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■ FIGURE 2. The Telit Wireless Solutions HE910 module
supports the HSPA+ 3G wireless standard but can fall back
to slower GSM/GPRS/EDGE if needed. It covers five of the
most popular cellular bands.
small or inexpensive it may be. The computers make the
M2M automatic. While the pure definition of M2M is
strictly machine-to-machine, it can also be thought of as
machine-to-human or human-to-machine. The main
common element is remote monitoring, control, or access.
One subtle example is the embedded cell phone in your
Kindle or iPad e-reader that can access a remote data
base and download a book. Or, what about GM’s OnStar
system in Chevys, Buicks, and Cadillacs? It has a built-in
cell phone that can be used to alert the system of an
accident or break-in. Or, it can open your doors remotely
if you lock your keys in or lose them. The remote
monitoring and control of Predator drones can be
considered a form of M2M.
M2M has many current uses and lots of potential. The
health care industry is beginning to adopt it for in-hospital
as well as remote patient monitoring. Transportation
applications are big now especially for vehicle tracking.
Each car or truck in a fleet contains a GPS satellite
navigation receiver that sends the location via an M2M
connection to a remote monitoring point. Look for more
of that, as well as some yet to be identified uses.
Home monitoring and control is another growing
application area. With M2M, you can monitor and control
the home environment and implement energy-saving
procedures. You can monitor and control appliances,
security systems, and alternative energy sources like solar
panels. The connection of a smart electric from the utility
lets the electricity or gas usage be monitored by M2M.
M2M is beginning to play an even larger role in the smart
grid, with the growing use of communications and
computers to better monitor and control energy usage for
cost savings and pollution mitigation.
What makes M2M so simple to do is all the available
wireless products that are easily adapted to the myriad of
tasks. Today, cellular radios dominate the M2M landscape
but Wi-Fi, ZigBee, and other popular technologies can be
used. With cell phone usage nearing saturation, the
cellular carriers are looking for new revenue from their
networks. The smartphone revolution is providing some
room for growth from data plans that feature more video
and less texting and email. However, M2M is an untapped
■ FIGURE 3. The B&B Electronics Wi-Fi system for M2M
applications is designed for industrial monitoring and
control applications. The Access Point accepts inputs from
the embedded modules on the lower right. The
application communicates back to the control point via an
source of growth. Most of the big carriers like AT&T,
Sprint, T-Mobile, and Verizon are building M2M services.
Since most M2M applications have a low data rate,
existing GSM/GPRS/EDGE and cdma2000 networks are
adequate. The newest 3G and 4G cellular networks can
provide even faster M2M data services.
Figure 1 shows a typical cellular transceiver that can
be built into almost any other product. This is Sierra
Wireless’ SL6087 module that supports the 2G
GSM/GPRS cellular standard. It can interface to almost
any sensor or actuator (light, relay, solenoid, motor, etc.).
Its ARM9 embedded controller with the appropriate
software implements an M2M node that connects to
some remote computer through the existing cellular
system. Figure 2 shows a 3G module. This one from Telit
Wireless Solutions uses HSPA+ 3G technology, and works
in the five most popular cellular bands. HSPA+ can
achieve data rates up to 21 and 42 Mbps. It is also
In some cases, the sensor or actuator may be
connected to a Wi-Fi public hot spot or other access point
that, in turn, provides connection to the remote computer
via an Ethernet network. Some systems use an
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