In 2002, digital communications redefined telephones and mobile communications began to take off. In 2010, mobile technology redefines calculations. Now, we are redefining everything, that is, the value of expanding the boundaries of the Internet, which is the Internet of Things. The Internet of Things has a very wide range of applications, from smart cities such as lighting, parking and transportation, can be connected and effectively managed; to mobile health, including patient diagnosis, tracking of patient conditions, various environmental monitoring; water meters at home, Remote tracking of electricity meters, gas, etc.; safety and intelligence of buildings; control of industrial automation; and vertical markets and market segments such as retail commerce and asset tracking. There are currently three kinds of wireless connection technologies for the Internet of Things in the 3GPP specifications. One is NB-IoT (narrow-band Internet of Things), the second is ECGSM, and the third is eMTC. ECGSM is based on GSM (2G) technology. For the time being, NB-IoT has been introduced in detail. Today's protagonist will be eMTC.
Definition of eMTC
LTE-M, LTE-Machine-to-Machine, is an LTE-based evolving IoT technology. It is called Low-Cost MTC in R12, and is called LTE enhanced MTC in R13, that is, eMTC, based on existing technologies. The LTE carrier satisfies IoT device requirements. The eMTC is deployed on a cellular network and supports peak rates of up to 1 Mbps for uplink and downlink. It is a rate in the Internet of Things. Its user equipment can directly access the existing LTE network by supporting radio frequency and baseband bandwidth of 1.4 MHz. In the process of continuous evolution of LTE, the latest eMTC and NBIoT have further optimized the cost of the system, enhanced the endurance capability, and expanded the coverage. The eMTC's most critical capability is to support mobility and can be positioned at a cost of only 25% of the Cat1 chip, which is four times higher than the GPRS rate.
eMTC features
Narrowband LTE is one of the most important features. First, the complexity of the system has been greatly reduced, and the complexity and cost have been greatly optimized. Second, power consumption is extremely reduced, and battery life is greatly enhanced. Third, the network's coverage capacity has been greatly enhanced. Fourth, the density of network coverage has increased.
The eMTC has the four basic capabilities of LPWA: First, wide coverage. With the same frequency band, the eMTC gains 15 dB more than the existing network, which greatly enhances the LTE network's deep coverage capability. Second, it has the ability to support massive connections. eMTC One sector can support nearly 100,000 connections; the third is lower power consumption, and the eMTC terminal module can have a standby time of up to 10 years; fourth, lower module cost, large-scale connection will bring module chip cost The rapid decline, eMTC chip target cost is about 1 to 2 dollars.
The evolution of Internet of Things R13 to R14
R14 opens 3G's 5G tour. Future 5G applications will cover three major scenarios: Enhanced Mobile Broadband (eMBB), Massive Machine Class Communications (mMTC) and Ultra-Reliable Low Latency (eMTC). Among them, the eMBB scenario refers to the improvement of the user experience and the like on the basis of the current mobile broadband service scenario, and is mainly to pursue the ultimate communication experience among people. mMTC and eMTC are the application scenarios of the Internet of Things, but their respective focuses are different: mMTC is mainly the interaction between people and things, and eMTC mainly reflects the communication needs between objects and things.
From the evolution of 3GPP Release 13 to Release 14, there is no particularly large networking terminal for throughput requirements. For example, in the broadcast function, only unicast can be supported in Release 13, and more in Release 14. Road broadcasting (multicast) function; In addition, if the positioning function is improved, its location can be tracked.
The advantages of eMTC technology
By 2018, shipments of non-mobile connected terminals are expected to exceed 5 billion. The IoT market, as a very broad vertical market, requires very strong connection support. The basic requirements are three points: the connection must be ubiquitous and always present. There must also be security assurances; at the same time, there must be a very well-developed and fully optimized ecosystem. So, the LTE-based IoT technology is the best candidate, and there are currently NB-IoT and eMTC.
There are many options for wide coverage of low-power IoT solutions. There are three ways to use a cellular network. The first one is based on 2G/3G/4G technology and uses the same terminal chip as the mobile phone. The capacity of mobile phone users is The second is a partial optimization scheme, including eMTC, Cat1, and Cat0, which can reduce cost and power consumption and enhance coverage. The third method is NB-IoT.
