We invited the general manager of Jiangsu Jmesh Communication Technology Co., Ltd., Mr. Wang Donglin, to explain his understanding of the current developments and trends in intelligent energy equipment, ecosystems, and the products and technological development in the applications of the IoT wireless protocols.
Even as the idea and applications for the Internet of Things have become familiar and accepted by the market, its industrial uses as a first developed component have been widespread in China for years, providing efficient and convenient services for Chinese people.
The National Energy Commission of China issued its “13th Five-Year Plan for Energy Development” recently, in which construction of intelligent energy systems and smart grids are clearly stated strategic goals. This plan also requires the industry to focus on breakthroughs in grid connection, energy storage, and micro grid technologies to build “Internet+” intelligent energy sources, improve adaptability of power grids, increase the utilization of new energy sources, develop advanced and efficient power-saving technologies, and take a leading role in the energy technologies competition.
Taking the smart electricity meter as an example, it should not only be able to measure power consumption accurately, but also monitor it in real time to promptly reflect consumption so as to make it convenient for users to pay their energy bills. Provincial, municipal, and county governments in China have begun to install intelligent water, electricity, gas and heat meters in homes and commercial premises, as well as concentrated meter reading systems synchronously, creating a huge market for intelligent energy software and hardware. To navigate in such new waters, Shenzhen Jmesh Communication Technology Co., Ltd. (Jmesh) sought out Silicon Labs for help. Jmesh relies on our accumulated technical expertise in micro power wireless communication modules, smart meter reading hardware, and software to help State Power Grid and provincial, municipal, and county governments accelerate the completion of the strategic goal of building intelligent energy ecosystems.
Please tell us your experiences and personal ideas regarding the Internet of Things market and product designs.
The need for the management of water, electricity, gas, and heat are pertinent to every home, and there is a huge market for it. In recent years, power saving and carbon emission reduction are prevailing topics worldwide, leading to the boom of renewable energies. The entire industry is greatly interested in how to use newly developed semi-conductor technologies and IoT wireless communication technologies as well as how to further realize an “intelligent energy” ecosystem.
Jmesh entered the electricity meter market in 2011. We have focused on the design of micro power communication modules of various smart meters, development of information security solutions, data collecting platforms, and backend backbone networks since the beginning, becoming a leader in market development and technological innovations in the intelligent energy industry. For the next stage of development, we think that there are three must-have elements of the concentrated meter reading system for the intelligent energy industry: design of a stabilized wireless and narrow/wide band communication network, low power consumption and efficient data transmission, and hard and software-incorporated data service and collecting platform.
Therefore, Jmesh wants to upgrade its mission from a supplier of communication modules, meter reading equipment, and system solutions to a “service provider for the Internet of Things,” helping public organizations and companies construct intelligent energy ecosystems to provide intelligent energy management services.
Please describe the company culture and special features of Jmesh and its unique strategy in the Internet of Things market.
Jmesh has two research centers in Shenzhen and Hefei, respectively, and collaborates with Chinese universities in carrying out basic algorithmic research on a long-term basis. We continuously grows and expands in the IoT market and intelligent power grid fields fueled by our technological expertise and unique insights into customer demands and industry development, winning multiple bids of power grid companies at the provincial level.
Jmesh employs the best technical talents in the industry. Its core R&D team is familiar with technical standards for various electricity meters and the data collection equipment of the National Power Grid and Southern Power Grid. It has integrated electricity metering and wireless communication functions together to be applied in the development of data collection equipment for user power consumption, which is the advantage of Jmesh over its competitors in the area of wireless information collection. Jmesh also can provide comprehensive 4-in-1 data collection solutions for reading water, electricity, gas, and heat meters.
What are some features and advantages of Jmesh's products?
Smart electricity metering is an important component of the intelligent power grid system and the “terminal” of duplex intelligent power supply. Its functions include duplex metering, automatic data collection, tiered pricing, time-of-use price, freezing, control, and monitoring. When entering the electricity meter market in 2005, Jmesh first focused on carrier wave communication. Following the rapid development of wireless communication, Jmesh started to research, develop, and implement the 2.4 GHz wireless wideband ZigBee solution in 2007-2008, and further began to adopt Sub-GHz and ZigBee wireless chips, modules, and software protocol stacks of Silicon Labs in 2010 to provide better networking capability, stability, and lower power consumption for customers.
Jmesh's comprehensive 4-in-1 data collection solution for reading water, electricity, gas, and heat meters uses a low-power wireless protocol. For water, gas, and heat meters with wireless interfaces, the communication module on a Type I Data Collector (or electricity meter) can be retrofitted to form a mesh network and star network all wirelessly connected. For water, gas, and heat meters with wired interfaces, a protocol translator is added to connect them into the collection system.
