Lorawan, which I can't hear now, explains the differences from other LPWA

LPWA (Low Power Wide Area), low power consumption and long -distance communication technology that is active in the field of IoT.There are various communication standards such as LTE-M, NB-Iot, SIGFOX, LORA, and ZETA.In this paper, we look back on the characteristics and differences of these communication technology, which has been attracting attention since the dawn of IoT.In the latter half, focus on Lorawan in terms of practicality, and explain its characteristics and use cases.

table of contents

What is LPWA?

LPWA features

LPWA is an abbreviation of Low Power Wide Area and is a general term for communication technology featuring low power consumption and long -range communication.There is no communication standard called LPWA itself.

LPWA communication is basically low -speed, and the communication speed is more than 100 kbps (bit per second *).It is used for sending and receiving sensor data, simple machine control signal communication, and ultra -high -compression images (still images).For communication speeds from 100Kbps to 10Mbps for the same purpose, there are LTE, 3G, Wi-SUN, and Bluetooth.

* 1kbps: The information of 1000 -bit can be transferred per second.

LPWA advantages / disadvantages

LPWA, as the name implies, is "low power consumption" and "long -distance communication" (Wide Area).

低消費電力

Depending on how frequently you send data from the terminal (number of communications), basically, two AA batteries can continue to run for one year.In addition, by using technology such as solar panels, it can work semi -permanently.

The reasons why LPWA is power saving is the following three technologies.

On the other hand, LPWA communication specialized in power saving has a disadvantage.That is, the number of data transmitted and the amount of communication are limited.

For example, it is not suitable for real -time communication, such as sending data once per minute.To the last, the data in the state of the sensor is sent at a certain interval (once every 30 minutes or once in an hour), or the sensor is evoked to check the condition.It is suitable for applications.

In addition, there is a limit on the functions that can be implemented in the control of the terminal (downward communication).Alternatively, there is a standard that does not allow downward communication in the first place.

長距離通信

Although LPWA is a long -distance communication, the distance that can be actually communicated depends greatly on the location and outlook (presence or absence of shields).

Further, in the metal housing or near the metal, the communication distance is shorter due to the disturbed or blocked radio waves.Or sometimes you can't communicate.

From the above, when considering the installation of sensors and base stations, it is important to check in detail the installation environment and the outlook from the base station to the location of the terminal.

Also, as described later, the communication distance varies greatly depending on the communication standard in LPWA (there is a distance of 1 km to 100 km according to conditions and standard differences).

The following three technologies are the reasons why LPWA is long -distance communication.

However, the above advantages can also be a disadvantage if you turn it over.For example, LPWA has a slower design than other general communication methods (Wi-Fi, LTE, etc.) to ensure reliable communication in a wide area.In addition, in order to ensure sufficient communication distance, sufficient tuning, such as the installation design of base stations and the antenna design, may be required.

LPWA type

ライセンスバンド型/アンライセンスバンド型

There are two types of LPWA communication standards: a licensed band (a bandwidth that requires a license) and an unlicensed band (a bandwidth that does not require a license).

The license band is a bandwidth that mobile carriers (docomo, KDDI, Softbank, Rakuten) can be used by the Ministry of Internal Affairs and Communications..1GHz, 1.5GHz, 800MHz, 900MHz, etc. are applicable.

On the other hand, the unlicensed band can be used freely by any certified device.5GHz, 2.4GHz, 920MHz, 430MHz, etc. are available.

LPWA communication standards that use the license band include LTE-M and NB-Iot.The unlicensed band includes Sigfox, Eltres, Lora, ZETA, Wi-SUN.

サービス提供型／基地局提供型

In addition, LPWA is in each communication standard, users can only purchase sensors, and the communication infrastructure itself is a "communication service type", which is provided by the business operator, and the "base station" can be installed by the base station.It is divided into two parts: a station -provided type.

The "communication service type" has the advantage that business operators can easily use LPWA communication services because they do not need to operate base stations on their own.However, it is necessary to note that the communication service may not be available in areas where the network is not developed (for example, outdoor use scenes far away from the city center).

