Why does Iot require 5 GB

Why does Iot require 5 GB

When the fifth generation of communication technology (5 Gb) arrived in 2020, engineers expected it to be able to process 1000 times the mobile data of today's cellular systems. Some people think that it will also become a backbone network of the Internet of Things (IoT), connecting fixed and mobile devices (such as fixed vending machines and automobiles) and become part of the new economic revolution. New Architectures, new communication technologies, and new hardware will make this change possible. Last month, at the Chinese Science Magazine, researchers at the University of Lancsater Ding Zhiguo reviewed current research and future 5g needs. In an interview via Skype, Ding talked to Spectrum about how 5G will change the future.

S (Spectrum): 4G is being deployed in many countries, but is it outdated?

D (Ding ):In fact, 4G is enough today, but in the next 5 or 10 years, new applications will emerge one after another, and 4G obviously cannot meet the requirements. 5G will increase the data rate, reduce end-to-end latency, and improve coverage. These features are especially important for many Iot-related applications. For example, in the recent emergence of self-driving vehicles and smart transportation, small latency is a must. Another example is that with the popularity of interactive mobile games, the demand for bandwidth is more urgent. Unfortunately, the current 4G does not support these features.

S:So 5G will play a basic role in Iot?

D:I think Iot will become an ideal 5g Application scenario. The current situation of Iot is that there are some independent systems. For example, we have RIFD and short-range communication technologies, such as ultra-wideband (UWB) and Bluetooth. When talking about a big map like a smart city, we need a seamless and unified framework, which is precisely a problem. 5G is just a good opportunity to provide a unified framework.

S:How does 5g deal with a large number of devices connected to IOT? Is the bandwidth sufficient?

D:The previous 1g-4G technology relies on the so-called orthogonal multiple access technology. Taking the time-division multiple access used in 2G as an example, we divide one second into many short intervals called time slots. Then we assign a specific time slot to each user, and a user cannot access the channel assigned to others. This orthogonal multiple access technology is difficult to support future Iot applications. We will have a large number of devices and we have to allocate dedicated time slots for each of them. However, due to the limited number of available time slots and bandwidth, we will not be able to achieve this in the end. This is why orthogonal multiple access technology is not applicable to 5g.

There are many studies on the non-orthogonal multi-access technology that can accommodate a large number of users on a limited bandwidth channel. Ideally, non-orthogonal multi-access technology will strike a better balance between system throughput and user fairness. Of course, there will be interference between users, and some users can only experience low data rates. However, it is very interesting that many devices only need to maintain a low speed in time in the Iot. For example, in wireless medical care, wearable devices (such as heartbeat detectors and biosensors) need to send patient data to hospital servers in a timely manner, but these devices use a low data rate. By using non-orthogonal multi-access, we can squeeze a large number of Iot users/devices with different service quality requirements into the same time slot or band. In this sense, the concept of non-orthogonal methods is very exciting and perfect for Iot.

Another way to explain the benefits of orthogonal multiple access is to regard non-orthogonal multiple access as a special case of Cognitive Radio technology. Currently, we allocate a single bandwidth or channel to a user. This channel cannot be reused because it is occupied by this user. Through cognitive radio communication, we can allow new users to access this channel. If there is a good connection between these users and the base station, we can achieve a high data rate. Of course, this will also cause some performance degradation for the initial users, but when these initial users have poor connection to the base station or they have achieved a fine power control mechanism between users, this decline is not very serious.

S:How do I deal with "spectrum shortage" in 5g preparation (the available frequency band is full )?

D:To solve the spectrum shortage problem, we need a combination of technologies. One way is to improve the efficiency of available bandwidth. In this sense, we can apply non-orthogonal multi-access, large-scale MIMO, cloud wireless access network, full duplex, and so on.

Another method is to use a shorter Millimeter Wavelength, 60 or 90 GHz, and more spectrum bandwidth can be used for telecommunications. There are some challenges. For example, the higher the frequency, the more severe the air attenuation, which eliminates the possibility of long-distance transmission. In addition, there is also a problem of occlusion, which requires a complete line of sight transmission between the transmitter and the receiver. This problem can be solved through multiple antennas. When a link is blocked, there are other links between the transmitter and the receiver. It is worth noting that in many Iot application scenarios, millimeter wave communication is promising, and there is a line of sight connection between sensors and the distance is not long.

S:What are you going to do next?

D:The 5G progress schedule has not been officially confirmed. It is widely predicted that formal discussions and standardization activities will be launched next year, and commercial deployment will begin in 2020. The industry and academia are working together to identify which standards and technologies should be used and which will not.