What is a NFC Tag?
The full name of NFC tag is near field communication, which means short-range wireless communication technology.
NFC tag is developed on the basis of non-contact radio frequency identification (RFID) technology and wireless interconnection technology. It provides a very safe and fast communication method for various electronic products that are becoming more and more popular in our daily life.
Short range wireless communication technology combines mobile communication technology and realizes various functions such as electronic payment, identity authentication, ticketing, data exchange, anti-counterfeiting and advertising. It is a new business in the field of mobile communication.
Simply put (non professional), it is a tag / label with electronic components inside, which can record some information. Usually, the storage capacity of about 1KB can meet common needs. When you approach (turn on NFC) the tag with your mobile phone, NFC will automatically scan the information contained in the tag, and then display the tag information on the mobile phone or execute the commands contained in the tag. Using NFC can provide some convenience. For example, when you get home, you want to connect to WiFi at home, and then log in to QQ. You can make such a tag / label yourself, and then paste it at the door of your home. As soon as you open the door at home and scan the tag / label with your mobile phone, the mobile phone will automatically execute the above commands. Of course, you can also use your imagination. For example, install the remote boot function on the mobile phone, and then make such a tag / label. Once you go home, the computer will open automatically. Of course, there are more ideas, as long as you can think of them.
Overall dimensions of NFC tag / label
NFC tag / labels are usually in the form of self-adhesive tag / labels. Although their appearance doesn’t make people feel very tall, it is because they are small and simple enough, which means that they can be used where other technologies can’t be used.
Each tag consists of two components that together form a functional device. One part is antenna and small system on chip (SOC).
During the interaction, the antenna receives external signals and activates the SOC. The SOC includes a micro CPU (central processing unit) and memory for storing information. The amount of memory depends on the tag, but is usually between 48 bytes and 1m bytes.
Because there is relatively little memory available, NFC tags are usually “encoded” as URLs or other text records. The NFC data exchange format (nDef) standard defines how to format this text to ensure interoperability between NFC chips and the devices that scan them.
Performance parameters of NFC tag
Because NFC tags operate offline, the technical role and specifications are completely different from the more traditional wireless communication technology based on far field that you are likely to know better. Let’s take a look at some interesting technical data information related to NFC and how to compare it with far-field wireless communication technology.
Although the dedicated point-to-point machine and equipment can reach above 100km under the condition of following the specifications, the typical 2.4GHz WiFi machine and equipment may be large, and the outdoor area is about 50-75m. When the wireless device operates on the same 2.4GHz WiFi, it will compromise the network bandwidth to improve the function loss, and expand the 5.0 version number to more than 300m. The scope of Lora machine equipment can exceed 10km, its function loss is far less than these two technologies, and the network bandwidth is very limited.
NFC is limited to 10cm by the design scheme.
Near field induction coil communication systems (such as NFC) have very severe power. The power is attenuated at a rate proportional to the number of to of the category of the sixth output power. This is much higher than far-field communication, so that when it is completed in the offline area of 13.56MHz (the most common frequency of NFC), its kinetic energy level is 10000 to 1000000 times lower than far-field communication (- 40dB to – 60dB). Intentional far-field FM transmitter with equivalent circuit.
Like all good standards, there are exceptions. Nfc5 label using iso-15693 protocol can load up to one meter spacing according to special hardware configuration; However, in fact, even if not all, most intelligent machines only follow the limit of 10cm. Some high-performance NFC wireless antennas allow tags with a spacing of no more than 15 cm, while on the other side of the band, some smaller tags limit the spacing to about 2 cm.
The reduced spacing results in physical postures that the user must establish in order for the protocol to work. In contrast to the online characteristics of WiFi and mobile Bluetooth from beginning to end, NFC is the only universal wireless communication protocol that can be applied only when customers adopt purposeful practical operation.
MHz is a measurement unit that we can’t expect to find in the wireless network specifications and models of contemporary intelligent machines. The iPhone 11 has a communication frequency of 8GHz, and 60GHz wigig machines and equipment are becoming more and more popular in the sales market. NFC uses different methods to reduce function loss, category, price and frequency.
Compared with the general high-speed connection, the relatively limited frequency and short route make the execution relativity of NFC wireless antenna free from pressure. In consideration of simplicity or inexperience, smart design staff are likely to expect to select a control module with integrated wireless antenna for mobile phone Bluetooth or WiFi. In the NFC industry, if you follow the proposal of IC, your design scheme is likely to perform well regardless of subtle manufacturing differences or surrounding objects (such as microwave heating frequency).
The larger network bandwidth applicable to NFC specification is 424K HD bit / s, which is about eight times the connection rate of traditional dialing 56K. This limitation makes the specification comparable to mobile Bluetooth in characteristics, about half of the data rate of version 4.0. Unfortunately, the specification costs a lot, and most machines and equipment generally operate at a rate of 50kbit / s. Even if the data rate on the connection is so limited and there is some originality and imagination, there are countless applications. Because the relativity of running memory on most tags is relatively limited, there is basically no need for higher data rate.
Most NFC tags of model specifications include 100 bytes to 1KB of running memory, although the memory space of model specifications can reach 64KB. This large amount of storage is generally used for inductive cards.
Although this storage capacity sounds limited, it allows many 8-16 bit (1-2 bytes) sensors to read values or data information of the content adhered to by related tags.
Many NFC ICs produce kinetic energy collection output, which can produce about 5mA current under good standards. The following are solutions for less than 5mA, and there is no special proposal:
Power supply system for external sensors and digital integrated circuits. In terms of temperature sensing, nfcic with embedded temperature sensors has long been widely used to track perishable goods.
