The Internet of Things is the combination of all current communication technologies with computers and the Internet. The Internet of Things mainly realizes interconnection and communication between things, between people and things, and between animals and things, as well as real-time sharing of environment and information status, and intelligence. The collection, processing, transmission and execution of information technology, that is to say, as long as it involves the application of information technology, it can be included in the scope of the Internet of Things. In the popularization process of the Internet of Things, wireless technology will play an increasingly important role. This article compares three common LPWAN wireless communication technologies (NB-IoT/eMTC/ LoRa ) to explore the respective wireless technologies under the general trend of the Internet of Things. characteristics and application scenarios.
1. NB-IoT
NB-IoT stands for Narrow Band-Internet of Things, and NB-IoT is a technology in the category of Internet of Things. It is an LPWA technology led by Huawei and has become a 3GPP standard. NB-IoT is based on existing cellular network technology and can quickly support industry market demands by upgrading the existing network, becoming the fourth mode on the GUL network. At the same time, NB-IoT also has four major capabilities: wide coverage (can cover underground), long battery life (more than ten years), low cost (less than US$5 per module), and large capacity (a single cell can support 100,000 connections). .
Technical advantages
NB-IoT has four major characteristics: first, wide coverage, which will provide improved indoor coverage. In the same frequency band, NB-IoT has a gain of 20dB compared to the existing network, which is equivalent to increasing the coverage area by 100 times;
Second, it has the ability to support massive connections. One sector of NB-IoT can support 100,000 connections, supporting low latency sensitivity, ultra-low equipment cost, low equipment power consumption and optimized network architecture;
The third is lower power consumption. The standby time of NB-IoT terminal module can be as long as 10 years;
The fourth is lower module cost. Enterprises expect that a single connected module will cost no more than 5 US dollars.
NB-IoT focuses on the Low Power Wide Coverage (LPWA) Internet of Things (IOT) market and is an emerging technology that can be widely used around the world. It has the characteristics of wide coverage, multiple connections, low speed, low cost, low power consumption, and excellent architecture. NB-IoT uses License frequency bands and can be deployed in three ways: in-band, guard band or independent carrier, coexisting with existing networks.
Toepassingsscenario's
NB-IoT is most commonly used in three typical application scenarios: smart water meters, smart parking, and smart pet tracking. In the later planning of NB-IoT, smart bicycles, smart smoke detectors, smart trash cans, smart roads, Smart vending machines, etc.
Challenges faced
First, interoperability and consistency issues. In 2015, major members of NB-IoT, including Vodafone, Ericsson, Telefonica and GSMA, launched simple interoperability and conformance certification trials for NB-IoT devices. Vodafone has also established a dedicated NB-IoT laboratory in Newbury, UK, and will continue to open further laboratory research in Dusseldorf, Germany in the second half of 2016.
Second, deployment and long-term support. The biggest problems with NB-IoT deployment are time and cost. According to Vodafone’s estimates, 85% of enterprise base stations can support NB-IoT and only need to upgrade the software. However, network operators with outdated base stations need to upgrade the hardware. . This will lead to increased costs and time consumption of NB-IoT network construction. Another issue is global M2M roaming. In theory, operators need to support three standards: CAT-M, EC-GSM, NB-IoT, and GPRS. Additionally, endpoints require OTA upgrades to provide security and other upgrades.
Third, applications and business models. In order to establish NB-IoT applications and business models, the mobile communications industry needs to establish a partner ecosystem as soon as possible. For example: Deutsche Telekom has established NB-IoT prototype hubs in Berlin and Krakow, Poland. These hubs are included in incubators to provide developers with a rapid learning environment, stimulate new business model thinking, and shorten the time for product marketization. .
Fourth, competition with LPWAN (Low Power Wide Area Internet of Things) technology. LoRa and Sigfox have proven to be important development technologies. Among them, Sigfox has been put into use in 24 countries, and LoRa continues to be used in the construction of private networks and community networks in some countries. Since NB-IoT will not be deployed on a large scale in the near future, other technology competitors still have the opportunity to determine their market positioning.
Currently, the market popularity of NB-IoT varies between countries. In many countries, potential operators may face strong competition from non-mobile LPWAN networks. For example, in the Netherlands, KPN has established a national LoRa network, in which case it may be less likely to adopt NB-IoT.
Fifth, determine the right market entry strategy. LPWAN applications have the characteristic of sending small data payloads at irregular intervals. Potential users may require more low-value services. In this case, NB-IoT operators need to develop corresponding strategies to cope with such market demand. The main strategies include: establishing a balance between the market and the brand; expanding market share, not limited to traditional M2M business; avoiding cost price wars in the low-end market, focusing on applications that can control price premiums; exploring new business models to create value, Strengthen vertical industry cooperation.
Sixth, the design of pricing plans, mainly IoT data plans. Currently, operators are still trying. For example: Korea Telecom recently launched the nationwide LoRa network and launched 6 data plans, each plan corresponding to data applications using different frequency bands. Its pricing model is: LoRa’s data plan price is only one-tenth of that of LTE-based IoT services. In countries with LoRa or Sigfox businesses, NB-IoT tariffs have to remain within a reasonable competitive range. In the UK, since there is no national LPWAN network, NB-IoT operators will have more room for maneuver when designing their pricing structure.
