Life Simplifiers in the Testing Laboratory

14 November 2024

What do a car's key fob, a photo printer in a drugstore, and a washing machine have in common? They could all be familiar with the lab of TÜV NORD High Frequency Technology in Cologne-Dellbrück. Here, Ralf Trepper, Denis Raschka, and their team test, among other things, for immunity to interference, electromagnetic compatibility, or cybersecurity.

 

In the high-frequency technology lab, you test washing machines, among other things. Why?

Denis Raschka: Every device, every car, and every machine communicates with its environment via radio today. In short, it must be ensured that the device does not interfere with other applications and cannot be disturbed by other applications. More and more manufacturers want to integrate wireless applications into their devices. Washing machines have been around for more than a hundred years. But today, these devices are supposed to be connected via Bluetooth to an app. This way, the washing machine can notify you when the washing cycle is complete. The goal is to make life easier.

Back to the different applications: Are there many laboratories that specialize in certain applications?

Ralf Trepper: In fact, there are several laboratories that offer RF testing. However, there are specialized applications that not many can test. For example, lane departure assist systems: the latest generation operates in the 76-gigahertz range. There are not many laboratories in Europe that can measure such high frequencies. The measurement technology has become very complex and demanding.

Is it difficult to adapt to ever new products, testing procedures, and requirements?

Denis Raschka: Actually, I prefer it when we get something on the table that we haven't had before, something new. Last year, for the first time, we tested certain car radios. That was a real challenge. But it's also fun because you have to think about how to design the test.

So, there's no one-size-fits-all test. Can you still say how long such tests take in your lab?

Ralf Trepper: When we talk about short-range devices, like a single-channel radio – for example, a garage door control with a transmitter and receiver – then that takes about three to four days of pure measurement time. Then there are setup times and the writing of the test report. The cycles are quick. We also have other topics that are much more complex. For example, a large device with connections, a LAN port, a serial port, and various types of radio technology. Such devices might stay with us for a few weeks.

Considering the few standard regulations, that’s quite long. What exactly is being tested?

Denis Raschka: In the area of electromagnetic compatibility (EMC), we measure the device emissions and test the device’s immunity to electromagnetic disturbances. In the radio field, for example, we measure the power, emissions, and bandwidth of the radio signal. The third pillar is the electrical safety of the devices. Next year, cybersecurity will be mandatory and must be considered for radio devices.

And what happens next?

Ralf Trepper: Looking ahead is very difficult. In hindsight, it becomes clear: Take the car key fob, a non-specific short-range device. The first ones came onto the market at the end of the 1980s. At that time, most of the radio technology was analog, and digital radio was still in its infancy. What fascinated me the most was how quickly the development advanced there. The first generation had a fixed code in the key, which was always the same. When it was then found that this was not secure, the rolling code was introduced. That was the first innovation: it changed synchronously with the car. After that, there were intelligent systems: these are essentially the keyless systems, which communicate with the car and exchange security packets. Only if these were met would the car open. So, a lot has happened. The function has remained the same, but the security aspects have changed drastically.

What other significant advancements have there been?

Ralf Trepper: Radar technology, in particular, has undergone an enormous development. In the beginning, the radar systems were very simple, and a lot has happened thanks to computing power. But especially in the cellular sector, things are moving quickly, from GSM, which is still partly active, to UMTS and 4G, all the way to the current 5G standard. These are very large steps, especially in terms of data transmission volumes. I didn’t foresee it developing so quickly and to this extent. When you think about it: it’s only been 17 years since the first smartphones came onto the market. Precisely because so much is happening, the work is so much fun. What’s interesting for us is that we get prototypes. This is where you can see where things are going and how the next step has already been taken. Otherwise, you wouldn't get to see that. Even if we don’t understand everything at first, because for us it’s also initially a black box. But through the measurements, the technology, and the conversations with the customers, we learn a lot, and that makes our work very interesting.