When I was a kid, we had an example of the very latest high technology electronics in our kitchen: a transistor radio. This amazing device was light and portable, ran for ages on a set of batteries and would come to life instantly when switched on, offering a choice of sources of entertainment from around the world. I seem to recall that it used an incredible seven transistors to achieve this feat. The 1960s was a time when anything seemed possible.
My grandmother, on the other hand, did not have any time for such new-fangled gadgets, which she [quite rightly] thought sounded tinny and were not conducive to relaxed listening. She enjoyed the radio and, in the corner of her kitchen, was her pride an joy: 1940s technology at its best – her “wireless”. It is interesting to reflect that now, nearly 50 years on, we are still using this term …
The meaning of the word “wireless” is clearly “without wires”. This is odd, as there was never a widely used wired entertainment system that the wireless radio receiver replaced. Nowadays, we actually use the term more accurately to describe devices that replace hitherto tethered equipment. It is amazing to see how ubiquitous such technology has become, which can be illustrated by looking at what is to be found in my immediate surroundings as I write:
- The keyboard and mouse are wirelessly connected to the computer [unknown radio technology].
- The computer uses WiFi to connect to the router.
- My iPad uses WiFi too.
- My cellphone is GSM, but that also has WiFi.
- There is a DECT cordless phone system.
- I have a Sonos audio system – the boxes talk to one another wirelessly [unknown radio technology].
On my desk is the base station for a FitBit [not mine, of course – it has gone off to work with its owner], which is plaintively calling wirelessly to receive updated data [unknown radio technology].
So, I am swamped in radio waves. Surprisingly, I do not use Bluetooth, which is a wireless technology that many people would name straight away. This reflection made me wonder what the overall picture is of wireless technologies being used in embedded designs.
So, I took a look at the UBM Electronics Embedded Market Study for 2011. This suggested that nearly 40% of designs are including some wireless technology. Of the technologies used, WiFi is dominant, with Bluetooth coming in second, followed by cellular and Zigbee. My feeling is that cellular is used almost exclusively by cellphone handsets and infrastructure and is obviously intrinsic to their operation, which makes their use of wireless less interesting. I guess this means that about a third of other embedded devices now have some wireless capability, which sounds about right to me.
I am curious about what “unknown” wireless technologies are employed by some of my devices listed above. I would be interested in any insights by email or comment.