Sigfox is an LPWA technology developed by Siggox in France.
Sigfox is an IoT communications technology developed by Sigfox in France and is one of lpWA as well as LoRaWAN, LTE-M, NB-IoT, etc. Sigfox carriers, like cellular, need to develop infrastructure such as base stations, but what’s interesting is that only one carrier in a country is allowed to offer Sigfox services.
In Japan, Kyocera Communication Systems (KCCS) provides Sigfox, and KCCS is the only Sigfox carrier in Japan.
LPWA Comparisons
LPWA, including Sigfox, has the following characteristics:
Sigfox utilizes unlicensed 920MHz band same as LoRaWAN in Japan and doesn’t focus on communication speed but covers up to several tens of km at a single base station.
Sigfox available areas are rapidly expanding both in Japan and global
Sigfox is a new company founded in 2009, but the Sigfox service area is expanding rapidly around the world. For example, in Japan, KCCS launched its service in 2017, but one year after the launch of the service, the area expanded to 50% population coverage, and as of 2019, the population coverage is more than 95%. It’s really amazing that the coverage area has been expanded just for 2 years.
If you look around the world, Sigfox’s service area is expanding around the world as well.
As of 2019, the service has been launched in more than 60 countries, and the area is expected to grow in the future.
Features of Sigfox
Sigfox service is provided by 3 groups, device partners who provide IoT devices such as chips and modules, network provider like KCCS, and application partners who provide apps and platforms.
There are four technical features of Sigfox
Only 200KHz in narrow band
Sigfox can operate at a very narrow bandwidth of 200 KHz, one connection utilized small bandwidth 100MHz and it can communicate at 100-600 bps. It could be transmit long distance and resistant to noise.
Lightweight protocol saves power
Sigfox uses a very light protocol to communicate with small messages, which can significantly reduce power consumption, thereby greatly extending the battery life of IoT devices.
Data size is around 20 bytes
Sigfox sends up to 12 bytes of messages over a two-second time. For 12 bytes, it can be sent as very small data, which is only 26 byte, including headers, etc. The downlink can send messages of up to 8 bytes.
Use multiple base stations to send data over a star network
Sigfox’s network is configured as follows: The device is not attached to a base station somewhere like cellular, but broadcasts to multiple base stations when sending a message. On average, there are about three base stations that receive messages. In addition, when sending a message, always repeat the transmission three times, and change the frequency to be sent in each.
Messages received at each base station are consolidated into a single cloud, where they are aggregated into a single message and sent to the contractor’s IT center.
Sending a message to the device is based on a request from the device. In other words, it is characterized by the ability to receive messages on the timing that the device likes. When the subscriber’s IT center receives an incoming request message from the device, the IT center sends the message and delivers the message from a specific base station to the device.
Sigfox has a communication limit of up to 140 messages per day.
Sigfox Use Cases
There are already many use cases using Sigfox, like other LPWA, such as LoRaWAN and LTE-M.
Water meter reading
In the past, water meters were checked visually by visiting one house at a time via hand, but by using a water meter equipped with Sigfox, it is possible to automatically send the necessary data to the center, which eliminates the need for visits. Because the data being sent is very small, for example, it is possible to significantly reduce power consumption even when sending water usage data twice a day, and the battery does not need to be replaced for several years. In addition, by sending data directly to the cloud, it is easier to graph and analyze data, and it is easier to perform detailed management than ever before.
Use in Agriculture
Agriculture is an easy area to take advantage of IoT, and many use cases for agriculture have been developed in Sigfox.
For example, it is possible to collect a large amount of information, such as the amount of CO2 and soil information, as well as temperature and humidity in a vinyl house, aggregate it into the cloud using Sigfox, and display the results of the analysis at hand. All of this has been done manually so far, so it was necessary to move to the site and make measurements every time it was measured, but Sigfox makes it possible to make operations more efficient.
Disaster prevention
In some cases, Sigfox is used to monitor water levels and rainfall in rivers and ponds. Data collected by water level and rainfall monitoring systems can be sent to the cloud via Sigfox to alert if water level or rainfall exceeds the threshold. There are hundreds of thousands of hazardous areas in Japan, and it is expensive to deploy and operate a monitoring system in each of them, but Sigfox’s low cost of running and power saving can significantly reduce costs.
Prospects for the future
Sigfox is a new technology that began in 2017, but in 2019, the population coverage has exceeded 95%, and it is entering a phase that is becoming more and more popular. Sigfox does not support mobility, so it is difficult to deal with moving things, but it is expected that applications such as logistics management, parking lot management, crime prevention, etc. will expand one after another, including the use of previous agriculture, disaster prevention, various meters, taking advantage of the features of low running costs and power saving.
