Audio in embedded systems

Anders starts from the fundamentals once again: “On the lowest level we have an electronics engineer drawing the signal paths on a circuit board, ensuring signal integrity at all stages.” He goes on by telling how analog filtering must be applied when microphone input is fed to the AD and microprocessor. Now we are getting close to Anders’ core competence. “C is the preferred language for embedded software. But a DSP, for example, may have instructions that you can’t address from C. Then you have to program at a lower level to call those functions.”

You can’t meet the requirements for compactness and energy efficiency with just careful programming and planning of the circuit boards. “We prefer to work with chips from STMicroelectronics, they have good platforms for this kind of systems.” An important competence is to know the component market and choose the right chip. That enables you to implement the device with a minimum of components, and save both space, weight and energy.

The final step is often software for the computer, which nowadays is a common companion for devices. Yes, that’s an important component too, but Anders doesn’t mind if someone else handles that. It’s apparent that he thrives closer to the hardware, where the real processing is done.

There’s plenty left to invent

It’s easy to become enthusiastic when discussing the potential of digital technology with Anders. Listening to streamed music, always and everywhere, is perhaps what most of us think about when you say audio technology. But the possibilities are wider than that, far wider. The audio devices are becoming even smaller and will soon be integrated in our clothes. Earbuds support performing artists and technology can improve wellbeing significantly for hearing impaired people. Internet enables us to transfer sound anywhere in the world and perform more advanced processing in datacenters.

We are used to access the net from gadgets with an operating system, like computers or phones. But Anders reminds as that there are lighter solutions as well. You only need hardware for 4G/5G or WiFi, and the rest is relatively simple programming. That makes it easy to exchange data with a server, either sound or other kinds of information. This opens breathtaking possibilities for new applications. A server could for example analyze audio from elderlies’ apartments and use smart algorithms to detect accidents. Or even understand spoken words and commands, to alert the relatives.

Maybe you remember those communicator badges that the Star Trek crew used? A light touch and they had voice contact with each other. When talking to Anders you get a strong feeling, that things like this are just waiting to be implemented.

The last question is what Anders would do if he had free hands, and unlimited budget, to create something cool and audio-related. He thinks for a while and starts: “I’m very interested in noise-cancellation. Is it possible to create silent zones without solid walls or other acoustic constructions?” That’s a brilliant idea as it hits one of our big problems spot on. Our soundscape is often too complex and distracting. We are used to control what music we listen to, but it would be equally important to be able to eliminate what we don’t want to hear.