Jmesh's 4-in-1 data collection solution for water, electricity, gas, and heat meters.
We also provide single-phase remote prepaid smart electricity meters, single-phase local prepaid smart electricity meters, and three-phase remote prepaid smart electricity meters (wireless/remote), as well as concentrators and servers for the wireless electricity data collection.
Wireless electricity usage data collection system.
What made you choose Silicon Labs as your ideal semiconductor partner?
Silicon Labs’ sub-GHz solutions are among the best in the industry, which include high-performance wireless connections and 8 or 32-bit micro controllers, radio transmitters, responders, and transceiver options with ultra-low power consumption. Their 2.4 GHz ZigBee chips and modules also have the best node expandability in the industry, with over 200 nodes per AP (Access Point), which is a key technological achievement that hasn’t been accomplished by any other suppliers. Therefore, Jmesh chooses the wireless products of Silicon Labs and continuously works with it to develop intelligent energy related equipment with even better performance, lower power ratings, and higher cost-benefit ratios.
Jmesh has used high performance and low current Si4438 EZRadioPRO ISM band transceiver family of Silicon Labs covering a frequency band of 425-525 MHz, which includes complete transmitter, receiver, and transceiver product lines for various applications. Si4438 is specially designed for the electricity meter market in China. It is capable of reliable remote communication, delivering up to +20 dBm output power via its PA with an outstanding receiving sensitivity of 124 dBm, while having extremely low active and standby current consumption. Its 75 mA transmitting current consumption (+20 dBm output power), 14 mA receiving mode current consumption, extremely low 40 nA standby current and short wakeup time all ensure a longer battery life even in the harshest applications. High output power and sensitivity can deliver an outstanding 144 dB link budget, allowing expansion and highly reliable communication links. After tens of millions of on-site installations and operations in many years, highly reliable performance of products designed upon Silicon Labs solutions is fully accepted by power sector customers.
Jmesh also has adopted EM35x series ZigBee chips of Silicon Labs among its wireless wideband products.
Please tell us about your views on IoT development and also the future of the Chinese IoT market.
“Intelligent energy” is a long-term goal for IoT application, which will very extensively affect our lives. For China, with its huge population, the construction of intelligent energy systems will revolutionize society and have huge business potential. Now, with the strong support of the Chinese government and gradual availability of equipment and technical know-how, the spring of intelligent energy in China is right in front of us.
Currently, the IoT market is full of various suppliers and technologies. However, for intelligent energy systems that require stricter network stability, data security, and energy-saving standards, suppliers must have core technologies in soft- and hardware, networking, security measures, and data collection platforms to provide a comprehensive IoT intelligent energy management service which supports water, electricity, gas, and heat metering. In addition, it is even more important to participate in the development of national standards related to intelligent power grid, meter reading system and data collection in their early stages so as to keep up with industry development trends.
Therefore, Jmesh will continuously focus on the requirements and needs of the State Power Grid, Southern Power Grid, and other nationwide power service agencies for intelligent energy systems and work with Silicon Labs. Jmesh will also collaborate with University of Science and Technology of China, home appliance manufacturers, and new Internet hardware manufacturers to develop secure and interconnected API to become the most trusted intelligent energy ecosystem partner in China.
In the first part of this series on best practices and debug tips, a Revision Control System was introduced, and how it can stash your design files safely away and help you find differences across design files. In this section, you will learn what it takes to be a success with building your own hardware.
Start Development on a Breadboard
When starting a new project on EFM32, you may have followed some of the examples of this book and felt that you have learned enough to develop your own EFM32 solution on your own custom Printed Circuit Board (PCB). But don’t make that leap too fast!
1. Test out the pieces one at a time first
For best results, every project should start with a “breadboarding” phase where you assemble a Starter Kit and a breakout board for each major device in the design. While you can read specifications for the devices in your design many times over, you don’t truly learn how to use a device until you have tried to interact with it from software. Just the experience of connecting a device to your Starter Kit and trying to talk to it over the electrical interface will yield many insights that are not gleaned simply from reading the spec. While some specs can make a lot of sense at first, you will soon discover that the spec doesn’t cover everything needed to bring up a device and start using it, or at best it glosses over some important information that requires an extra signal wire, an extra external circuit, or a number of other important details.
2. Find or make your own breakout board for each device
In order to work with external devices, you need to find a breakout board, evaluation, or development kit for each device in the design. If you cannot locate one for a device (or if it is too expensive), you can usually build one yourself by following the instructions of Chapter 9 of this book. If that is not possible, for example if your device has some difficult-to-solder device package like BGA, you can sometimes find alternate packages for chips that have the same electrical properties with an easier-to-solder package.
