What is LPWAN and how does it work?
LPWAN quite simple. A sensor, with long runtimes (of 2 to 10 years), records physical parameters such as distance or temperature etc. and sends the measured values to a cloud. The measured values then appear on your screen.
LPWAN, LoRa, NB-IoT and Co. – What’s it all about?
Basically, LPWAN stands for Low Power Wide Area Network and refers to a sensor network in which several sensors operate in a network – similar to how several computers or devices are integrated in a WLAN or LAN. The big difference in LPWAN applications is the energy efficiency of the devices (as the name Low Power already suggests). In contrast to other networks, such as WLAN, LPWAN networks are not suitable for sending large amounts of data; the transmission rate is limited. On the other hand, much larger ranges and much longer battery runtimes are achievable.
What are LoRa® , NB-IoT and LTE-CAT-M1? These terms basically denote communication standards – similar to how Bluetooth and WLAN differ, for example. These LPWAN technologies (LoRa® , NB-IoT and LTE-CAT-M1) use low frequency bands to achieve long ranges. Genrally there are a couple of protols available. Some are cellular based others use their own infrastructure.
LoRaWAN defines the standard communication protocol and system architecture for the network, while LoRa® describes the physical layer that enables the „long range“ communication link. The protocol and network architecture have the greatest impact in determining a node’s battery life, network capacity, quality of service, security, and the variety of applications served by the network. This technology uses so-called gateways to transmit the data from the sensor to the Internet. A gateway is similar to a WLAN router in a normal household. A sensor sends information to all gateways available, which translates the information and sends the data via a network server to the Internet, where the data can be further processed – analogous to how a smartphone communicates with a router. Favorable locations are high buildings. How many gateways you need depends on individual circumstances. It is estimated that with LoRa® realistic ranges of 2 km in urban areas up to 15 km in rural areas are achievable. In our Yamori space mission we could achieve about 700 kilometers range in free space. The range depends largely on the locations of the gateways and sensors.
This technology is based on the existing mobile network and uses cell towers as gateways or routers. This means that each sensor has a special sim card from a mobile communications provider. With some providers, the data volume is already reserved for 10 years at a low prepaid price. NB-IoT uses frequency bands of the LTE spectrum and is optimized for energy efficiency, unlike the LTE you may know from your smartphone. For NB-IoT, you don’t need infrastructure in the form of gateways to implement applications. You can jump right in.
No technology without competition. LTE-CAT-M1, just like NB-IoT, uses the existing mobile communications infrastructure as gateways. The two technologies are not available in parallel in all countries. Some countries rely on LTE-CAT-M1, others on NB-IoT, and some on both standards. We do not know which will prevail in the medium and long term. It may well be that the three technologies listed coexist, since they do differ in details.
What is the difference
LoRa® is one of the most energy-saving technologies, i.e. with the same number of transmissions per day, the battery lasts the longest. In return, much smaller amounts of data can be transmitted. NB-IoT and LTE-CAT-M1 consume more power, but larger amounts of data can be transmitted. This still means that transmitting large amounts of data, such as a video, is not possible, at least in energy-autonomous applications.
An example application
A simple example. Some municipalities have to conduct groundwater measurements on a regular basis. To do this, employees must travel to specific points, measure the level, document it and file it away. Not only does this process cost money, but information can be lost. With an energy-autonomous sensor, the groundwater level can be monitored „continuously.“ The sensor is maintenance-free and, depending on the transmission interval, has a shelf life of 3 to 5 years. For example, our sensors can transmit the current level 12 times a day and measure 24 times with a 5 year life. You can easily see the data on your screen. In addition, the data can be exported and stored automatically. Furthermore, when preset level limits are exceeded, the measurement and transmission rate can be increased and an alarm can also be transmitted, for example via mail or push message. Of course, history data is also clearly displayed on the screen in the form of history graphs. These are the basic functions of a web application. You can find more exciting applications here.
How does the data get to me on the screen?
A good question and technically complex matter, which – fortunately – you don’t need to worry about. You can simply benefit from the finished application. But we don’t want to leave you in the dark either. Here is the basic procedure:
The sensor collects the data (it measures), processes it and sends the data to the gateway or cell tower. There, the data is forwarded to the „Internet.“ The data thus migrates to a cloud. Here, they are stored and further processed and can then be made „visible“ in a web application. This is then the graphical representation of the data that you see on the screen. Our web application runs in the cloud or on a server (like a computer, only not at your location, but at our server location in Germany). This means that to use our web application, you don’t need to install any program and we usually don’t need to interfere with your network infrastructure. The application is a browser application. You can easily access the application with a device of your choice (smartphone, tab, PC, etc.).
What exaclty is Yamori doing?
Yamori makes the development of such solution from the technical side easier than ever before. Based on the Yamori platform, prototypes can be quickly and easily built and the intended applications evaluated. This also closes the gap from prototype to market-ready product. On the basis of a strong network, even complicated solutions can be implemented easily and efficiently.