Cooking up a connected product
Connected devices tend to
sit at the more complex end
of the embedded system
spectrum, irrespective of whether they
gather sensor data by themselves or
interface with pre-existing equipment.
Their complexity arises from
the interaction between their three
constituent parts: the local part,
which generates the data or needs
some control; the far system which
records the data and/or provides
instructions; and the connection
between them, which typically
operates over a large distance
and is often observable (and even
interruptible) by untrustworthy third
parties.
These complexities are, however,
often outweighed by the improved
customer engagement, detailed
business insights, and even entirely
new commercial models that can be
achieved.
The ne balance between
complexity and function means that
building the right kind of connected
device is often part art, part science.
In fact, it’s a lot like cooking a
great meal – there are practically
an in nite number of ways to bring
key ingredients and dishes together.
Some of which can be assembled
quite quickly, whereas others will
take more time and effort to perfect,
but which may be better suited to
someone’s tastes.
One approach is to break the IoT
development process into several
Adding a connected device to your portfolio can be challenging.
Jonathan Pallant looks at how to pick the ‘perfect ingredients’
(like a mobile phone) and a larger,
higher-power gateway (like a Wi-Fi
router). You also need to consider
the ownership and reliability of those
gateways, comparing for example
a homeowner’s Wi-Fi router versus
accessing a mobile network.
Whichever way you go, it is almost
always better to rely on existing
connectivity standards with broad
market acceptance rather than
developing something from scratch.
The Chipset Course
The rst decision to make is whether
to opt for a chipset that integrates
processor, memory and radio,
or whether to combine several
ingredients to get the right mix
of performance, price and power
consumption.
If you need low-power cellular
speci c but fundamentally connected
choices. But it isn’t always easy to
work out which decisions to take rst,
and there is always a risk that an
early decision could restrict your later
choices and lead to the whole system
being sub-optimal.
We’ve alliteratively grouped these
choices into six different areas to
consider when planning the perfect
IoT ‘feast’.
Connectivity is probably the best
place to start, as it’s the fundamental
component that the rest of the
offering hangs around. The main
course, if you will.
The Connectivity Course
The key connectivity technology
requirements for products are de ned
by cost, power consumption, range,
data rate, and latency. But they are
ultimately tied together by the Laws
of Physics and Economics. And all
of today’s technologies exist in their
own particular sweet-spot within this
multi-dimensional space.
Most systems will probably need
wireless connectivity to access the
Internet, which sadly is typically
less reliable and higher cost than
using a wired connection. Almost
all wireless standards involve at
least two classes of device – a
smaller, lower-power component
Below: There are
few absolutes in
technology. There will
always be a range
of potential solutions
available
18 9 March 2021 www.newelectronics.co.uk
/www.newelectronics.co.uk