If your device requires extensive support circuitry to function, for example a special voltage regulator, it can be completely worthwhile to develop your own evaluation PCB for that device, for your own personal use, since developing such a board will prove that the pinout, footprint and support circuitry of your device is well understood before you go to build the whole system PCB. These footprint files can then be reused in your system design, and you will know that they are already completely verified.
3. Aim for basic functionality only
Once you connect your evaluation devices to the Starter Kit for testing, the focus should be to just get the part to basically function. Since you are connecting over jumper wires, there are situations where the electrical requirements of the signal interface won’t work at full speed, so keep the speed to the slowest allowable for the electrical interface and at the lowest drive strength on the EFM32 GPIO outputs. Write code to do something simple, like reading a device ID register or making a simple write to make something happen on the device, before going into further functionality. It may be possible that certain frequencies are unreachable, due to the complicated signal integrity issues that can happen over jumper wires, so don’t expect too much out of a breadboard mockup.
The point of this process is to learn as much as you can about the requirements of the device before you go to design a custom PCB solution and integrate the device driver into the system software. This isolates any issues to a single subsystem and makes your final development an exercise of system integration.
Keys to Breadboarding Success:
Plan a Prototype Build
Once your breadboarding experiments are done and you have settled on the devices that will make up your EFM32 solution, it is time to develop a custom PCB to house all of those components together as a single system. While it is tempting to also define the enclosure at this time and develop a tiny board that fits within the target enclosure, it is a better idea to develop your first custom PCB as a large test system that is focused on testing and development only.
1. Use testpoints religiously
A built-for-test PCB is a version of the final solution that includes access to all signals in the design as testpoints. Any signal in the design with a testpoint can then be probed either by a multimeter, oscilloscope, or logic analyzer. A testpoint can be an exposed “pad” of copper, a through-hole junction that allows a header pin and jumper wire to be applied, or even a loop of metal for a probe clip. It is also a good idea to place all components and test points on the top side of the built-for-test board, so that once again, debugging is easier because you can get to everything at once without needing to flip the board over.
To see the types of test points, just look at the back of your Starter Kit. The plated through-hole test points are the ones that we have soldered header pins into. The small gold round pads are the surface-mount test pads, which are suitable for probing or soldering tiny wires in which a small probe clip can be attached.
2. Plan a for a hardware design spin
By planning a built-for-test version of the PCB, it will require at least one “spin” or redesign the board for the production solution. It is very rare, almost impossible, to design a board that goes from first test to production in a single spin. A built-for-test PCB allows you to interrogate the system during bring-up and study the electrical interfaces between devices easily, without resorting to special soldering skills to attach probe points to electrical signals. A fully-featured through-hole JTAG debugger connector should be added to fully interact with the Simplicity Studio IDE as if your design was a Starter Kit. While it is possible to develop production boards with UART-only programming, you will lose debugging functionality without a JTAG debug header, which is the 3M N2520-5002RB available here .
You can study power consumption of each device in the system by placing a precision resistor around 1 ohm between the power supply and each device, and then measuring (or scoping) the voltage difference across the precision resistor.
3. Use a bigger, better version of the EFM32 part than you think you will need in production
When you develop your first custom PCB version of a design, use a version of the EFM32 family of parts that have more flash and RAM than what you think that your final solution will require. You can sometimes keep the same pin count and footprint but gain additional flash and RAM by building your design with a more capable part than your final production solution. The “Debug” builds in Simplicity Studio require more flash storage and RAM than the “Release” builds that use optimizers to reduce memory footprint, so by moving up to more capable parts during the prototyping stage, you will make debug possible. You can also move up to more capable families with more pins if it will make the job of debugging your solution easier. Just be careful not to rely upon features of the upgraded family that will disappear when you move to your production solution. A selector guide that shows the capabilities, capacities, and pin counts of each device in each family is found here.
4. Connect to your own PCB over JTAG as if it were a Starter Kit
When your built-for-test PCB arrives, to use the JTAG debug header on your PCB, you can attach an IDT cable, such as the Assmann H3CCH-2018G available here to the JTAG connector on the Starter Kit. Then, under the Kit Manager tile in Simplicity Studio (after you have connected the Starter Kit to your computer) select Debug Mode: Out.
You may have to go back to the home page of Simplicity Studio and select the “Target Part.” Do that, right click on the Starter Kit that is detected and select the choice for “Select Target Part...”
