Driving global success of the LoRaWAN protocol

LoRaWAN 1.0 draft specification has passed the review period within LoRa Alliance, making it one step closer to ratification. As a LoRa Alliance member and in order to increase public awareness of LoRa RF technology, Espotel will launch an IoT campaign for the rest of the year.

Weatherproof LoRa gateway with Multitech Conduit
in a box and improved 868 MHz antenna.

An open and free of charge LoRa gateway located at the roof of  Espotel HQ in Espoo Finland will play central role within the campaign. The gateway is implemented with Multitech MultiConnect Conduit IoT Gateway with LoRa extension, located inside an IP65 classified plastic chassis for weather resistance and connected to Taoglas Omni-directional Outdoor 868 MHz ISM-band dipole antenna. Multitech Conduit gateway and mDot LoRa module conform with the LoRaWAN 1.0 protocol specification.

Expected network coverage spans over the southern part of the city of Espoo, including Aalto University campus in Otaniemi.

Expected coverage of the Espotel open LoRa network.

Espotel will organize and sponsor events like hackathons and other developer-oriented activities in order to provide hands-on experiences with capabilities of the radio technology. ARM mbed development environment makes it easy to start implementing custom applications. As the official ARM mbed Ecosystem partner, Espotel is committed to leverage mbed technology and bring platform support to the environment.

Example device RaspberryPi2 retrofitted with Multitech mDot LoRa module.

Together with technology partners like IBM, Multitech and Semtech, Espotel will organize business events to increase awareness of benefits of LoRa technology among decision makers and influencers within different industries.

Within the LoRa Alliance, Espotel is actively driving LoRaWAN conformance certification process, and intents to be become an Alliance acknowledged LoRaWAN conformance certification house. This is natural extension to the test and certification services provided by Espotel's accredited laboratory facilities in Finland.

This short video (2:33) gives a nice overview of our laboratory facilities. Our reference customer design, Enevo smart waste sensor is acting as a case example of testing service:
https://www.youtube.com/watch?v=JaU-J7Im144

LoRa Gateway with ARM mbed and IBM cloud support

Early review of the new IOT Gateway from Multitech, making IOT implementations yet another step faster and easier.

MultiConnect Conduit is soon to be available new IOT gateway from Multitech Systems inc. The gateway has high performance 7-band cellular data modem for internet connectivity in global operation.

Multitech Conduit IOT gateway and LoRa mDot module from Multitech.

Due to my deep interest to LoRa RF technology, I just got an early engineering sample with 868 MHz LoRa extension module for evaluation use. This is one of the very first Conduit units in Europe. Multitech also provides mDot modules for end device implementation. Espotel already uses LoRa mDots in a customer pilot project. The reason why Espotel has selected Multitech as it's LoRa gateway supplier is that both companies are in close co-operation with ARM and IBM, and members of LoRa Alliance.

Conduit runs developer-friendly Linux operating system with support for many different programming languages, including C/C++, Python, Ruby, Pearl, C#, Java, Node.js and Node-RED.
Node-RED is a cool graphical tool to define data paths and integrations. Database, web server and other services on-board makes it possible to implement stand-alone applications without mandatory need for other back-end or cloud at all.

Conduit has compact form factor with dimensions of 13 x 10 x 4,5cm. Two expansion slots together with integrated cellular data modem, GPS, Ethernet, and USB host makes it versatile for many different kind of IOT applications. Initial set of mCard expansion cards include RS-232/485, GPIO and LoRa RF. The USB host port enables use of Wifi, Bluetooth, BLE and other dongles as well as external storage and extended connectivity.

Multitech provides readily available integration with IBM Bluemix via IOT Foundation using MQTT protocol with secure connectivity and safe data storage. Bluemix is handy environment for rapid prototyping and integrations, spanning up to production use as well. Node-RED is one of the programming options in Bluemix as well.

mDot is a new intelligent RF module from Multitech. It is available in two versions; Xbee compatible form factor with pin headers, or surface mount PCB. LoRa variant of mDot contains LoRa RF chip from Semtech and STM32 microcontroller from ST for application software. The controller is freely programmable by user and there is no need for additional MCU. This makes it cost efficient alternative, as a comparison; Microchip's LoRa module has a network controller inside, but requires an external application controller outside, which affects the overall BOM cost structure of a device.

In ARM mbed Ecosystem, Multitech has provided mDot platform support for mbed environment. Free and open source software stack is available via mbed developer site. Free mbed IDE, compiler and repository in cloud makes it easy and straightforward to start development. For more demanding development there is option to deploy the build environment in Eclipse IDE.

