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Those advances mentioned in the above have changed internet to mobile internet. Internet means computer‐to‐computer communication. Mobile internet means mobile computer (cell phone)‐to‐mobile computer communication. At this moment, the rapid advances in 5G and AI require Moore’s law to keep going ahead for at the least another 10–20 years, but Moore’s law is ending.

In human civilization, the technique of communication has advanced step‐by‐step slowly from language, written words, printing, telephone and telegraph, television, internet, and now to mobile internet. Today, the advanced communication technology behind mobile internet is defined as 5G, with a standard of certain required performance. Figure 1.3 shows the drawing of a flower, which has six petals. There are two sets of petals: the inner brighter ones and the outer darker ones. The latter represents 5G technology and the former represents 4G technology. Each petal defines a specific technical requirement, as shown in Table 1.1. For example, on point‐to‐point latency of signals, it was 10 ms in 4G and about 1 ms in 5G. If we can advance the required performance beyond the petals of 5G, it will be 6G.

Figure 1.3 The petals of flower, which shows the required functions in 4G and 5G communication technology.

Table 1.1 5G technical requirements.

Primary requirements:End‐to‐end latency (mille sec)Peak data rate (mobility, km/h)Traffic volume density (tens of Tbps/km2)Density of base stations (104/km2)Internet of everythingEnergy efficiency

Secondary requirements:Security and reliabilityLow cost

In 2014, it was already predicted that around 2020, the 5G technology will be widely available. However, the company, Huawei in China, announced that its 5G technology is ready in 2019, ahead of everyone. It became a critical issue in the trade war between China and United States. The latter has put Huawei on its entity list or ban list. The hardware in 5G consists of satellites, servers, optical fiber lines, base stations, cell phones, and terminal sensors, and the software consists of various mobile internets, such as Android of Google. Huawei is especially good at making base stations.

Data and signals can be transmitted via satellites in sky, but satellites can be shot down easily in the beginning of a war. It can be transmitted via optical fibers underground and across oceans. The making of optical fiber requires the doping of rare‐earth elements, so the strategic importance of rare‐earth elements can be appreciated. Also it can be transmitted via base stations on land surface, so the construction of a large number of base stations is of national security concern. It is worth mentioning that Taiwan has successfully used its network of base stations to detect and control the motion and contact of people with Covid virus.

In the late nineties, dot‐com was developed but soon burst because cell phones were not available. After cell phone becomes popular, Apple, Microsoft, Amazon, etc. are now the biggest companies in the world, no more GE, IBM, and Exxon, because of the wide applications of mobile technology.

About the global standard of requirements in 5G technology, see Table 1.1, the first is point‐to‐point latency of signals, which is only a few milli second. Latency means the total time spent to send out a signal and to receive it back. In a chain of moving cars, if the first car stops suddenly, the second car must stop within the time of latency, otherwise an accident would occur. If we consider a human‐less vehicle, the LiDAR (not radar) on top of the car should be able to detect a sudden appearance of a pedestrian or a car, so that it can stop to avoid an accident.

Moreover, LiDAR and radar are line‐of‐sight techniques. Yet, we need to have a network of vehicle‐to‐everything in order to have non‐line‐of‐sight awareness to know what is behind a stationary or a moving object. Also it should have an ultrafast rate of transport of data in order to show clearly the change of images of the surrounding of a car moving at high speed. Besides, it can download or upload instantly news or weather reports. To download a movie will now take only three seconds in 5G technology. For the success of 5G, it must have a very large number of base stations, so that information can be received and transmitted continuously from place to place. It is no need to explain other standard requirements in Table 1.1, they should be clear. For example, any device being used under the hood of a car should have a high reliability because of heat. Then, low cost is important for the use of internet of everything in our home and office.

No doubt, 5G technology will enhance AI applications. At the end of this book, in Chapter 14, we shall discuss the need of using AI to accelerate the study of reliability, so that we may change it from a time‐dependent event to a time‐independent event. Another area for the use of AI will be the biomedical and health applications. For example, Chinese medicine has been based on big data for many years, and the technique of acupuncture could be improved with modern microelectronic devices. The link between microelectronics and biomedical applications will be the most important advanced technology in the future.