In the “Target Selection for EFM32...” window that opens, change the Target Interface to SWD, ignore any warnings that it produces (as long as you are connecting to an EFM32 part) and then click the Detect Target button. Press the Yes button for any popup windows that appear until the Part label shows your actual device on your custom PCB. This will prove that the JTAG connection from your Starter Kit to the EFM32 part on your custom PCB is being detected by Simplicity Studio on your computer.
With all of these steps completed, whenever you launch your project in Simplicity Studio IDE, the part used for your project must match the part found in the target selection in order for flash programming and debugging to commence. This allows you to debug your custom PCB as if it were a Starter Kit.
Keys to Prototyping Success
In the next section, tips for software development and debug will be introduced.
As a computer engineer of 20 years and a developer of EFM32 projects for over two years, I am lucky to have a vast background of experience from which to develop complex computer engineering projects. That’s not required anymore, thanks to tools like Silicon Labs’ Simplicity Studio software and the wide availability of hardware debugger tools such as the EFM32 Starter Kits. With platforms like these, anyone can get started on embedded development quickly and cheaply. Within minutes of receiving your Starter Kit, you can be single-stepping through your very own hardware-enabled embedded solution. My work on this book should give you a good idea of how to get started to make use of all of the bundled peripherals within the EFM32 line of chips.
However, just because you can follow some examples and get lights to blink and electronics to start to function in an example doesn’t always translate into success in your own projects. My years of experience have guided me to make the correct upfront decisions on how the hardware should be connected, how the software should be architected, and my experience is right there whenever things go wrong, giving me intuition on what to do next in the debugging process to solve the problem.
But what if you don’t have years of experience to lean on? How can you find success that won’t take years and years to master? My answer to that question is in the following posts of this series, where I will attempt to distill as many golden nuggets of wisdom that I had to learn the hard way. You may want to read this guide a few times, and then read it again later when you are stuck on a problem. It could be the key to solving any number of issues that pop up along the way.
Some of these tips relate to the Simplicity Studio Integrated Developer Environment (IDE) bugs and nuances that may change as Simplicity Studio is improved over time. But most of the tips in this guide are generic and should apply to all facets of your design from start to finish.
There are six parts to this series:
Part 1 - Use a Version Control System
Before you get started with a new design, take the time to set up a version control system for all of your design work. This may seem obvious to many, since these systems are so widespread in software development. But it is very important for embedded development, where a single character difference in a source code file can sometimes be the difference between a working solution and one that completely fails.
1. Find differences across revisions
Version control systems allow your work to be saved at various snapshots as the design progresses, and allows you to compare differences in your files from each snapshot. These systems are freely available and can be installed on all types of operating systems (Windows, Mac and Linux). The most popular tools today are SVN and Git. I am a user of both systems but I prefer Git these days because it keeps the complete repository including all of the revision history available locally on your computer and you can work completely offline, and then “push” the changes to a remote server later. SVN, on the other hand, only keeps the most recent revision on your local computer and requires an active connection to the server to fetch past revisions and other history information.
The code examples of this very book are stored in an online Git repository on Github, so it would make sense for you start by “cloning” that repository to your local hard drive and making changes, then experiment with the Git command line or GUI tools to look for the differences in the files. Setting up and using Git is beyond the scope of this guide, but there are many tutorials out there from which to learn.
2. (Optional) Set up Git in Simplicity Studio
Simplicity Studio can be configured to work with Git within the Simplicity Studio IDE. This allows you to commit changes and look for differences across files right within the IDE. Details of how to get that setup can be found on the Silicon Labs Community. Note that the integration is not required to use revision control, and I don’t use the integration on my computer. I simply run the command line version of Git or the GUI tool on my local folders to make my commits and review differences.
3. Store all your files in a repo, not just source code
Whenever you start a new project, set up a new version control repository (called a “repo” for shorthand) to store all of the files that pertain to that project. Go ahead and store all of your specifications and datasheets, design documents, spreadsheets, and so on, in that repo. You never know when that document you are viewing online may become unavailable or changed by the manufacturer. It’s good to have a copy in a safe place where it is bundled with the design files. Don’t stop at documents either. Store the schematics and layout files for your project in version control as well.
4. Keep a backup of the repo online
It is best to get an online service such as Github, Atlassian, Google Drive, Microsoft OneDrive, or any other online backup service to keep an extra backup copy of the repo. When your hard drive crashes or your laptop goes missing, cloning the last server copy of a Git repo is a very quick and easy option to get your design files back on your computer.