With free mDot library and LoRaMAC implementation, plug & play connectivity with Conduit is provided. Multitech provides number of readily available example implementations in mbed team repository which makes it easy to start development. LoRaMAC and mbed can be used with other processors as well, not limited to Multitech modules, like I did with Freescale FRDM-LK25Z board reported in my previous blog posting.

Conlusions
With readily available mbed and Bluemix integration, developer can set up the full chain from device to cloud in matter of hours, not days or weeks or months. This is definitely a significant productivity improvement over the traditional approach.

From now on, I'd feel it silly to start implementing device side code from scratch, manually installing back-end services a top of virtual server, and so on.  When teams can focus on what brings the true value to the customer or user, they are able to fail fast - not after months of development - to get immediate feedback whether the idea works or not. As an investor I'd love this approach.

That's the great value prop of the new IOT era - make me able to fail faster than ever before.

Real-life performance of the LoRa radio

Numbers put in datasheet is one thing, but experimenting the performance in real environment gives you the confidence. According to our experiments, LoRa really does outperform other competing RF technologies.

Today I performed some RF link length and performance testing in customers premises in production facilities. The purpose was to detect the limits of different frequencies and radio technologies commonly used in Wireless Sensor Networks, which means low power and low cost. Testing was limited to license-free IMS bands with transmit power within legal limits. Protocol issues were not covered in this experiment since the purpose was to set theoretical limits of any radio.

National Instruments Finland kindly supported us by supplying necessary wireless measurement instruments: NI PXI FlexRIO SDR (Software Defined Radio) which acted as a base station, and NI USRP (Universal Software Radio Peripheral) which was used as mobile station together with laptop running LabVIEW.

RF testing ongoing: measurement man at the left,
USRP in the middle, and PXI FlexRIO on the right.

The test environment consist of 160m long warehouse with interconnected manufacturing and office spaces. All in all rather complex building with many concrete walls, number of metal plated walls, metal fire doors, and plenty of metal structures inside. Mobile phones didn't work in many spots and Wifi had very limited coverage. Definitely difficult environment for any radio, just like real industrial deployment sites tends to be.

Typical narrowband tranceiver have receiving sensitivity of -110dBm, thus we decided to map the border where typical radio can not detect signal from noise. Test results of 434MHz, 868MHz and 2.4 GHz didn't surprised much. 2.4 GHz achieved 80m link length with direct line of sights. It couldn't penetrate through the first concrete wall.

434 and 868 MHz had very similar performance to each other. Almost the whole building complex was covered with recognizable signal. Only at the other end of the building in a completely metal covered hall with tiny windows in doors the signal was completely lost.  434 MHz benefits from open doors, even if they are not within the direct line in between transmitter and receivers. This indicates the lower frequency reflects from structures better and can bounce within the labyrinth, whereas the higher frequency tends to travel more straightforward though obstacles. When fire doors were closed, there was no significant difference in performance.

Then we compared the results of narrowband RF with spread spectrum LoRa radio. We changed from NI equipment to actual LoRa hardware, as generating the spread spectrum signal with software radio would be way too complex and effort consuming exercise for the purpose of this test. ARM mbed-enabled SX1276 LoRa development board from Semtech and FRDM-KL25Z MCU development board from Freescale was used instead.

LoRa RF test equipment for 434 and 868 MHz with battery pack.

In this experiment, we did not only measured carrier signal strength, but two-way packet communication over LoRaMac was used. Other radio unit was located in the same spot with the original base station. With this setup, we couldn't identify the limits of the connectivity, as we got packets through in all over the building, even in most difficult locations.

We went event to a bomb shelter in the basement of the office wing, with heavy steel-reinforced concrete walls and blast doors. There was no problems with signal when doors were closed. We event put the radio into a all-metal locker in the bomb shelter and locked the door. Still the signal passed happily, obviously through the small ventilation holes of the locker, and through all the concrete walls up to ground and into next wing of the building.

Really incredible result!

At last we moved the base station into most distant location within the building at the end of the warehouse hall. Now we managed to create challenging enough conditions for the radio. To block the signal, several concrete walls, metal fire doors and dozen or so metallic warehouse shelves were needed. Performance of 434MHz and 868MHz Lora was similar to each other, just like recognized in narrowband Sub-GHz tests.

The conclusion: We did not quite reach the promised 150-160 dB link budget advertised by LoRa datasheets and marketing material. However, we did got 145 dB link budget in a real and challenging environment. It really does outperform any competing technologies, not only in paper but in practice as well, with actual two-way data link established.

