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Comparison of Wireless Technologies (Bluetooth, WiFi, BLE, Zigbee, Z-Wave, 6LoWPAN, NFC, WiFi Direct, GSM, LTE, LoRa, NB-IoT, and LTE-M) PREDICTABLE DESIGNS

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Comparison of Wireless Technologies (Bluetooth, WiFi,
BLE, Zigbee, Z-Wave, 6LoWPAN, NFC, WiFi Direct, GSM,
LTE, LoRa, NB-IoT, and LTE-M)
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Technical Dif culty Rating: 6 out of 10
Deciding what type of wireless technology your new product should use can be
an overwhelming task. Not only are there a huge number of wireless
technologies currently available, but it’s also a moving target with new
technologies regularly being introduced.
To help simplify the process of selecting the best wireless tech for your product
I’ve organized the various wireless technologies into a groups based on
functionality, data speed, and operating range.
Based on the intended functionality of your product, it should be relatively
simple for you to immediately determine which group of technologies you need
to consider.
For example, if you require two devices separated by 30 feet to transfer low
amounts of data then it doesn’t make sense to use any of the long-distance or
high-speed wireless technologies.
That being said, I recommend that you read this entire article regardless of your
product’s speci c needs because you can gain a general understanding of all the
wireless technologies available to you.
NOTE: This is a long, very detailed article so here's a free PDF version of it for
easy reading and future reference. You will also get an Excel spreadsheet
comparing the various wireless technologies.
Peer-to-Peer Technologies
Peer-to peer simply means when two devices are connected together for direct
communication. Only two devices can normally participate in a peer-to-peer
connection.
In the next section I’ll discuss what are called mesh network technologies which
allow many devices to all be interconnected.
Bluetooth Classic
The best known peer-to-peer wireless technology is Bluetooth. When you
connect your phone to a Bluetooth speaker that is a peer-to-peer wireless
connection between your phone and the speaker.
Bluetooth dominates peer-to-peer streaming audio applications such as this Bluetooth
headset.
Because of the relatively short operating range, Bluetooth is fairly low power. It
consumes much less power than WiFi, and a lot less than cellular technologies,
but still signi cantly more than technologies such as Bluetooth Low-Energy or
Zigbee.
WiFi Direct
Everyone knows about WiFi, but few people have heard of WiFi Direct. This is
true even though nearly all phones and tablets support it. Like Bluetooth, but
unlike traditional WiFi, WiFi Direct is a peer-to-peer wireless technology.
As you probably already know, traditional WiFi sets up an access point that
allows many devices to connect to it. But what if you want to transfer data
directly from one device to another without the overhead of an access point?
That is where WiFi Direct comes into play.
WiFi Direct uses the same basic technology as traditional WiFi. It uses the same
frequency and offers similar bandwidth and speed. But, it doesn’t require an
access point, allowing two devices to have a direct connection similar to
Bluetooth.
The advantage of WiFi Direct over Bluetooth is mainly faster transfer speeds. In
fact, WiFi Direct is over a hundred times faster than Bluetooth. That speed
comes at a price though and that price is mainly higher power consumption.
Near-Field Communication
Near eld communication (NFC) is fundamentally different than the other
wireless technologies discussed in this article. NFC communicates using
electromagnetic elds shared between two coils, whereas all other wireless
technologies emit radio waves.
Because NFC communicates via two coils that are electromagnetically coupled
together, the operating range is only about an inch or two. The two coupled coils
essentially form a transformer with an air core.
The most common use for NFC is in contactless payment systems. Although
payment data is of course encrypted, the extremely short operating range of
NFC also helps to eliminate the possibility of someone else nearby hacking the
transaction.
NFC allows the use of passive NFC tags. In this case passive means there is no
power source. Instead, a passive tag is powered from the electromagnetic eld of
an NFC reader device. Both communication and power transfer are occurring
between the two coupled coils.
The advantage of passive tags is they are simple, cheap, small, and last almost
inde nitely since there is no battery. Active tags are also available which include
a battery.
As a side note, wireless charging, where you recharge a device by placing it on a
charging mat, also takes advantage of this same phenomenon of power transfer
between two coupled coils.
Low-power / Short-range / Low-data Mesh
Technologies
There are four common technologies for creating a low-power, low-data
network: Bluetooth Low-Energy, Zigbee, Z-Wave, and 6LoWPAN.
If your product is battery operated, and needs to send relatively low amounts of
data a short distance away, then one of these four technologies is likely the best
solution.
