# 5G Mobile Services and Scenarios: Challenges and Solutions
## 1 Introduction  
We are now heading towards the fourth industrial revolution, which is based on digital revolution and marked by emerging technology breakthroughs in artificial intelligence, quantum computing, robotics, nanotechnology, biotechnology, etc. [1]. This new wave of technological revolution is changing the way we work, live, and communicate with each other. We can see emergence of unprecedented applications and services such as artificial intelligence, smart home, autonomous vehicles, drone-based delivery systems, smart cities, smart factories, etc. The co-existence of machine and human centric services will diversify the future wireless environments with the cost of challenges. In the near future, mobile communication will penetrate every part of society and create a multidimensional, user-centric information ecosystem. In addition, a fully mobile and connected society is expected, which will be characterized by an incredible amount of growth in connectivity, traffic volume, and a much broader range of usage scenarios [2]. The traditional business model of mobile communications has been disrupted by Mobile Broadband (MBB) service, enabling unprecedented user experiences and making a deep impact on every aspect of people's life and work. Accompanying the large-scale commercialization of 4G, the fifth generation of mobile communications (5G) is expected to be commercialized around 2020 and has become a central point for global research and development. Regardless of advanced 4G network, it is difficult to provide mobileservices that need high speed, high reliability, rapid response, and energy efficiency. Existing 4G networks cannot deliver instant cloud services, enhanced Vehicle-to-Everything (eV2X), Internet of Things (IoT) [3], tactile internet [4; 5], and robots and drone communication, considering the quality of experience (QoE) to mobile users. These characteristics have become vital necessities for future services in the 5G era. The recent research on 5G services and their technical requirements have been performed by the International Telecommunication Union-Radio communication Sector (ITU-R), the Next Generation Mobile Networks (NGMN) Alliance and the 3 rd Generation Partnership Project (3 GPP). In the ITU-R Working Party (WP) 5D, 5G is defined by the name of International Mobile Telecommunications-2020 (IMT-2020) [6].  
Based on end users' experience, several 5G services are categorized into five groups. The new 5G services are as follows: immersive 5G services, intelligent 5G services, omnipresent 5G services, autonomous 5G services, and public 5G services. As mobile multimedia content streaming and social networks have become more widespread, the demand for mobile traffic has continuously increased. Table 1 summarizes the five service categories of 5G. In addition, new types of multimedia services such as augmented reality, virtual reality, etc., which all require huge traffic volumes, have emerged [7].  
The vision of 5G is to provide super ultra-low latency user experience, fiber-like access data rate, connect more than 100 billion devices and deliver a consistent experience across diverse scenarios with enhanced energy and cost efficiency.