In addition, issues such as low-speed data transmission, privacy and security, and IT system conversion time will all limit its development.
2. eMTC
LTE-M, or LTE-Machine-to-Machine, is an IoT technology based on LTE evolution. It is called Low-Cost MTC in R12 and LTE enhanced MTC, or eMTC, in R13. It is designed to be based on existing LTE carrier meets the needs of IoT devices.
eMTC is deployed based on cellular networks and supports uplink and downlink peak rates of up to 1Mbps, which is a medium rate for the Internet of Things. Its user equipment can directly access the existing LTE network by supporting 1.4MHz radio frequency and baseband bandwidth. As LTE continues to evolve, the latest eMTC and NBIoT have further optimized system costs, enhanced battery life, and expanded coverage. The most critical capability of eMTC is to support mobility and positioning. The cost is only 25% of the Cat1 chip, and the rate is four times higher than that of GPRS.
Technical advantages
Several of the most important features of narrowband LTE. First, the system complexity is greatly reduced, and the complexity and cost are greatly optimized.
Second, power consumption is extremely reduced and battery life is greatly enhanced.
Third, the network coverage capability has been greatly enhanced.
Fourth, the density of network coverage is enhanced.
eMTC has the four basic capabilities of LPWA: first, wide coverage. In the same frequency band, eMTC has a gain of 15dB compared to the existing network, which greatly improves the deep coverage capability of the LTE network; second, it has the ability to support massive connections. One sector can support nearly 100,000 connections; the third is lower power consumption, the standby time of the eMTC terminal module can be up to 10 years; the fourth is lower module cost, large-scale connections will bring module chip costs has declined rapidly, and the target cost of eMTC chips is around US$1 to US$2.
Toepassingsscenario's
When used in smart logistics, it has the advantages of anti-theft, anti-exchange, real-time temperature sensing, and positionability. It can monitor and locate in real time, record and upload information, and query driving tracks; in smart wearable devices, it can support health monitoring. , video services, data backhaul and positioning; relying on the current cellular network interactive screen, it provides application scenarios including smart charging piles, waiting bags, elevator guards, smart bus stop signs, public bicycle management, etc.
Challenges faced
Analysis of the applicability of eMTC business characteristics to VoLTE business
The typical characteristic difference between eMTC and NB-IoT is that the operating bandwidth of eMTC terminals can reach 1.08MHz, which is much higher than the 200kHz of NB-IoT terminals. Therefore, the peak rate of eMTC terminals is much higher than that of NB-IoT terminals. Based on the above characteristics, the industry generally believes that eMTC technology can provide relatively cheap VoLTE terminal solutions and have better service quality. However, through detailed technical analysis, the actual effect of using eMTC technology to support voice services or provide voice solutions may be difficult to achieve. optimism.
Low power consumption features
In order to be able to provide IoT services in an environment with limited power supply, like NB-IoT, eMTC also takes low power consumption as a system design goal. It is expected to be based on a smaller capacity battery, support terminal maintenance-free for 10 years, and be compatible with NB-IoT. -IoT also uses two power-saving technologies, eDRX (Extended Discontinuous Reception) and PSM (Power Saving Mode). For typical low-frequency IoT services, such as automatic meter reading, since the service frequency is very low, using these two technologies can make the terminal sleep for a long time and only work when data transmission is needed, so it can save a lot of power. , but this good power-saving effect is only effective for lower-frequency services. For VoLTE services, terminals need to often monitor network paging and respond to arriving calls in a timely manner, so the power-saving mechanism of eDRX and PSM technology cannot be used. .
large connection features
The requirements of the Internet of Everything require IoT technology to serve a large number of terminals. To this end, 3GPP has designed two air interface technology optimization solutions: CP (Control Plane) optimization and UP (User Plane) optimization. For IoT services transmitted in small packets, it can save A large amount of air interface signaling improves transmission efficiency. However, for VoLTE voice services, CP and UP optimization solutions cannot be used to increase capacity, so eMTC does not have the ability to increase capacity for VoLTE.
Wide coverage features
Considering that some IoT terminals are often located deep inside buildings, such as water meters, where the signal is often very weak, eMTC has designed repetition technology to enhance coverage. Through the repetition of uplink and downlink wireless signals, it can receive The end accumulates signal energy, thereby enhancing coverage. However, it is precisely due to the repetition of wireless signals that the average service rate is reduced. In other words, this coverage enhancement technology is at the expense of reduced service rate. Therefore, for services such as VoLTE that require a certain rate guarantee, eMTC The coverage enhancement technology brings no benefits.
