Long-range Personal Mesh

I have recently stumbled upon goTenna. It is a great concept for off-grid peer-to-peer communications, but as other similar inventions, will likely die in its current form.

The way goTenna works is there are goTenna Mesh "dongles" that pair with phones over Bluetooth LE and the dongles talk to each other forming a mesh network using proprietary sub-GHz radios. That allows groups maintain communication among the members, as long as there is a "path" between any two, meaning the single-hop distance is not more than a mile or so.

The problem with this approach is that you need a physical goTenna device. I imaging only few people on the planet have them. What if every phone had that built-in already?

This was the dilemma I was facing back in 2012-2013 when looking for a next generation mesh networking technology. I knew phone integration was a must. So how likely was it to convince the mobile phone vendors to include yet another radio? Chances were close to zero. Companies today are removing 3.5mm headphone jacks to save board space and free a bit more surface for antennas. So persuading them to include another radio chip and another antenna was a no-go.

So I looked at what was already in a phone wondering how to make use of what was available. It turned out we could use a Bluetooth 4 chip present in every phone to run mesh networking stack. This is how Bluetooth Mesh was born.

At the same time there was a number of companies working on new modulation schemes for Bluetooth. That work materialized several years later as Bluetooth 5 Long-Range feature, based on the so-called Coded PHY. Coded is in a nutshell a collection of modulation and error correction techniques that trade transmission speed for increased range. Our friends from Nordic Semiconductor have a good blog explaining how that works. Combined with potential to increase power output from +10 to +20dBm, Bluetooth Long Range is practically capable of reaching a 1 mile range in typical implementations. That is a pretty powerful Bluetooth, isn't it?

Bluetooth 5 chipsets are gradually replacing the Bluetooth 4 generation in mobile phones. In a not too distant future we can safely assume all phones will be Bluetooth 5 - capable, with the Long Range feature at disposal.

Combined that with Bluetooth Mesh that will be able to use the Long Range feature and suddenly you have opened exciting new possibilities for applications. Imagine WhatsApp or Messenger IM being able to use that Long Range Mesh feature No need for acwkard dongles. No need for special apps. Just continue using instant messaging with your peers even if the entire group has moved outside of network coverage. Or if the network went out of service as a result of a natural disaster like a hurricane strike.

Call to action. I think it is time for OTT messaging companies to look seriously into this development. I think it is a great use case for Bluetooth and Mesh outside the "traditional IoT" applications we have been focused on so far.

Bluetooth has incredible growth potential (measured as the number of variety of use cases). This potential is realized by the continuous effort to make Bluetooth better. Every year, every month, every day.