5. Commit early, and often
Once you have your repo set up and keeping track of your files, make sure to “commit” your design files whenever you reach an important milestone in your project. When you have just been able to communicate to some chip for the first time, make a commit of the code and specify in the log message exactly the current state of the project even if the source code is a mess of a hack to get it to that point (which it sometimes requires) . For example, “Got accelerometer device ID read out over SPI” is a great message to yourself letting you know that the code that is then committed to the repo basically functions. What usually happens next is that you clean up the code to make it fancier, more readable and better performing, and sometimes that process breaks the code. Sometimes the reason for why the code was broken is obvious and you are on your way, but sometimes everything you do to try to fix the issue doesn’t work and you are back at square one with a solution that no longer functions at all. If you have a committed version of the working code in the repo, all you need to do is first commit your new code to the repo, then rollback your changes on your local drive and see if that original solution still works, which lets you know that at least you aren’t going crazy. You can then use the difference tools of the revision control system to show differences from the first version to the second version and eventually isolate and fix the issue.
6. Use version control to isolate hardware issues
One key difference between embedded development and pure software development is that hardware can change from run-to-run on an embedded application. When you run the solution the first time, everything works, and then you make some changes and things stop working. It may seem like the software, but perhaps a wire has wiggled loose somewhere? By committing your changes to the repo, then rolling back to the last version that worked, you can be sure that the problem is not software, find and fix the loose wire, then update the repo back to the most current version and continue development.
Keys to Success with Version Control
In the part two of the series, we will learn about the virtues of breadboarding your project before you make a PCB.
Location: Hall 4A / 4A-128, Exhibition Centre 90471 Nürnberg, Germany
Date: 14 - 16 March 2017
09:00 - 18:00 (14 and 15 March)
09:00 - 17:00 (16 March)
Embedded world is the leading international fair for embedded systems. Be it security for electronic systems, distributed intelligence, the Internet of Things or e-mobility and energy efficiency – the embedded world trade fair in Nuremberg enables you to experience the whole world of embedded systems.
The Silicon Labs’ team will participate in embedded world and deliver the following presentations, meet us at our booth: Hall 4A / 4A-128.
Driving Wi-Fi, ZigBee and Thread Wireless Coexistence in the 2.4 GHz Band
Presenter: Tom Pannell
Date/Time: Tuesday, March 14 at 11:30 am -12:00 pm
Running Your Embedded System at 0 MIPS – The Power of Autonomy
Presenter: Oivind Loe
Date/Time: Tuesday, March 14 at 4:00 - 4:30 pm
Safe for the Future
Presenter: Tyson Tuttle
Date/Time: Wednesday, March 15 at 10:30 - 11:30 am
Which IoT Protocol Should I Use for My System?
Presenter Christian Legare
Date/Time: Wednesday, March 15 at 11:00 - 11:30 am
Advanced Use Cases for Linked DMA
Presenter Josh Norem
Date/Time: Thursday, March 16 at 9:30 - 10:00 am
Exploring the Hidden Costs of Using a 99-Cent Wireless SoC
Presenter Tom Nordman
Date/Time: Thursday, March 16 at 10:00 - 10:30 am
Top 5 Key Considerations for Your RTOS-based Design
Presenter: Jean Labrosse
Date/Time: Thursday, March 16 at 10:30 - 11:00 am
Security Tradeoffs and Commissioning Methods for IoT Wireless Protocols
Presenter: Dr. Lars Lydersen
Date/Time: Thursday, March 16 at 11:30 am - 12:00 pm
The Anatomy of a Secure Thing of the Internet
Presenter: Dr. Lars Lydersen
Date/Time: Thursday, March 16 at 1:30 - 2:00 pm
We spent last week at the Consumer Electronics Show, and what a week it was. 2016 was clearly dominated by voice control. Here are or some thoughts on that and other observations from Skip Ashton, Silicon Labs' VP of software engineering.
The usual crazy crowd at CES to start 2017. The transformation of Sands Expo into the center of the Smart Home brought most of the smart home market out to show off what they are working on. This means the Alliances – zigbee, Thread, ZWave, and OCF all had their booths. Large companies, equipment suppliers and even service providers active in the space like Comcast were there to show existing and new products off.
The overall theme had to be the dominance of voice control for everything. The wild success of Amazon Echo means you cannot have a connected product without having an Alexa skill. As I look today, there are now over 8,200 skills Alexa has and more than 4,000 of these were added in the last 90 days. This means smart home systems like Lutron, Crestron, Control 4, SmartThings, or IRIS are enabled; but so are lighting products from Philips, OSRAM and others. Somfy launched a new system from myFox and it is already integrated. We once saw a focus on touchscreen controllers for device control. These products, and their associated mobile apps seem to be focused on voice as the primary interface. Obviously beyond Alexa there is Siri and the Google Assistant also wanting to be your voice control.