The test was performed with two LoRa end-nodes. I'm really waiting for a possibility to repeat the experiment with real LoRa-gateway having a LoRa concentrator chip in place. LoRa Alliance was publish at the beginning of January 2015, thus it is still pretty new technology.

Internet of Testing

Internet of Testing is all about productivity improvement. Market leading test and measurement technology from NI integrated with leading Cloud technology from IBM makes at all possible.

"LabVIEW - Improving the Productivity of Engineers and Scientists". is the main value proposition of National Instruments, as stated on their web site. LabVIEW is great tool for test and measurement of all kinds of physical phenomena. Robustness of the technology makes it good for most demanding live monitoring and automation control applications.

The real value comes from the high productivity of software development with graphical LabVIEW programming language. Graphical presentation makes LabVIEW program easy and intuitive to understand, but the value lies in the great amount of readily available mathematical algorithms, instrument drivers, communication interfaces, and user interface elements.

LabVIEW program can run in a PC (Win, Mac, Linux) or in a measurement instrument (RT-Target) like myRIO, CompactRIO,SingleBoard RIO, System-on-Module RIO, etc.  However, so far LabVIEW has provided limited support for remote operations and distributed architecture. But now the situation has changed.

Internet of Things Foundation is a IBM cloud-hosted service for collecting, storing, and integrating data of Things. IoT Foundation provides ready and direct integration to Bluemix, it's like one of the Bluemix APIs. When talking of Bluemix, we're yet again talking about productivity improvement, which is the main value proposition of PaaS (Platform as a Service).

When combining these two technologies, we get productivity square two. And that's the big thing!

LabVIEW recipe for IOT Foundation

Espotel has contributed my work to the open source community. It's a recipe how to connect any LabVIEW program, running either in a PC or in a measurement instrument, to IOT Foundation cloud fast and easily. It's a simple LabVIEW library which can be included in any LabVIEW project.

Example usage of the LabVIEW library for IOT Foundation

IOT Foundation uses MQTT for data transfer. It's fast, reliable, lightweight and secure messaging protocol intended for M2M and IoT applications. The LabVIEW library consists of three main elements:

• Open MQTT connection to IOT Foundation
• Publish (transfer) data over MQTT to IOT Foundation
• Close MQTT connection to IOT Foundation

The library contains one more element for reading device credentials from a file. IOT Foundation provides secure device registration, authentication and data transfer mechanism, based on credentials. Storing credentials is a file makes it possible to use the library in any stand-alone instruments without local user interface.


Applications:

• Remote real-time LabVIEW or HTML user interfaces
• Remote measurement and distributed testing
• Condition monitoring

IoT Ecosystem Game

Internet of Things is changing the world. Not by what we do, but how we do things. This affects individuals, organizations and business ecosystems.

Until now, we have seen ecosystems dominated by a single companies. Let's take Apple as an example. In specific consumer product segments, Apple has ruled the whole value chain from hardware via software to markets and distribution channel. With the model Apple has succeeded to collect 80% of profits of smart phone industry, with only 18% market share.

IoT however is way too diverse for any single company to dominate. Applications vary from hen houses to connected cars, from thermostats to medical instruments. Just like technical architectures are changed from M2M verticals to horizontal layers of IoT, are businesses forced to co-operate with partners and competitors.

M2M vs IOT architecture.

Connected devices is nothing new, M2M has existed from 10 to 20 years already. However, M2M  tends to be like vertical silos, application specific end-to-end solution with limited expandability. IoT as opposite is more like Internet architecture in general, horizontal layers without predefined purpose for any specific function.

Changes in connectivity architectures reflects to ecosystems. A healthy IoT ecosystem has different players for different horizontal players, and preferably many of them. A good example of IoT ecosystem is build around ARM and IBM. ARM provides technology for Things and  IBM for Internet, making it Internet of Things.

ARM embed and IBM cloud offering are really a winning combo. ARM has the strongest ecosystem of silicon vendors. IBM with it's new cloud offering and partnership with Apple, ARM, Semtech, and many more has really gained reputation. This heterogeneous and loosely linked ecosystem has no single point of failure.

There is no ring to rule them all, and there is always room for new trials. That's the only way how the technology can go further in large scale, the law of natural selection applies in technolofy as well.