A critical feature supported by all four of these technologies is called a mesh
network, sometimes referred to as a many-to-many network.
A mesh network allows many-to-many communication.
Normally, to send data from device A to device C you must form a direct link
between device A and device C. This is the case for peer-to-peer technologies
such as Bluetooth and WiFi Direct.
But with mesh networking you can instead send data from device A to device C
via device B. The data is sent from device A to device B, which then relays the
data to device C. This allows you to create a huge network of interconnected
devices that can cover a large area with extremely low amounts of power.
For example, imagine that you have 26 devices labeled A through Z, which are
spaced out in a line with one hundred feet between each device. Normally, if you
wanted to send data from device A all the way to device Z located 2,500 feet
away, you would need a transmitter with considerable power. This requires a
product with a large battery.
But with mesh networking, you can relay the data from device A to device B, to
device C, and so on all the way to device Z. No single device has to transmit the
data more than a hundred feet, so the power required by each device is much
smaller.
Mesh networking can open up a lot of really interesting applications.
Bluetooth Low-Energy (BLE)
Bluetooth Low-Energy is much more than just a low-energy version of Bluetooth
Classic. In fact, it’s applications are completely different than for normal
Bluetooth.
Bluetooth LE is probably the most common type of wireless functionality for the
products I help develop. It is designed to transmit/receive small amounts of data
on a fairly infrequent basis, all while consuming extremely low amounts of power.
BLE has many applications but one of the most common is transmitting sensor
data. A sensor device that measures the temperature once per minute, or a GPS
device that records and transmits its location every 10 minutes, are a few
examples.
In many cases, Bluetooth LE products are powered only from a small coin cell
battery. If data is only sent infrequently, a BLE device running from a coin cell
battery may have a battery life of a year or longer.
Bluetooth LE is widely supported by mobile phones and tablets making it an ideal
solution for interfacing your product to a mobile app. It also supports a decent
transfer speed of up to 1Mbps (classic Bluetooth can do up to 2-3 Mbps).
As with all of the technologies discussed in this section, BLE supports mesh
networking. In fact, it allows mesh networks with up to 32,767 devices!
Unless you have a solid reason for choosing one of the other technologies I
discuss in this section (Zigbee, Z-Wave, and 6LoWPAN), I highly suggest that you
use Bluetooth LE. It’s the easiest wireless technology to implement, consumes
very little power, and is the most widely supported.
BLE, Zigbee, Z-Wave, and 6LoWPAN are all potential solutions for smart home
applications.
Zigbee
Zigbee is another short-range, networking technology similar in many ways to
Bluetooth LE with similar applications. It uses the same 2.4 GHz carrier
frequency, consumes very little power, operates over a similar range, and offers
mesh networking.
In fact, a Zigbee mesh network can include up to 65,000 devices which is twice as
many as Bluetooth LE can support. However, I have yet to see an application that
pushes either limit.
Zigbee is primarily used for home automation applications such as smart lighting,
smart thermostats, and home energy monitoring. It is also commonly used in
industrial automation, smart meters, and security systems.
Z-Wave
Z-Wave is a proprietary wireless technology (acquired by Silicon Labs in 2018)
that primarily competes with Zigbee and BLE in the home automation market.
Unlike BLE and Zigbee, which use the popular 2.4 GHz band, Z-Wave instead
uses a sub-1GHz band. The exact band varies across many countries which can
cause complications if you wish to sell your product globally. In the U.S., Z-Wave
operates at 908 MHz, whereas in Europe it uses 868 MHz. Other countries and
regions use everything from 865 MHz to 921 MHz.
There are two signi cant advantages of the lower carrier frequency: increased
range and reduced interference. Lower frequency radio waves propagate
further. The 2.4 GHz band used by BLE and Zigbee is also used for WiFi,
Bluetooth Classic, and even your microwave oven, so there is a lot of potential
for interference.
The frequency bands used by Z-Wave tend to be much less crowded. The
downside of the lower carrier frequency is a lower data transmission speed
which ends up being almost 10 times slower than Bluetooth LE.
Z-Wave supports smaller mesh networks up to 232 devices, which is more than
suf cient for most applications.
6LoWPAN
6LoWPAN is a strangely named technology that combines two different
acronyms. The 6 refers to Internet Protocol (IP) version 6 and the LoWPAN
refers to Low-power Wireless Personal Area Network. Catchy name, I know.