The other notable event was the announcement of dotdot and demonstration of it running over Thread in the zigbee and Thread booths. This is a major step forward for the industry in use of an agnostic application layer that can be used across different physical layers to control devices. Dotdot seemed to be really well received by the market and by the press.
This seemed like one of the busiest CES shows I’ve attended. This was due to the large number of meetings. This is not why people come to CES, they want to see what is on display. So what did the booths have this year?
zigbee – I think the best looking zigbee booth ever. There was the wall with more than 100 zigbee products, plus the normal company pod displays. The wall of devices drew a lot of interest and really showed the wide range of products. The dotdot demo looked excellent and also drew a lot of questions and interest. The booth was constantly busy and there was a full set of press and analyst briefings on the state of zigbee plus what dotdot means moving forward.
The zigbee Wall of Devices
Thread – The Thread booth also looked excellent and had a large wall with a demonstration of dotdot, Weave, and OCF running over Thread plus the individual company displays. The Thread booth was also very busy with new companies, press, and analysts asking questions. The market knowledge of Thread and its potential continues to grow and the announcement of dotdot starts to put the pieces together for those looking to develop product.
Demonstration of dotdot devices running on Thread
The OCF booth was also full of a wide variety of companies from the OCF ecosystem.
For device makers – in addition to having to talk about their voice control capabilities people really wanted to show the wide range of technologies they support. Here’s an example from Leedarson.
For the large appliance manufacturers, the approach to the smart home at this CES was not devices but instead high-end smart appliances and their OS. Below is the Samsung and Haier booths and their appliances. Note this is a small portion of the Samsung booth, which was rather large but did not include the SmartThings devices (included last year) or any Artik devices.
I also had to put in a picture of the WNC section (of the ZWave booth) which had industrial IoT showing a smart meter and communications hub (and that is enabled by Silicon Labs).
Below is ZWave's main CES booth
As you know, the number of devices for the connected home is growing faster than you can say “Alexa.” And as this world expands, it’s important to understand the way in which all of these devices communicate with each other.
That’s where wireless communication protocols come into play. Let’s take a look at the most commonly used wireless protocols and discuss which use cases are best for each.
For low-data-rate applications like home security and automation, sub-GHz networks (operating at frequencies below 1 GHz) offer substantive benefits over the more powerful and feature-rich protocols such as Wi-Fi, Bluetooth™ and ZigBee operating in the 2.4 GHz band.
Range is one area where a sub-GHz network shines. Narrowband transmissions can operate uninterrupted for a kilometer or more. They transmit data to distant hubs without hopping from node to node. However, this longer range can also come with increased interference from adjacent devices. Lower interference can be a benefit, in regions where a wide range of sub-GHz frequencies, and these frequencies are less ‘crowded’ than the 2.4 GHz band. However, in some regions there are few available sub-GHz channels and they may have duty cycle restrictions limiting the time a device can be transmitting. Finally, sub-GHz wireless also uses very little power compared to 2.4 GHz protocols.
However, sub-GHz networks aren’t a perfect fit for every aspect of the connected home. Many of the existing sub-GHz networks use proprietary protocols and are closed systems. Such systems often require application translation to communicate with other systems. Intra-home communication, and communication to a data services and controls that might reside in the cloud, can be more complex using sub-GHz wireless.
Wi-Fi 802.11 b/g/n
Wi-Fi is the best known protocol by far, because most of us use it in our own homes every day, and have for more than a decade. This wide adoption has been fostered by the standards and upgrades The Institute of Electrical and Electronics Engineers (IEEE) provides through letter designations (b/g/n), while the Wi-Fi Alliance manages certification and branding of devices.
The chief advantage of Wi-Fi is its familiarity, the perception that it is “easy” compared to other protocols, and its ubiquity in existing homes. After all, the precursor to Wi-Fi was first developed in 1991. At this point most tech-savvy homeowners (the likely customer base for current connected home products) can reset a Wi-Fi router to troubleshoot basic issues.
Wi-Fi defines a MAC layer protocol and security but it does not define application objects for devices and how they communicate. This means each manufacturer can define their own application level protocol and device to device communication is complex or impossible unless two companies work closely together to define them. This limits Wi-Fi usage in the device to device market for the connected home. Wi-Fi also assumes a central access point model of a network which means if that access point is not operating the network stops functioning.
Wi-Fi consumes a great deal of power relative to other protocols so while suitable for powered devices it does not do as well in applications where battery powered operation is critical. Wi-Fi has also shown issues around scalability. For example, some routers are configured to only support a maximum of 15 devices where the connected home is expected to have closer to 100 devices.
Another issue is competition on the Wi-Fi network due to the variety of data sources. If you have streaming video competing with your thermostat, both data streams may not get the bandwidth they need. And if you thought having your streaming TV show competing with your kids’ video game download was inconvenient, imagine having your thermostat trying to get in on the bandwidth, too.