Just recently Intel announced a new IoT platform, partnering with Accenture, Capgemini, HCL, NTT Data, Tata Consultancy and Wipro. Basically, that's a single silicon vendor with bunch of consultants. Doesn't sounds like a healthy ecosystem. I expressed my thoughts  about the Intel Edison/Quark technology already a year ago. The technology is the basis of this new alliance, which really doesn't convince me.

Node-RED for Home Automation

Node-RED is a great tool for creating graphical data stream integration and processing flows. Now Node-RED is even better suitable for home automation, as support for multiple different wireless sensors is added via Tellstick Duo.

Yesterday I started to prepare a demonstration for a local Node.js meetup in Helsinki. Node-RED is built a top of Node.js, thus it is natural topic for a presentation in the meet-up. Meanwhile preparing the demonstration, I ended up creating an input node into Node-RED for Tellstick Duo. It is now contributed to the project.

The node is available in npm and github with name node-red-contrib-tellstick.
More detailed information is available on my web site: http://ala-paavola.fi/Node-RED

Node-RED with tellstick input node.

Tellstick Duo is USB-connected 433MHz RF transmitter and receiver from Telldus Technologies in Sweden. It supports wide range of commercially available sensors and devices from different vendors.

Node-RED was initially created by IBM Emerging Technologies at IBM Hursley lab, Winchester UK. It was released as an open source project and is still actively maintained and supported by IBM. It's one of the key assets in IBM Bluemix portfolio.

Couple of weeks ago I met one of the initial creators of the software, Dave Conway-Jones (@ceejay). His answer to my question why did they released it as open source in the first place was something like: "We tough it's so cool that it would be a crime against humanity not to publish it to the whole world." Well, perhaps Dave didn't expressed it exactly like that, but that's how I feel it.

Node-RED is really gaining momentum at the moment. More and more manufacturers are including it in their products, Multitech Conduit IoT Gateway as an example.

More and more devices are supported by Node-RED, Philips Hue for example.
A friend of mine, a system operator, created a build health status indicator with help of Node-Red and Hue. He integrated Node-RED into their company continuous integration tool chain, and now everybody in the office see what's the status of the build. If someone breaks the build, server room neighbourhood is immediately glowing red...

LoRa in constructed environment

Suddenly LoRa has became one of the hottest technologies in the Internet of Things domain. The number of new customer cases we see in our company is increasing on a daily basis. But where's the beef?

There are two main use cases where LoRa is strong:
- Wide area wireless sensor network (W-WSN)
- Factory (or any facility) area netwok (FAN)

In W-WSN applications, individual diameter of individual LoRa cells may vary from 2 to 20 kilometers. This makes it possible to collect data from many sensors into single gateway for upstream via wired or wireless connections (3G/4G data mode). This is the modem killer scenario explained in previous posting.

Factory area network with star-topology.

FAN is perhaps more common use case for LoRa. Facility can be anything including factory, refinery, warehouse, seaport, shopping center, or office block, and all other cases where mainstream technologies like WiFi, Bluetooth, Zigbee, and other 2.4 GHz RF can't do the job without unreasonable number of access points or complex multi-hop routing algorithms and routing node.

LoRa modulation has certain characteristics which make it suitable for difficult constructed environments like a factory.

Aa a rule of thumb: the lower the frequence the longer the distance, or better peneration. Reduction from 2.4 GHz to Sub-GHz frequencies alone gives significant improvement. The CSS modulation of LoRa makes it possible to detect signals 20dB below the noise floor, yet giving improvement over traditional narrow-band Sub-GHz radios.

Multipath propagation

Multipath fading is a common problem in constructed environment. Signal may travel via multiple different routes due to reflections from different surfaces. It's like echo on a railway station making it very difficult to understand announcements given by loudspeakers. In radio technology, multipath propagation may cause signal amplification or attenuation with short displacement of the receiver.

Up-chirp, increasing frequency sweep in time domain.

Different frequencies have different reflection signature. Chirp Spread Spectrum (CSS) uses frequency sweeps to carry information. During the sweep, some frequency may attenuate, whereas some other frequency may be amplified. All in all, detection of signal in receiver side is very reliable. Consider the railway station example. If audio frequency sweeps - chirps - are broadcasted from loudspeakers, human can easily recognize whether the individual sweep is going from low to high (up-chirp) or from high to low (down-chirp), even if significant echo takes place.

Frequency also affects signal penetration. Due to various reasons, certain frequencies may penetrate better than others. By spreading the signal to wider bandwidth, we increase the probability that some signal gets through. According to our experiments, LoRa has been the only commonly available IoT RF technology, which can deliver data from inside a closed metallic storage container to outside world.