On the other hand, in the case of "base station -provided type", it does not require communication costs to be used on its own by becoming an "telecommunications carrier" that operates a base station.It is also possible to make money by providing services.In other words, you can use base stations freely with almost the same feeling as "large Wi-Fi".

However, although the "base station -provided type" has a high degree of freedom in installation and construction, the maintenance and operation of the base station must be performed by the user himself, which requires some specialty.Therefore, while the base station itself is owned by local governments and companies, the specific and specialized tasks are outsourced to external telecommunications carriers (indicating the "agricultural" model above.)

Various communication standards

Here, we will introduce the characteristics of various communication standards of LPWA.

LTE-M

Has the maximum communication speed among LPWA (up to 1Mbps).It can also be used for files with large images and capacity.It is a licensed band/service -provided LPWA standard, and can use communication services anywhere in the mobile call area.

NB-IoT

Like LTE-M, it is a licensed band/service-provided LPWA standard, and can be used anywhere in a mobile call area.The communication speed is 100kbps, which is used for data transmission and reception with a smaller capacity than LTE-M.

For example, it is suitable for applications where terminals and networks are connected at a low frequency, such as a water level sensor in a river.At present (November 2021), only SoftBank provides services using NB-Iot among mobile carriers.

Sigfox

LPWA service provided by France SIGFOX.In Japan, 920MHz is used for the frequency band of the unlicensed band.Licensing communication services is said to be only one company, and Kyocera Communication Systems is in charge in Japan.

Businesses do not need to set up base stations on their own, and can easily start using communication services.The communication speed is as small as 100bps, but the reach is 10 km or more, and it is expected to be used over a wide range of smart city.

ELTRES

LPWA communication service developed by Sony.Like SIGFOX, it is an assembly band type/service provided type.Users can purchase a compatible terminal and pay the monthly usage fee.

The maximum communication distance is 100 km, the most wide area of the LPWA communication standards.It also supports the use of "high -speed mobile body" (such as Shinkansen), and since it uses synchronous communication of GNSS (Pan Earth Machine Service System), it is also excellent in acquiring high -precision location information.ing.

However, it does not support downward communication and cannot be used for indoor use because it uses GNSS synchronous communication.

ZETA

LPWA wireless communication standard developed by Zifisense in China.Because it is a later technology, it covers the drawbacks of existing LPWA technology that is difficult to connect in an environment with poor visibility.That is, it supports multi -stage communication and two -way communications that use multi -hop (relay station).The reach is 10 km.

Like LORA, it is an assembly band type/base station provided.Products and services have been released from partner companies participating in ZETA Alliance.

Wi-SUN

Abbreviation for Wireless Smart Utility Network.Like ZETA, it is a type of assembly band/base station provided.The 920MHz band is used in Japan.

Compared to other LPWA standards, the communication speed and the communication distance are not so large, but it also has a characteristic that it is strong and easy to connect with obstacles because it supports multi -hop communication.It is popular as smart meters such as electricity and gas and networks for home HEMS.

Wi-Fi HaLow

"Wi-Fi Halow" is the IEEE standard 802.Wireless communication technology specified as 11Ah.In Japan, the frequency of the 920MHz band is used.A certification program started in November 2021.Unlicen band type/base station provided type.

Wi-Fi Halow is a wireless communication technology that has both Wi-Fi and LPWA characteristics.Up to 1km wide area communication is possible, and depending on the distance, it also supports data communication with large capacity such as images and videos.Because it is an international IP -based standard, it is an international IP -based standard, so you do not need a dedicated network server, and you can easily build a network environment using various devices and apps based on IP -based.。

About lorawan

From now on, we will explain in detail the features and use cases of Lorawan, a type of LPWA technology.

LORA features

LORA is a frequency modulation method for LPWA wireless communication developed by Semtech, a major US semiconductor manufacturer (LORA itself is not a wireless communication standard, but only a frequency modulation method).

License band type/base station provided type.In Japan, the 920 MHz band (920-928MHz) is adopted, and businesses can set up base stations on their own and introduce LORA wireless networks.

Difference between Lora and Lorawan

LORAWAN is a specification (protocol) that uses a LORA modulation method and defines communication and control methods from devices to gateway.However, depending on the context, Lora may be called Lorawan.