Looking at the LTE market today, as of April 2016, more than 500 operators in more than 160 countries worldwide have deployed LTE, and more than 400 manufacturers have released more than 5,000 products supporting LTE. With the rapid development of smart phones in the past few years, LTE has become the easiest and most easily guaranteed wireless communication mainstream technology. Compared to the Wi-Fi and Bluetooth technologies of the Internet of Things, LTE covers a wider range of connections. In addition, the eMTC can be directly upgraded and deployed based on the existing LTE network, and the existing LTE base station co-sites a total feeder. The eMTC and NB-IoT can largely reuse the network infrastructure of the current LTE FDD and TD-LTE, so with a small amount of equipment investment, the network can support future NB-IoT and eMTC and does not need to be rebuilt. A net. This is one of the reasons sought after by major operators.
Commercialization of eMTC
Applied in smart logistics, with anti-theft, anti-exchange, real-time temperature sensing and positionable advantages, real-time monitoring and positioning, information recording and uploading, you can query the track; in smart wearable devices, support for health monitoring , video services, data transmission and positioning; relying on the current cellular network interaction screen, provides application scenarios including smart charging piles, waiting treasures, elevator guards, smart bus stop signs, and public bicycle management.
Smart home in the Internet of Things
As a branch of the Internet of Things, smart homes are also in the ascendant market. At present, the two major problems of “smart combination†and “combination of connections†are the most important issues to be resolved. As smart home manufacturers, although the functions of intelligent hardware are increasingly rich, this only solves the problem of smart combination. We often talk about the interconnection and interoperability at the level of connection and combination. At present, we basically choose Wi-Fi, Bluetooth, ZigBee, Z-Wave and other close-range IoT communication technologies in the domestic smart home market, and we also see some choices for Lora. And Sigfox's application of two narrow-band Internet of Things technologies in smart homes, smart communities, and smart cities. However, because commercialization of the LTE-based Internet of Things technology NB-IoT and eMTC can be started next year, the connection options for smart homes in the future are still in an unknown stage. The market is almost all blank, but this blank is Large-scale strong demand lies.
After solving the problem of "smart combination" and "connection combination", it is "interactive combination". The interactive combination does not mean that the user controls a device through the mobile phone APP. It seems that this method is more advanced than the original, but it is still primitive and foolish. The interactive combination is the self-determination and self-processing between smart home devices and devices. It does not require human intervention at all, and it can also be called "upgraded mechanical fool." But "interactive combination" is still not the ultimate goal in the field of smart home. The non-mechanized and personalized processing of artificial intelligence will control the "interactive combination". We call it "personality combination", perceiving, thinking through learning, and analyzing the environment, The "personality" response that ultimately makes instincts is the end.
The development of IoT wireless technology will be challenged by many requirements, such as high density and high throughput, while also requiring low power and low latency; high speed and high stability at the same time; many complicated machine connections are required. Because the current wireless technology is still immature and has been questioned by many people, when the Internet of Things technology matures, it also marks the arrival of the “wireless connection†era of smart homes. At this time, the questioning voice will be eliminated, just as we are talking about the phone now. Think of a cell phone and not think of a fixed line.
Edit Comment
If you just translate the existing LTE technology to the Internet of Things terminal, it will not work, because in order to meet the wider IoT terminal connection, low power consumption and low data transmission rate are strong requirements. As we know Cat.4 to Cat.16, eMTC is Cat M1, and NB-IoT is Cat NB1. All belong to the same LTE development roadmap. eMTC cuts and optimizes LTE protocol. These technologies can also When operators deploy LTE coexist, NB-IoT and eMTC are complements of LTE IoT technologies. Regardless of who wins or loses, LPWA will promote the development of "connected portfolios" in third-party vertical industries such as smart homes, and expand more demand. eMTC can support voice VoLTE calls. NB-IoT can reduce the cost and power consumption to a minimum in low-throughput application scenarios. The eMTC and NB-IoT hardly have very clear boundaries. The two technologies will be integrated and supplemented. To enhance the user experience.
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