Multiprotocol chips are allowing creation of IoT devices that seamlessly switch among competing connectivity channels

By Richard Quinnell, editor-in-chief

IoT
developers targeting home and building automation once needed to choose which
wireless connectivity option to implement. Wi-Fi, Zigbee, Thread, Bluetooth,
and others competed for several years to become the de facto standard for home
automation by virtue of superior market acceptance, yet none have won a
decisive victory. The advent of multi-protocol wireless SoCs may now be
resolving that conflict, but not by declaring a winner. Instead, the new
devices are allowing an armistice in which the competing wireless approaches
co-exist and interoperate without surrendering any market share.

One
reason for the long standoff has been the diversity of requirements on home
automation design. Wi-Fi has the advantage that it is already in the home
servicing computers, tablets, and streaming media devices. But for the IoT
node, the power requirements of Wi-Fi are unsupportable when battery operation
is needed. Low-power applications, instead, have turned to Zigbee or one of the
other 802.15.4 wireless protocols to maximize battery life or have opted to
use an NFC or Bluetooth connection to a smartphone. In these cases, connection
to the internet requires an additional hub device (the phone can serve as that
hub). For the devices to communicate with one another, they typically would
exchange data in the cloud rather than directly.

The
competing technologies were all trying to encourage consumers to pick them,
thereby defining a winner in the protocol wars. But consumers didn’t flock to
any one approach in droves. Confused and unwilling to risk investing in
something that could become obsolete, they mostly just held off purchasing
anything.

But
the landscape has changed in the past year with the advent of SoCs that
implement multiple wireless protocols. What began with families
of code-compatible devices
that allowed a single design to offer a
range of connectivity options quickly became single SoCs that provided several
options in the same chip
, first for gateways and then for edge-node
devices. With the ability to switch among the protocols as needed, these SoCs
have enabled the design of devices that can be configured to work within a home
automation system regardless of the protocol that the consumer has adopted.

Homey_original

Multi-protocol SoCs are enabling design
of home automation products like the Homey that can connect to several wireless
network types, allowing cooperation instead of competition among technologies. Image
source: Kickstarter.

In
the most recent example, Redpine Signals has implemented three different
wireless protocols in a module containing only one active radio. Furthermore, the
devices utilize a “big-little” architecture for their processing and wireless
connectivity, allowing rapid transitions between high-performance and low-power
operating modes. The result is a combination of low power and multiple channel
operation that allows even battery-powered edge-node devices to support a
multitude of wireless protocols essentially simultaneously.

Redpine’s
multi-protocol devices come in three flavors. The WiSeMCU RS14100 is a low-power,
enhanced-security wireless subsystem available in both SoC and module forms.
The RS9116 is available as n-Link, which provides a connectivity subsystem for designs with large host
processors running application code under Android, Linux, or Windows, and as WiSeConnect, which targets embedded
applications and provides its own MCU, allowing it to operate with smaller host
MCUs or as a standalone processor running the application code. All three
devices are equipped with a wireless transceiver capable of running dual-band
(2.4-GHz/5-GHz) Wi-Fi (802.11a/b/g/n), Bluetooth 5, and 802.15.4 wireless protocols,
which include Zigbee and Thread.

The
advent of multi-protocol radio modules is bringing an armistice to the protocol
wars in home automation. Vendors will no longer need to be concerned that their
chosen approach will get edged out of the market, and consumers will no longer
need to worry about their choices becoming obsolete. It’s a relief for all
concerned.

What
will be happening instead is that home automation devices will increasingly be
able to connect with a single hub that supports all the various wireless
protocols, and devices themselves will be start becoming able to connect via
several different protocols without suffering cost or power penalties. Instead
of needing separate networks for each connectivity type, consumers will have a
heterogeneous network that supports whatever device choices they choose to
make. Furthermore, these devices will be able to communicate directly, increasing
device responsiveness and freeing them from dependence on the cloud for their
coordination.

The
first building blocks of this multi-protocol approach are already available and
were on display at CES 2018. Both LG
Electronics and Samsung announced televisions and appliances that could serve
as hubs for home automation systems. The Open Connectivity Forum was demonstrating
the middleware that allows home automation devices using different protocols to
interoperate through such hubs.

Personal
voice assistants were also on display that could serve as a multi-protocol hub
for home automation. Chipmaker Qorvo, in conjunction with device maker
Humax
, announced the creation of a voice assistant that links Zigbee and
Thread networks to the device and through it to the cloud. European device
maker Athom also had a multi-protocol voice assistant on display: its Homey platform. This device bridges six major home automation
wireless channels, including Wi-Fi, Zigbee, Z-Wave, and even infrared.

The diversity in wireless protocol options will
remain in place for some time to come because each offering addresses a
different set of needs. But the competition among them to become the dominant
technology should ease considerably with their newfound ability to work
together rather than in isolation. The protocol wars are not quite over, but at
least there is a ceasefire in place, allowing both developers and consumers to embrace the options that they prefer without risk of being on a losing side.