LORAWAN has been formulated and opened as an open source, formulating the specifications in an open organization called "Lora Alliance".For products that comply with specifications, mutual communication is possible for different vendors.There is a Lora Alliance authentication system, and LORAWAN -compatible devices ensure interconnection.

Lora Alliance has more than 400 companies all over the world, and it is one of the benefits of Lorawan that it can be connected immediately to the equipment of those manufacturers.

General Lorawan system

The system that uses Lorawan is mainly composed of sensors, gateway (base station), network server, and cloud services (applications).Users need to prepare all of these functions and build a system.

As shown in the figure above, the data obtained by the sensor is collected to the gateway by Lorawan communication.Furthermore, the data is connected to the network server by communication such as LTE/WAN/VPN.The network server can be connected to each sensor via the gateway, and can be managed, data rates, and channel allocation.

The network server can be used in various advantages of the data collected from the sensor by linking external cloud services and the Internet.

In addition, it is effective to build a secure communication environment from gateway to external cloud services using the IoT platform.See the following articles for this.

Lorawan issues

The biggest feature of Lorawan is that businesses can operate base stations on their own.In other words, it means that if you own a base station, you can create an IoT communication service, so LORAWAN should be a priming for the spread of IoT.It was done.

However, in fact, enormous investment is required to register as an telecommunications carrier and operate thousands of base stations.In the current situation where devices are not as widespread as mobile phones, the operation is still quite difficult.

It was also expected that 100 km wide -area communication would be possible if a base station was installed in a place with good visibility, such as on the mountains.However, in fact, even if a base station is set up in the mountains, the permission application, construction cost, and maintenance costs for that will be high.In addition, places with a little poor outlook cannot be connected, so it does not work.

What is expected by Lorawan

In other words, LORAWAN's task is that excessive expectations such as "can do anything (unconditionally)" rather than Lorawan's technology and potential itself is not understood. It is in.

So what is LORAWAN's strength?

屋内・屋外問わず、数百～数千のセンサーを手軽に接続

Lorawan is not suitable for large amounts of data transmission and reception, unlike LTE-M (video, audio, etc. are difficult).

Also, as in SIGFOX, we are not good at wide -area communication of 10 km or more.When installing at a high place, if the outlook is good, it may fly more than 10 km, but a specialized design and installation know -how of the base station is required.

However, if it is about 1 km, it can be easily connected regardless of indoors or outdoors.In fact, this is the strength of Lorawan.

For example, in an environment where many sensors are placed in large buildings, such as buildings, large stores, logistics warehouses, and factories, even without a very careful radio simulation or actual measurement test, the base station (gateway).Just put the sensor for the time being, you can easily cover the whole network.

In addition, being able to hold the base station (gateway) on its own means that you can freely place the base station where you like.For example, if you want to install a sensor in hundreds of refrigerators in a large store and manage the temperature.The connection is greatly dependent on the location of the base station.

At this time, if the connection of certain places is poor while using the communication services of other companies, what can be done as a business operator is limited.However, in the case of Lorawan, the location of the base station can be freely adjusted, so that the connection can be ensured.

オープンな技術仕様により、相互接続性が担保される

Semtech, who developed the base technology of Lorawan, offers only a communication chip that assembles the LORA modulation method.Other sensors, communication modules, base stations (gateway), clouds, apps, etc. are all open, and each vendor can be developed freely.

Therefore, it is easy to ensure the interconnecting properties between devices and layers (sensor ⇔ communication modules ⇔ gateway ⇔ app), and can be replaced in an emergency.

For example, a company called A used a manufacturer B, Lorawan Gateway, but stopped providing it when B was.However, even in this case, the specifications of the technology required for Lorawan are all open to the Eco System called Lora Alliance, so business A can easily switch to other manufacturers.。

Lorawan use case [case]

The following are use cases based on examples that are actually operated and have found results.

水田の水管理

The above figure is an overview of the case of "water management of paddy fields".In the past, farmers have visited vast rice fields and measured the water level and water temperature.However, by installing a sensor and visualizing the state, it is possible to reduce the effort to go to paddy fields.

