signals emitted by the tag and converts these signals into electrical signals for processing.

These signals are usually generated by the RFID chip in the tag, which usually operates at a frequency of around 13.56MHz. The captured EMF signals are amplified, filtered, sampled quantized, converted into digital signals, and sent to the NFC controller for processing.

In the controller, the digital signal is decoded and compared with pre-stored information, and if the match is successful, the appropriate operation (e.g., payment, data transfer, etc.) is performed.

Signal capture

The NFC antenna captures the electromagnetic field signals emitted by the tag, which are usually generated by the RFID chip in the tag and operate at frequencies between 13.56MHz and 106.7MHz.

Converting the signals

The captured EMF signals are amplified, band-pass filtered, sampled, and quantized, and converted into digital signals for subsequent processing.

Data processing

The digital signal is sent to the NFC controller for processing, decoded, and compared with the pre-stored information, and if the match is successful, the corresponding operation (e.g., payment, data transmission, etc.) is executed

NFC antenna structural characteristics

An NFC antenna usually consists of a coil of conductive material capable of transmitting and receiving signals by inducing an electromagnetic field.

When two NFC devices are close to each other, their NFC antennas will interact with each other to realize data transmission.NFC antenna’s operating frequency is 13.56MHz, and the radiation efficiency is very low, so its performance mainly depends on the size of the inductance, the larger the inductance, the better the performance.

In addition, the design of the NFC antenna needs to consider several factors, such as the number of turns of the coil, the alignment width, the gap width, etc., which all affect its electrical parameters (e.g., inductance, resistance, self-resonant frequency, etc.), and thus the performance of the NFC antenna.

NFC antenna applications

NFC antenna is widely used in many fields, such as mobile payment, access control systems, e-ticketing, identification, and so on. Its advantage is that no physical contact can realize data transmission and identification, which improves the convenience and security of operation.

At the same time, NFC antenna also has the characteristics of low cost, low power consumption, ease of integration, and so on, which makes it also a broad application prospect in the field of the Internet of things, smart homes, and so on.

Who manufactures NFC antennas?

C&T RF Antennas Inc. manufactures NFC antenna styles for your choice. Contact us for off-the-shelf CBRS antennas or design customizations.