6LoWPAN is essentially a new competitor for Zigbee. The primary differentiator
is that 6LoWPAN is an IP-based network like WiFi. As with Zigbee and Z-Wave,
6LoWPAN is primarily used for home automation applications and smart meters.
Local Area Network (LAN) Technologies
WiFi, perhaps even more so than Bluetooth, likely requires little introduction. If
your product requires access to the internet, and will always be used near a WiFi
access point, then WiFi is the answer. WiFi is known as a Local Area Network
(LAN) technology due to its moderate coverage area.
WiFi is fast, cheap, easy to implement, has a good operating range, and is widely
available. The biggest downside of WiFi, at least for mobile products, is the
power consumption. Because of the higher power consumption, you are usually
better off using other wireless technologies if you don’t really need the
performance offered by WiFi.
Long-distance Cellular Technologies
If your product needs access to the cloud, yet it won’t be consistently located
near a WiFi access point, then your product will likely need a cellular radio for
long distance communication.
The exact type of cellular technology required for your product depends on how
fast you need to transfer data, and to a lesser extent on where your product will
be sold.
GSM / GPRS
For a long time GSM (Global System for Mobile communication) coupled with
GPRS (General Packet Radio Service) for data transfer has been the most
commonly used cellular technology for products that don’t require large
amounts of data transfer. This is mainly due to the wide availability and the
relatively low hardware cost of GSM/GPRS hardware.
Unfortunately, that is coming to an end. Most of the cellular carriers around the
world are phasing out GSM so they can free up more bandwidth for 4G and 5G
smart phones which require huge amounts of data transfer.
Even more unfortunate, there is no obvious alternative technology, at least yet.
The most likely option is to upgrade the hardware from a GSM solution to an LTE
cellular technology, but that comes with a large price increase.
LTE
LTE is a 4G cellular technology that supports much faster data speeds than GSM.
If your product requires very fast cellular data transmission speeds, then LTE is
likely the best choice.
But if your product doesn’t really require that level of data speed, then you will
be paying for hardware you simply don’t need. An embedded GSM module can be
purchased from China for only a few dollars, whereas LTE modules can cost more
than $20. The carrier service cost for LTE will also be signi cantly higher than for
GSM.
With the huge popularity of Internet-of-Things (IoT) devices, this gap in
technology choices has become even more pronounced. This gap is in the
process of being lled, though, by several different new wireless technologies
which I’ll discuss in the next section.
Low-power Long-distance Technologies
If you require long-distance, low-data communication, as do many IoT products,
then your technology choices aren’t as clear as for other applications. This type
of network is commonly referred to as a LPWAN or Low-Power Wide Area
Network.
For example, if your product collects weather data at remote locations and
automatically uploads that data to the cloud, then a LPWAN technology is likely
needed. As I’ve already pointed out, neither GSM or LTE cellular technologies are
good ts for low-data rate applications.
There are other wireless technologies available that offer good solutions to this
problem, including LoRa, NB-IOT, and LTE-M. Unfortunately, none of these are
widely supported global standards. This makes their implementation challenging,
or impossible, for many products depending on where they will be sold.
LoRa / LoRaWAN
LoRa (short for Long-Range) enables very long-range communication of more
than 6 miles in some areas, while consuming little power. It is a
proprietary wireless technology acquired by Semtech in 2012.
LoRa uses various frequency bands depending on the region of operation. In
North America 915 MHz is used, and in Europe the frequency is 868 MHz. Other
areas may also use 169 MHz and 433 MHz as well.
LoRa refers to the underlying technology and can be directly used for peer-topeer communications. LoRaWAN refers to the upper layer networking protocol.
If you are looking for a low-power, long-distance, peer-to-peer solution, then
LoRa is a great choice. You can typically purchase LoRa modules cheaper than
LoRaWAN modules.
If you wish for your product to connect to an existing LoRaWAN network, then a
more expensive LoRaWAN module is required with the network layer included.
Unfortunately, LoRaWAN networks are only available in parts of Europe and not
in North America. This severely limits the usefulness of LoRaWAN for most
products.
Although LoRa is designed to operate over a huge range, it is not a cellular
technology that can connect to mobile networks. This makes it less complex, and
cheaper to implement, but it’s applications are limited.
For example, if your product requires long-distance access to the cloud then you
would need to also supply a LoRa gateway device for connecting to the internet.
The gateway device connects to the internet, and communicates with any
remote LoRa devices.