Bluetooth™ with Low Energy Functionality
Bluetooth is a short-range communications protocol that is ubiquitous in smartphones applications. It doesn’t require a special gateway to function because it already uses the smartphone or mobile devices, but it does have some drawbacks. It is only a point-to-point network, which limits its range and reliability. If your smart phone is not in range or not in the home then connectivity is lost. Bluetooth does not currently natively support IP addressing but this is being worked on as an update to the Bluetooth Standards.
Bluetooth does have standard application protocols but these are generally related to the phone or PC use cases and not device to device communication in the connected home.
ZigBee was first standardized in 2004, and features lower power consumption relative to Wi-Fi. It operates on the IEEE’s 802.15.4 physical radio specification (as opposed to the more familiar 802.11 of Wi-Fi fame). ZigBee is used heavily in home automation mesh networks currently, as well as in many industrial applications.
ZigBee has created a set of application protocols defining a wide range of devices and their communication patterns for device to device usage in home and businesses. These application protocols were developed within an Alliance of companies so there is a healthy ecosystem of products as well as competing silicon providers.
There are numerous advantages to the ZigBee protocol, including its reliability, scalability and ability to self-heal its mesh network:
Reliability: Devices on a ZigBee network can communicate with each other even if the gateway goes down or there is no gateway to begin with.
Scalability: ZigBee and other 802.15.4 protocols are not constrained by the number of devices they can have per router. You can add dozens, even hundreds, of devices without reaching an upper limit.
Self-Healing: If the Personal Area Network (or PAN) coordinator for the mesh network is no longer available or is inoperable, the mesh seamlessly fails over and continues to function. Think of it like RAID for your computer—if one hard drive goes down, then the mirrored second hard drive takes over so that your work isn’t interrupted. In the case of home automation, it means that your thermostat still works even if your gateway is down.
The Z-Wave protocol is primarily devoted to home control and monitoring, and is proprietary in nature. Home security companies use the Z-Wave wireless protocol to create networks of door/window sensors, fire detectors, thermostats and other home automation devices that are accessible through high-level applications or even over the Web. Z-Wave functions best in low-bandwidth, sub-GHz deployments.
Z-Wave has created an application protocol to standardize how devices communicate with each other to allow true device to device communication in the home. However, this standard is controlled by one company making growth and expansion difficult. The application layer protocol is not IP friendly and required translation into IP protocols for device to cloud or phone communications.
Z-Wave is not an open standard and requires both address and application translation to communicate with devices on the internet. Z-Wave requires a gateway to function creating a single point of failure in the networks. Additionally, the protocol assumes that devices are static, disallowing mobile devices (like remote controls) from joining the network.
Thread is a new open standard that assigns an Internet Protocol (IP) address to every device on a network, and that IP address extends through the node. Thread provides device-to-device communication without the need for an application gateway.
Thread presents three major advantages:
Scalability: The average connected home will host a hundred devices. If that sounds like a lot, just remember that every window and door will have a sensor, and every room will be monitored for temperature and humidity. At that rate, complexity and scale grows exponentially.
Interoperability: With so many devices in play within a single mesh network, it’s important that they all communicate with each other and with the home owner in an intelligent and effective manner.
Less expensive and simpler hardware:
It’s not a new story that as a technology becomes more widely adopted the cost of devices tends to go down. (Look at what happened with flat-screen televisions over the last decade.) IP-based technology is well known and easy to implement.
While Thread is in development, there’s no need to hold off on developing products for the connected home. Any product using existing 802.15.4 silicon can be updated over-the-air (OTA) to the Thread IP-based protocol. This allows continued deployment of existing systems knowing they can be upgraded to Thread when the system is ready.
Security and the Connected Home
Security is built into many of the existing mesh-network connected home protocols at a deep level in the software stack, for example, using AES encryption at the 802.15.4 MAC layer. Traffic is always encrypted, and with the addition of authentication technology, all nodes will have the capability to require authentication to communicate with each other and the network.
Even devices using low level security in the software stacks are only as secure as the method used to install the keys in new devices. Weaknesses in this key installation or device bring up then require rekeying of the entire system.
IP Connectivity and the Connected Home
The existing protocols in the home are a mix of IP and not-IP stacks. Other markets and networks have converged onto IP because it offers a number of different addressing, routing and security mechanisms that can be selected for a given network or device and still allow end to end addressability and routing of messages without application layer translation. The rapid expansion of the Internet into other industries and market segments is an indication of how this technology shift opens up innovation and rapid development of new services and devices over the appropriate IP infrastructure.