Low-cost eMTC terminal solution
The low-cost solution for eMTC terminals (chips) mainly includes: smaller working bandwidth. The working bandwidth of eMTC terminals is 1.08MHz. Although this working bandwidth is higher than NB-IoT, it is much lower than ordinary LTE terminals. , can reduce device prices and chip computing power requirements, thereby reducing the overall price; lower peak rate, compared to LTE, lower peak rate reduces chip computing power and Buffer requirements, thus reducing chip prices; single terminal receiving antenna , reducing the cost of radio frequency components; the half-duplex solution can save the duplexer of the terminal radio frequency, thereby reducing the cost of the terminal.
3. LoRa
LoRa is one of the LPWAN communication technologies. It is an ultra-long-distance wireless transmission solution based on spread spectrum technology adopted and promoted by the American Semtech Company. This solution changes the previous trade-off between transmission distance and power consumption, providing users with a simple system that can achieve long distance, long battery life, and large capacity, thereby expanding the sensor network.
Currently, LoRa mainly operates in free frequency bands around the world, including 433, 868, 915 MHz, etc. LoRa technology has the characteristics of long distance, low power consumption (long battery life), multi-node, and low cost. The LoRa network is mainly composed of four parts: terminal (can have built-in LoRa-module ), gateway (or base station), server and cloud. Application data can be transferred in both directions.
Technical advantages
On-demand deployment: LoRa can plan and deploy the network according to application needs, and place base stations/gateways according to the on-site environment, making it easier to achieve seamless coverage. Improving coverage quality can also reduce power consumption and increase system capacity, both for individuals and enterprises. Or organizations can deploy it and security needs can be met, and the data can be kept private.
Lightweight: Compared with other LPWAN technology protocols, LoRa has lower system complexity, simple hardware implementation, and lower resource requirements. The lightweight LoRaWAN protocol has simple software implementation and simple deployment and implementation.
Low cost: LoRaWAN modules are in mass production, and the price is already below USD5, and is gradually approaching the price of 2G modules. Outdoor base stations are as low as around USD500, and indoor ones are USD100. From the perspective of foreign operators, LoRa monthly rent can reach eMTC monthly rent. 1/5~1/10 or even lower.
Comparison between NB-IoT and LoRa
Effectively deal with low ARPU: The APRU of a single connection is very low, and high investment will face the problem of low yield. High quality, lightweight, and low cost are the effective ways to deal with it.
Open ecology, mature industrial chain: nodes, gateways and cloud servers are fully open, equipment of various sizes is available, the network can be operated by itself, and different business and operating models are available.
The return on investment is high and economically feasible: If only the investment in base stations is considered, LoRa’s return rate is, based on an average base station cost of RMB5,000, it takes 6.25 months (half a year) to recover the investment in the base station. The rate of return of NB-IoT is, taking into account base station upgrades and new construction, assuming an average of 150,000 yuan/station, it will take 187.5 months (15.6 years) to recover the base station investment.
Toepassingsscenario's
LoRa technology is very suitable for IoT applications that require low power consumption, long distance, a large number of connections, and location tracking, such as smart meter reading, smart parking, vehicle tracking, pet tracking, smart agriculture, smart industry, smart cities, smart communities, etc. and other applications and fields.
Challenges faced
City-level network coverage: LoRa has no operator expenses and is inherently weak in network deployment.
Spectrum resources: LoRa uses free frequency bands, which may cause interference problems. Although LoRa itself has strong anti-interference capabilities and the LoRaWAN protocol itself has measures to avoid interference, physical interference is difficult to completely avoid.
Countermeasures: Eliminate fragmentation, build a unified wide area network, network co-construction, and resource sharing. At the same time, it needs to be lighter weight and lower cost. The cost of the LoRaWAN module needs to be in line with the cost of the 2G module, or even close to the WiFi module.
In the process of developing and commercializing Internet of Things technology, our country has always lacked the mastery of some key technologies, so the product quality cannot be improved and the price cannot be lowered. The lack of independent property rights for key technologies such as RFID is one of the key factors limiting the development of China’s Internet of Things. Compared with the United States, there is still a large gap in the completeness of the domestic IoT industry chain. Although the three major domestic operators and system equipment vendors such as ZTE and Huawei are already world-class, other links are relatively lacking. The industrialization of the Internet of Things will inevitably require the full cooperation of upstream and downstream manufacturers such as chip manufacturers, sensing equipment manufacturers, system solution manufacturers, mobile operators, etc. Therefore, to develop the Internet of Things in our country, there is still a lot of work to be done in terms of institutions, such as Strengthen cooperation with industry authorities such as radio and television, telecommunications, and transportation to jointly promote the establishment of informatization and intelligent transportation systems.
The application fields of the Internet of Things are very wide, and many industry applications have great overlap. However, these industries belong to different government functional departments. To develop information applications based on sensing technology, such as the Internet of Things, in the industrialization process It is necessary to strengthen the coordination and interaction of the competent departments of various industries, cooperate with an open mind, break down the barriers between industries, regions, and departments, promote resource sharing, and strengthen system optimization and reform, so as to effectively ensure the smooth development of the Internet of Things industry.
For IoT communication technologies, each technology has its own characteristics and advantages to meet different demands and markets. Multiple LPWAN technologies will flourish and coexist.