LoRa does not provide any single remote device a method to remotely access the
cloud, assuming there is no LoRa gateway within the operating range.
NB-IOT
Unlike LoRa/LoRaWAN, NB-IOT is a cellular technology. This means it is more
complex, more expensive to implement, and consumes more power. But, it offers
higher quality cellular connections and direct access to the internet.
NB-IOT is only intended for transmitting very small amounts of data. The biggest
downside of NB-IOT is the limited availability. No U.S. carriers support it yet, and
it is currently only being tested in Europe. But it is expected to become available
in the U.S. sometime in 2019.
This technology doesn’t likely make sense to implement in your product now, but
it will become more practical within the next couple of years.
LTE-M
If your product requires long-distance cellular access with higher data rates than
supported by either LoRa or NB-IOT, then LTE-M may be your best choice.
LTE-M is an abbreviation for LTE (Long Term Evolution) Cat-M1. This technology
is for Internet of Things devices that need to connect directly to a 4G mobile
network. It is a subset of the LTE cellular technology that is optimized for low
data rate devices running from small batteries.
LTE-M differs from standard LTE in a few critical ways. First, it is cheaper to
implement because simpler chips can be used due to the more limited
bandwidth.
Secondly, it’s optimized for reduced power consumption so as not to quickly
drain small batteries. Finally, the cellular service costs are signi cantly lower
because you aren’t using anywhere near the bandwidth required by standard
LTE.
Conclusion
The key to selecting a wireless technology is to narrow down your requirements
so you can focus exclusively on the viable technologies. The required operating
range, the data transmission speed, the power consumption, and the cost are the
primary criteria for selecting a wireless technology.
Of course, as with all things in engineering, you can’t have everything your way.
For example, a large operating range requires increased power consumption. The
same is true for faster data rates. There will always be some give and take
between these criteria. There is never a perfect solution.
If you are looking for a technology that offers long-distance, low-power, high
data speeds, and low cost, you will never nd a realistic solution. Instead, I
suggest you prioritize your design criteria and begin narrowing your choices
from there.
If you enjoyed this article please share it or if you have any questions just leave a
comment below and I will answer your questions.
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Leave a Reply
Mauricio Villalobos
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10 comments
Reply
John,
Thanks for the very through article. It´s very useful even for me as the
owner of a company dedicated to custom product design.
Although I´m not one of the engineers who are getting their hands
dirty on the hardware design, this information is extremely useful as it
allows me to better understand the requirements of my customers.
I was wondering why you didn´t include SigFox in the LPWAN section
being it the option with the cheapest modules, but I assume it is
because it isn´t that strong in the US and the future of this technology
is uncertain as of lately, so I understand you there.
Anyways, thanks a lot for the effort,
Cheers,
Mauricio
John Teel
Reply
Thank you Mauricio for the feedback! I’m glad you found it
helpful. I’ve seen a lot of other articles out there that discuss
these technologies, but I hadn’t seen any where all of the
technologies were compared and grouped together to help in the
best selection.
You are exactly right about why I left off SigFox. I decided it
would be better to leave it off the list since it’s future is uncertain
and it’s not broadly supported in the U.S. I had it on the list but
then decided it would be better to leave it off.
Thanks again for the comment!
rahul
Reply
thanku john really helpful!!!
John Teel
Reply
You are most welcome Rahul, I’m glad you found it really helpful!
Kamar
Reply
Very useful info
John Teel
Thank you Kamar!
Reply
Bandula Abeywickrema
Reply
It is very informative article, with comparison of wireless technology
in short, which I have not came across before.
John Teel
Reply
Thanks for the comment. There are countless articles out that
discuss some of these technologies, but I too haven’t seen any
that look at all of them together.
Timo
Reply
Interesting article and good comparison of the current wireless
technologies.
As I am working for a company that is impacted by the replacement of
GSM/GPRS in the near future, it is noteworthy that most of the
available replacements are only ment for data communication. Voice
communication is in most cases not possible. While data
communication can be done by many technologies, voice is narrowing
the eld to LTE and perhaps LTE-M. You can then decide if you want a
second processor for (low power) data communication (if your data
rate does allow it). There is no such thing as low power voice
communication as far as I know. I hope this will be introduced in the
near future.
John Teel
Reply
Thank you for sharing this by commenting. Very good point. I
rarely deal with voice applications over cellular, most just data, so
that was my focus.
Thanks again for the feedback!
John
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