How a virtual antenna solves IoT problems

  • November 27, 2020
  • Steve Rogerson

Jaap Groot, CEO of Fractus Antennas, explains to IMC executive editor Steve Rogerson why his company is one of the latest to become an IMC sustaining member.

A not uncommon approach to IoT device design is to leave the antenna till last and then find somewhere on the PCB to stick it and almost hope for the best. The result is often anything but the best and can cause many problems with devices in the field failing to make a sustainable connection to the network.

But what about instead using the PCB itself as the antenna, adding a booster and a few components to tune it to whatever flavour of IoT being used, such as LoRa, Sigfox, NB-IoT, wifi, 5G and so on? That is the idea behind the virtual antenna technology from Spanish company Fractus Antennas, one of the latest firms to join the IoT M2M Council (IMC) as a sustaining member.

Jaap Groot

I caught up with its chief executive officer Jaap Groot to find out more about this exciting technology.

“We don’t sell antennas,” he said. “We sell boosters. We have shipped nearly ten million. We use the PCB as the antenna. The signal is weak, which is why we have a booster.”

To match to the network signal, a few components are needed between the radio and the booster. These are quite cheap components, maybe between two and eight depending on how many bands need to be connected.

Normally, he said, people choose a processor and radio, and then squeeze in the antenna.

“This is not optimised for the radio side,” he said. “Only a fraction of devices have an optimal radio, so you can’t get the power to make the connections and the range can be smaller. This can be crucial for, say, smart meters as they can be underground and in buildings.”

Groot believes his company’s virtual antenna will become dominant in IoT edge and multi-radio access devices. He expects to hit the ten million shipment milestone early next year but still sees the company as a small player.

“We need to scale up,” he said. “I have been to several IMC meetings. About two years ago, we started participating in more events. Joining means we can reach a huge audience through webinars and so on. For a small company, we can’t be effective at many events with a little booth, so being part of the IMC helps.”

Going forward, Groot is careful about making forecasts and is critical of companies such as Sigfox, which he says have hyped the market too much.

“It doesn’t help,” he said. “Sigfox is doing a lot of harm by being too optimistic and pushing the market in the wrong direction. On the LoRa side, I think Semtech is on the right track.”

Groot worked for Sigfox from 2013 to 2015 and for Semtech from 2015 to 2020 before joining Fractus Antennas.

As to NB-IoT, he described this as a “nightmare” for some people, saying: “It is unstable and doesn’t work properly.”

He said the beauty of NB-IoT was its coverage, but only in some countries. In others, it only covers half the country and further expansion won’t happen until more revenue comes in.

“The most painful side though is power management,” he said. “This is unstable.”

This year has been unusual. And Groot believes some of the changes that have happened because of Covid-19 are here to stay.

“The way of doing business has changed, probably forever,” he said. “Working from home will become more common.”

He said there had also been a shift in the way smart buildings were designed with occupancy control and social distancing now key factors. He also said that within smart buildings more information was being processed at the edge rather than in the cloud. He gave as an example a toilet.

A door sensor monitors every time someone goes in. After fifty people have used the toilet, an alert is sent to the cleaners. What has changed is that the sensor does not send an alert to the cloud every time the door opens, but counts the openings itself and sends the alert when it reaches fifty.

“A lot of stuff will move to the edge because communications is expensive,” he said. “Energy harvesting will also become more important.”

He also believes that multi-radio devices will become more common so the same device can be designed to work with LoRa, Sigfox or whatever.

“That is fine on the network side,” he said. “On the edge though, it would be good if I could buy a sensor that could connect to any network. I can see a future for multi-radio devices. For a device maker, there could be huge savings in cost.”

One way to do this would be to use a virtual antenna, and Groot knows just to place to get one.