Why say it, when you can spray it? Researchers have been at the chemical substances again
We’ve heard all the jokes about Smellyvision, which would add smells to your TV experience, and now it looks like we’re about to hear them all over again, but this time, for the Smellyphone. Yes, we’re talking about communication via smells. And no, we’re not making it up (although we did make up ‘smellyphone’, as academics have no sense of humour).
Nariman Farsad and Andrew Eckford of York University, Toronto, Canada, and Weisi Guo of the University of Warwick in the UK, published a paper just before Christmas entitled ‘Tabletop Molecular Communication: Text Messages through Chemical Signals’.
Most modern telecoms systems rely entirely on electrical or electromagnetic signals, yet there are some niche applications were these technologies are not convenient or appropriate. For example, inside networks of tunnels, pipelines, or unpredictable underwater environments, or collecting telemetry from extremely hot places such as engines.
And a much smaller level, between micro- or nano-scaled devices (due to the constraints of the ratio of the antenna size to the wavelength of the electromagnetic signal).
So if you can’t use electromagnetic signals, then what can you use? For the answer, the researchers turned to nature. Chemical signals are used at a cellular level to convey information, and pheromones are used for long-range communication between members of the same species. In other words, they’re looking at smells.
Together, these are referred to as ‘molecular communications’, and their requirement for very little energy makes them appealing to scientists.
To test if this is indeed a viable means of commercial communications, the team implemented a macroscopic molecular communication system that transmitted a short text message using chemical signals – the first of its kind. Costing just a few hundred dollars and covering a single table top (although obviously this would be miniaturized in any real-world application), the experiment produced positive results.
The transmitter received an input text message (for the experiment, the message was “O Canada”), then converted it into a sequence of binary bits and modulated them on a chemical signal. They used an Arduino Uno open-source controller and an electronic DuroBlast spray. A simple desktop fan placed behind the spray helped assist the propagation of the chemicals to the receiver (an off the shelf sensor powered by another Arduino unit) up to 4m away.
The experiment was intentionally basic, and was designed to encourage further experimentation by other researchers. And with an optimal bit rate of 0.2 bits/second, it’s not exactly broadband! But it’s a start, and it looks like a promising area of study. As the team says in its conclusion:
“Although high transmission rates were not achieved in this work, the transmission rates can be significantly improved by using better fans, more sophisticated protocols and detection algorithms, use of multiple chemicals, use of multiple-input and multiple-output (MIMO) communication, designing better sensors, and using sensor arrays. We leave these for future study.”