In the case of farmland, there is a problem that it is difficult to secure power supply to the gateway (base station).Can do.

In addition, Lorawan has been developed with downlink communication (downlink communication) in mind, and is suitable for control of various agricultural equipment (for example, in the case of the figure above, automatic water valve).

In such a smart agriculture field, many sensors are connected.Therefore, in the billing model (service -provided type) for each sensor, the management of contracts, payments, and communication costs becomes complicated.

If you use a base station -provided LPWA like Lorawan, you can simplify the fee structure.Furthermore, while starting from a single farmer, it can be scaled up later and shifted to operations in collaboration with local governments and JA (agricultural cooperatives).

In addition, as described in the first half of the article, it is possible for local governments to operate the base station.In this case, each farmer can focus only on the management of sensors installed on their own farmland and the use of data.

冷凍/冷蔵庫の温度管理

The revised Food Sanitation Law, which was passed in June 2018, has mandatory food operators to provide hygiene management procedures in accordance with HACCP.Therefore, the number of voices that want to efficiently implement and operate the temperature control during food storage, which is one of the hygiene management process, is increasing.

By using LORAWAN, the temperature can be remotely monitored from hundreds of freezers, refrigerators, and sensors attached to a cold case in the shopping mall, and can be recorded automatically.

For example, about three times a day, the person in charge looked at the thermometer and wrote the numbers on paper, but just attached the Lorawan sensor to the refrigerator with a magnet, and once an hour.It will be possible to automatically collect and manage temperature data by frequent and stable.

The gateway can be connected to hundreds of sensors on the floor, for example, on a refrigerator located in the center of the building, such as on a refrigerator.

In fact, the effects of artificial reduction of description work in paper ledger, elimination of refrigerator patrol work, omission of temperature records, avoidance of entry mistakes, and eliminating paper ledger for recording.

In addition, there is a method of automatically collecting data with a wired network in such an indoor IoT case.However, in that case, the cost of the introduction of several million yen will be charged for wiring work.On the other hand, LORAWAN's wireless communication can easily collect data by simply attaching the sensor to the target device, so the hurdle of introduction can be considerably reduced.

ビルや店舗の管理

Lorawan is also used as a communication technology for visualizing the operation status and air environment of building equipment, such as commercial facilities and hotels.Specifically, it is possible to visualize the operation status of each equipment such as outdoor units, the temperature of the tenant, and the CO2 environment.

As a result, proposals and execution of prior equipment maintenance plan can be proposed and executed based on the operation status.In addition, it is possible to understand the optimal timing that should be ventilated from the CO2 concentration data, grasp the temperature and humidity on the floor, and provide a comfortable environment to customers such as shoppers and guests.。

Similar to the temperature control of the freezing and refrigerator, Lorawan is suitable for indoor use, and it is a great advantage that you can easily attach base stations and sensors.

How to actually use Lorawan?[Practice]

From the above, I think that you can understand the characteristics and practicality of Lorawan to some extent.However, many people don't know what to do when they use it.In fact, the following processes are required.

Although Lorawan is characterized by its simple connection, it takes some specialties to proceed with these processes from zero.

Internet Initiative Co., Ltd. (IIJ) comprehensively supports all the processes required for the use of Lorawan.In addition, partial support is provided, such as (1) lending and sales of radio wave measurement devices and (2) radio wave propagation simulation.

If you are considering the introduction of Lorawan, please contact us through the following sites.

Also, from the entire IoT system from sensors to applications (clouds), Lorawan communication from the sensor to the gateway is only a part of the function.In the use of IoT, it is desirable to examine the purpose and the overall picture of the system, and to examine individual functions in detail.

Therefore, IIJ comprehensively supports all layers such as sensors, gateway, IoT platforms, and applications, and also provides package solutions specializing in fields such as manufacturing, agriculture, and smart homes.See the link below for details.

[Related links] ・ IIJ IoT Service ・ IIJ Industry IoT Secure Mote Management/Machinery ・ IIJ Industry IoT Security Mote Management/Factory

Technology and scientific writer.Master (applied chemistry).After working for an oil manufacturer, he has been active as a writer since 2017.He also contributes to scientific magazines.