Intelligent and Connected: Wireless is key to the IoT

Irrespective of the research firm numbers or the predictions from any of the large companies with a vested interest in the growth in devices, we are all pretty much agreed that there will be billions of things connected to the Internet over the next 5 years or so. Some of them will be wired – there will be industrial automation sensors and actuators that have always been wired and they will continue to be so, if the wiring infrastructure is deployed as a matter of course during the commissioning of the factory or processing plant. However, everyone is looking to reduce costs and complexity and wiring buildings is costly and you need to have predicted every scenario otherwise the wires will be in the wrong place or not there at all. This is where wireless comes into its own.

Adding a radio to any device enables its connectivity whilst retaining its mobility – the ability to place it exactly where needed and move it in the future if required. The challenge is that, as any embedded system designer will tell you, radios suck power. Consequently, there is a concerted effort going on in the industry to reduce the power drain from the radio so that the device can be placed in situ, worn or transported and not have to be recharged or have the battery replaced for the life of its use. So let’s have a look at the application spaces for  wireless objects in relation to us as humans and our environment.

In the Personal Area Network (PAN) space, there have been a few contenders with marginal traction – ANT being a case in point – but it  has been the inclusion of Bluetooth 4.0/Bluetooth Low Energy (BLE) in all new smartphones that is driving the use of BLE for everything that may be connected in and around your person. You only have to look at the burgeoning wearables space to see that BLE has become and will be the dominant connectivity option  for short range use. The massive volumes will bring costs down and the increase in the number of developers familiar with using BLE will see its use expand into M2M connectivity when the distance between objects is small.

If we look at the Local Area Network (LAN) space, we see a well established shift into Wireless LAN (WLAN) due to the massive adoption of WiFi or more precisely, 802.11a/b/g/n/ac, in laptops, phones and tablets – to the extent that, as a product designer for the consumer, you would expect there to be a WLAN gateway/router in every home. There is an expectation of ubiquity for WiFi and it will continue to connect devices with high bandwidth needs such as cameras, televisions and consumer electronics. The drawback is that the 802.11 protocols are very “chatty” and so power consumption is an issue and you would avoid using WiFi for unattended devices that need to be in Field for years at a time. For low power WLAN connectivity, there is a trend towards the use of 802.15.4 radios such as Zigbee or Zwave but the take-up is not on a par with WiFi. The push towards the use of 6LoWPAN for in-building device connectivity has the potential for defragmenting the low power WLAN space and creating critical mass for huge growth.

The real challenge for the IoT is when you leave the relative confines of a building or campus and you want to connect things over large distances (greater than a kilometre). You are now in the world of cellular (2G/3G/4G), satellite or proprietary sub-gigahertz networks.

The main challenges here are cost and power consumption. The Mobile Network Operators are getting pretty creative with their service offerings for Machine-2-Machine (M2M) to reduce the operational cost of connecting tens of thousands of devices but a lot of the applications require the device to be in operation for 10 years or more and that is very difficult (nigh on impossible) to achieve using cellular networks.

So the IoT world is in need of  a radio with the cost model and power consumption of BLE but with the range of cellular. I recognised this a few years ago and is why ARM is a founder member and promoter of the Weightless SIG, setup to define an open standard for a new type of cellular network designed specifically for M2M. Since then, there have emerged a few other companies with technology that promises a similar capability – sub–$2 transceivers that can connect over 10km and last 10 years on a single cell whilst also costing single digit dollars per year to operate.

Wireless connectivity is and will play a crucial role in the explosion of the Internet of Things for all the reasons we have looked at above. Some are already well established, like WiFi, and are an automatic choice for many applications whereas others are still in early stage and will require some critical mass before taking off in any significant way. It is certainly a very interesting time for the wireless industry and the world around will be increasingly reliant on radios to simplify our lives, increase productivity and make more efficient use of our scarce natural resources.