Everything you need to know about RFID

Although radio wave technology for object identification has been around for several decades, the boom for this solution has only recently begun. Nobody disputes that the remote radio identification system is an interesting alternative to common barcodes. Some automotive and retail giants have already fully trusted RFID.

Hertz's Legacy

Searching for the forefathers of radio identification, we must go back quite a bit in time. It all started in 1886, thanks to the determination of a well-known physics professor. Heinrich Hertz constructed an electric oscillator and generated electromagnetic waves. This significant event laid the foundations for the dynamic development of many areas of life. Less than twenty years later, a German inventor, Christian Hulsmeyer, used his senior colleague's research to develop a system for preventing ship collisions.

It is mistakenly believed that the development of technology occurred only during World War II. In the 1920s, Robert Watson-Watt, a radio physics specialist, was working on a way to track storms using a radio signal emitted by lightning. However, the truth is that the military potential of this project was noticed, which led to the field's flourishing. The first radar system was developed in the UK in the mid-30s. In the 40s, improvements in technology were worked on in many countries, focusing mainly on its military applications. 

Post-war development

Many outstanding engineers and scientists contributed to the development of the radio identification system at that time. However, let's leave the war topic, as the visible turn towards the commercial use of radio waves only came about in the 70s. Charles Walton is often referred to as a pioneer of the industry. Among his many patents, his most recognizable invention turned out to be a radio transponder replacing a door key. Many contributed to the development of RFID technology at the time, but particular credit should be given to Mario Cardullo. He patented a passive tag that not only allows reading, but also writing with radio waves.

In the late 70s and early 80s, experiments began in the US and Europe with radio toll collection for highways. RFID tags also found their place in the industrial railway at this time. In the 90s, the technology was boldly used in tourism, especially on ski slopes as part of skipasses. Although the system's popularity grew, these were still technologies working in separate standards, without any mutual compatibility. The real revolution came thanks to EPCGlobal, an organization striving, among other things, for the global standardization of RFID communication protocols. The first step towards global standardization was taken in 2005. Since then, a long journey has been undertaken, which results in the visible boom for this technology today.

RFID - how does it work?

The basic tool is an RFID reader, which looks no different from the well-known data collectors equipped with classic scanning modules. There are mobile and stationary models, for example, in the form of gates on production lines. Printed labels with barcodes are replaced by 'tags' - markers consisting of a simple integrated circuit and antenna. Like barcodes, tags are attached to the object to be identified. Radio tags differ from each other not only in construction, but - depending on the needs - also in size and protective coating. It can be, for example, an envelope or foil.

The basic function of the reader is to generate an energy field wave, which activates the tag's integrated circuit. In less time than it takes to blink, the activated tag sends a return message to the scanning device, equipped with a receiver. At this point, a game changer appears, which made many significant companies turn their attention to this solution. While each barcode has to be individually scanned, the RFID reader automatically reads up to hundreds of tags at the same time. But that's not all, because this technology provides many more advantages.

More possibilities

The simple, common tags mentioned earlier are called 'passive'. Their role ends in emitting a return signal to the reader when they receive the appropriate pulse. The antenna receives the wave, and the decoder decrypts it. Durability estimated at 20 years and high reliability are the advantages of passive tags. However, there are electronic labels on the market with much more capabilities. We call them 'semi-passive' and 'active'. The former are additionally equipped with a battery, significantly increasing their range. Thanks to internal power, they can have additional memory and sensors. The latter are the most advanced integrated circuits. Active tags reach a range of over 90 meters and have an alternative power source. They have the broadest information capabilities, but they are also the largest.

Electronic labels can also be divided according to the frequency they support. Low frequencies often occur in agricultural industries. High frequencies are used in urban transport cards. Ultra high frequencies are suitable for logistics and courier transport. Frequencies mainly differ in range and signal speed. Water and metal, former enemies of radio waves, are also becoming less and less of a problem.

RFID hits home

We've already mentioned one fundamental advantage of RFID technology over traditional barcodes. It significantly shortens the duration of many time-consuming processes, such as inventory management. The efficient, simultaneous reading of multiple tags, the lack of a need for physical visibility of the marker, and the automation of the whole process contribute to minimizing losses caused by errors. Financial savings, therefore, result not only from reducing mistakes but also from utilizing employees' time in a more effective way. Radio tags are also more resistant to damage and dirt than traditional codes, making them a good alternative in places exposed to extreme conditions.

Radio identification technology is successfully used in everyday life. We can encounter it during mass events, in self-service stores, in guarded car parks, and in time measurement during sports competitions. We will stumble upon RFID wristbands in water parks. Sometimes the technology is used to identify patients and in libraries to find books. Solutions based on RFID are increasingly appearing in the construction, restaurant, and automotive industries. They effectively enable the identification of drivers and containers in the municipal industry. They reduce theft, facilitate the registration of borrowed tools in workshops, and the localization of materials. In some countries, radio tags are implanted in pets so they can be easily identified when they get lost.

Many entrepreneurs use RFID to separate employees from machines, production lines, or rooms to which they do not have access. The system also allows for the identification of people moving around the building or the registration of working time. This increases the level of security and efficient control. RFID works extremely well in logistics. It supports the process of monitoring loads and their identification, as well as informing about upcoming technical inspections.

RFID in Poland

In our country, there are already attempts to properly use the technology. Some retail chains have started to experimentally change barcodes to RFID tags in sales and warehouse spaces. Thanks to appropriate solutions, the customer service time is shortened, and this is accompanied by better results and lower inventory losses. In Poland, radio identification is also used in some transshipment centers. The technology has automated processes related to deliveries and receipt of goods, preventing delays.

For several years, automotive companies have been benefiting from RFID, for example, within assembly lines. There are already manufacturers who strive to use the technology throughout the entire production process. The tag can remain in the vehicle from the production stage to delivery to the customer. The tag is programmed in such a way that it contains key information about the car: its paint or equipment version. It is worth noting that special tags are already being used due to the presence of metal. An improved version even uses direct contact between the vehicle and the tag - it improves the quality of transmission, treating the body as an extended antenna. 

What next?

What does the future hold for radio identification technology? Devices for self-printing and encoding RFID tags are already available on the market. Companies do not have to depend on external suppliers. Finally, let's mention a certain cybernetics professor from Great Britain. Kevin Warwick implanted a transmitter in his skin. The computer network in his laboratory recognizes the signal from the device, allowing for specific actions to be taken. Newspapers dubbed him "the first cyborg". Certainly, many unusual ideas and inventions still lie ahead for radio technology.