The use of IP also allows a mix of underlying technologies with bridging devices between the different MAC/PHY so that an application running on your PC at home connected over Ethernet can also run wirelessly to your cell phone using Wi-Fi or a cellular connection. This type of seamless connectivity is important in many new application areas where consumers expect control while in their home but also from their phone when traveling.
The Connected Home is an area where large numbers of companies are innovating and creating new devices and services. Some of these services require high bandwidth and are more suitable for using Wi-Fi, while others are constrained battery operated sensors that would prefer using the 802.15.4 lower power radios and a ZigBee stack today, migrating to a Thread stack in the future.
As the Internet of Things and the Connected Home continue to explode in popularity, it won’t be uncommon to have several protocols running simultaneously in your home, just like you do in your smartphone. It isn’t a case of one protocol “winning,” but rather finding the right combinations of protocols to keep your IoT applications happily communicating with each other, the gateway, the cloud, and the consumer.
What applications do you anticipate enabling your home? We may not be getting our flying cars anytime soon, but with the proliferation of devices and protocols available, we’ll soon have connected homes that function seamlessly to make our environments more convenient, comfortable and energy-friendly.
We had the pleasure of speaking with Øyvind Birkenes, CEO of Airthings. The mission of his company is to make radon detectors just as prevalent as smoke detectors in both private and public spaces. Airthings’ Wave, a smart radon detector, couples sleek design with cutting-edge sensing technology to save lives. Airthings Wave is an IoT-based solution that helps home and business owners detect and monitor environmental radon levels.
Mr. Birkenes, I understand you’re launching exciting technology this week at CES 2017. But for readers just hearing about you, tell us about Airthings.
We’re based in Norway and opened the shop in 2008. Our company is made up of a great group of scientists, engineers, and other technology professionals with a core mission of ensuring people around the world can truly take control of their air quality. Our focus is to develop products that easily monitor and identify radon levels in indoor air. We are world leaders in radon monitors today, and the US is our biggest market. We are excited to launch the new Airthings Wave smart radon detector at CES. It provides consumers with critical, potentially life-saving information on indoor air quality that’s accessible via their smartphone or tablet.
And why radon detection in particular? Why is that Airthings’ passion?
We care about radon detection because exposure to it is actually the leading cause of lung cancer in the nonsmoking population, and most people don’t realize this. Radon kills around 10 times more people than house fires and carbon monoxide. Radon simply carries immense health risks, and we are determined to improve health and safety for everyone on this specific front.
Radon levels also fluctuate depending on climate, on a home’s foundation, even the earth’s movements; there are actually many variables, so long-term monitoring is crucial. Radon detection has been ignored in many ways by technology in our opinion, so we were particularly inspired to provide consumers with a significant advancement that could vastly improve their home and office safety.
And what are you launching at CES this week?
We’ve unveiled our brand-new Smart Radon Detector here at CES. The Airthings Wave is quick to setup and easy to use. Simply mount the device to the wall or ceiling with a single screw and immediately start monitoring radon levels as well as temperature and humidity inside your home. Download the free Airthings mobile app, register, pair the device, and start monitoring your air quality.
The fluctuating nature of radon makes short- and long-term measuring essential and with the Wave you will be able to view all real-time and historical data to compare over time. In addition, the user will receive alerts from the mobile app. Thanks to Proximity Detection enabled by Silicon Labs’ SI1153-AA00-GMR, the user can simply wave in front of the device to know the air quality. Thanks to color codes, radon and air quality levels are easy for everyone to understand. The ability to know your radon levels without having a smartphone or tablet is very important. This allows everyone in the home to see the air quality.
Tell us what Silicon Labs’ products you’re using to craft solutions for your customers and why you picked them?
We actually use two key Silicon Labs products in our new product. We like the I2C Humidity and Temperature Sensor—the Si7020-A20-GMR—as well as a Proximity/Ambient Light Sensor IC—the SI1153-AA00-GMR. We looked at many products, but both of these provided just the technology what we needed. They’re also priced very competitively.
And now of course our eternal Bonus Question in the IoT Heroes series: Where do you see the IoT heading in the next 5–8 years given your industry vantage point?
We are going to just see a myriad of unique devices becoming connected to the internet, and lots of resulting data generated. And over time, much more meaningful use of the data will transform our environments. We will see a lot more interoperability between systems on the cloud side, rather than individual sensors talk locally to each other on some specific RF protocol. With today’s communication platforms like Bluetooth, WiFi, Thread, and others, it’s getting easier to transfer information to the cloud, than to connect all devices locally. Thus, I don’t believe we will see one winning RF protocol for the IoT even 5-8 years out.