The capacity of the external storage power supply system shall exceed the capacity shown by the NFC IC.
Upgrading e-ink indicates.
Charge a small lithium battery.
Charge the super capacitor (electrolytic two-layer power capacitor) battery
NFC tags, tags and basic ICs are widely used for property tracking, so they must be very cost-effective. If every product in the mall is labeled with NFC label, or every dress in the fashion store, even if each label 50c, it will quickly become less and less popular. Fortunately, the simplicity of NFC makes it easier to manufacture labels and basic labels. The cost of each label is between 10C and 50c, which actually depends on the volume.
When reading the article NFC specifications, you will find that they have been built to apply to a variety of current specifications and applications. Fortunately, due to everyone’s rationality, there is basically no popular industry. Electronic engineers in NFC implementation must master the depth of NFC label classification. All contemporary smart machines must be applicable to each label classification to comply with NFC specifications. The data analysis table will clearly indicate the role and characteristics of each nfcic, whether digital power amplifier or microwave sensor, label or reader, paper sticker or all SOC.
Type of NFC tag
The NFC specification now includes another fifth type with related nfc-v technology. The basic unit of information used in memory management is called a block. The fixed size of each block is 16 bytes. The number of memory blocks available depends on the chip hardware. Memory blocks are not directly addressable, but relative to the service to which they belong.
NFC class 1 labels that contain data conflict protection can be set to be rewritable or read-only. Their memory size ranges from 93 bytes to 2 KB (enough to accommodate URLs or other small amounts of data), and the communication speed or data rate is 106 kbit / s. The market price of type 1 label is low and does not support anti-collision mechanism.
Like the type 1 tag, the type 2 NFC tag complies with ISO / IEC 14443a, can be rewritten or read-only, and the communication speed is 106 kbit / s. However, the memory size of these tags ranges from 48 bytes to 2 kb, and anti-collision mechanism is supported.
Type 3 NFC tags have more memory and faster speed than type 1 and type 2 Tags. They comply with ISO / IEC 18092 and JIS x 6319-4 standards, but do not support encryption and authentication. The type 3 tag can be set to read-only or rewritable mode, supports anti-collision mechanism, and contains 2 kb of memory. The data rate is 212 kbit / s or 424 kbit / s.
The type 4 NFC label complies with ISO / IEC 14443. They are factory set to read-only mode and require specific service devices to update their data. They can hold up to 32 KB of memory and support data rates of 106 kbit / s, 212 kbit / s and 424 kbit / s, as well as anti-collision mechanisms.
NFC specification adopts type 5 NFC label; They comply with ISO / IEC15693 standard, contain more than 64 kb of memory, support 26.48 kbit / s data rate and anti-collision mechanism.
Application of NFC tag
The application of NFC tag is to write some information into an NFC tag. Users can immediately obtain relevant information by waving the NFC tag with an NFC mobile phone. For example, businesses can put NFC tags containing posters, promotion information and advertisements at the door of the store. Users can use NFC mobile phones to obtain relevant information according to their own needs, log in to social networks and share details or good things with friends. Although NFC tag is very convenient and low cost in application, the application prospect of NFC tag is not optimistic with the popularity of mobile network and the gradual popularity of QR code. Because compared with NFC tag / label, QR code only needs to be generated and printed into a small image, which can be said to be almost zero cost. The information provided is as rich as NFC, and it will easily replace the application of NFC tag / label.
How to make NFC tag / label
Since NFC tags can be played like this, how should they be played? First you have to prepare some information and materials.
First of all, you have to have a mobile phone that supports NFC. At present, Android supports many NFC mobile phones, such as Google’s own sons.
Secondly, you have to have NFC tags. You can buy these on a treasure. Domestic Shanzhai ones are very cheap, generally ranging from 1 to 3 yuan. Of course, cards with close communication can be used as tags, such as bus cards, meal cards, etc. of course, cards used by punch cards of some companies can also be used. However, it is strongly recommended not to use these cards, because the information on these cards may be erased during production, resulting in damage to the original information in your card and economic losses, except for the old ones.
Finally, it is recommended to use foreign software tagwrite (for erasing and writing NFC information) and NFC task launcher (for writing NFC information, there are many modes to choose). Although the software is in English, it is easy to understand. Of course, there are some software in China, which can be searched and downloaded in the market.
(2) Production process
First, open tagwrite, execute tool and erase to erase the content in the NFC tag. If there is no content in the tag, this process can be ignored.
Then, open the NFC task launcher, click NFC, and create a new task. Enter the task name of a tag in the tag name field. You can enter it at will, preferably for your own understanding, such as “test”, then click add actions, select an action, such as media, start / stop media playback, then click next, and then click Save & wire in the upper right corner, Then put the tag / label close to the mobile phone and click next. After the display is successful, the tag / label is made successfully.
Tip: when selecting actions, you can select a variety of actions. Of course, do not exceed the tag / label storage capacity. You can make several more tag / labels. Each tag / label has a specific combination, such as work tag / label, home tag / label, car tag / label, etc.
How to use NFC Tags
When the NFC function of the mobile phone is turned on, just put the mobile phone close to the tag / label, and the mobile phone automatically reads the tag / label, displays the tag / label or executes the commands in the tag / label. If the tag / label “test” is made above, the function of playing music is executed when approaching for the first time, and the function of playing music is stopped when reading the tag / label again for the second time.
China near field communication tag manufacturer www.tractility.com offers NFC tags.