In one of the previous blogs “ If data is the hero , is device a super hero “ I had shared the need to provide device and the device health monitoring due importance as we aggregate data and work on them to whip up insights .
The network characteristics of IoT as based on wireless technologies are quite different from those for traditional wired or wireless networks because the number of devices participating in communication is very large. In addition, traffic per IoT device is typically not so much because each IoT device senses and transfers a small amount of data to a corresponding IoT server. Although data generated from a huge number of objects may collectively have some impacts on the network performance. Furthermore, IoT networks should operate stably and sustain-ably for a longer period without any need for human intervention
Somewhere in the euphoria , of IoT and the change agent it promises to be, did we forget that we have to provide power these constrained devices ( sensors ) ?
All our life we have looked forward to power and performance, be it our music system or the automobile ; power is something we seek in products ( or things ) .
Although the backbone architecture of networks hog the limelight in a typical IoT program , the actual driver to a successful deployment of the network hinges on the devices at the edge . This “edge effect” is amplified given the numbers and the challenge is exacerbated when the connectivity and computing being wireless in nature. Just imagine if these have to be kept charged , imagine the form factor of the devices and the energy bills to the boot .
So these “edge devices “ or the “IoT end points” need to be
- extremely inexpensive ,
- with minimal form factor
- with low or no demands for power ,
- and the need to be autonomous (untouched by human command)
The ideal situation would be to make these edge devices run of any sort of electricity ( or provide access to foraged electrical energy from heat , motion , light that could be converted to electrical energy.
So the device should have the capability to may be work for a decade powered by a small battery and / or through the energy foraged from the ambience it is operating in as mentioned above
Here the aggressive R&D on Low Power or No Power devices ( LO-NO-PO) makes a grand entry to smartly address this conundrum.
Let me go back to high school chapter of electrical energy .Power consumption as we have learnt is the square of Voltage ( P=V^2/R, where R is the resistance a constant ) .When the operating voltage decreases the corresponding power consumed drops and so also the performance. While this may adversely impact ones music system , but this is what is required precisely for an “edge device”.
Exploiting this has led to the emergence of “sub-threshold “processing. This technique allows the microcontroller to run from a voltage supply lower than the transistor’s switching voltage.The solution which is being perfected is Sub Threshold Power Optimised Technology ( SPOT) which has been pioneered by companies like Ambiq and Minima aided by university led academic research .
While these products are getting ready to come to mainstream , they are addressing some of the the challenges of making the devices less sensitive to factors like temperature , noise and other environmental factors .
Will this extreme energy efficiency lead us to a battery-less future ? May be we will be seeing that sooner than later !!