TUT-05: Aerial Access Networks for 6G: From UAV, HAP, to Satellite Communication Networks

The current development of 5G networks represents a breakthrough in the design of communication networks, for its ability to provide a single platform enabling a variety of different services, such as enhanced mobile broadband communications, automated driving, Internet-of-Things, with its huge number of connected devices. Nevertheless, looking at the significant enhancements enabled by 5G, it is already possible to envision the need to move sixth generation (6G) with a new architecture incorporating new services and technologies. Providing “connectivity from the sky” is one new innovative trend in wireless communications for beyond 5G or coming 6G communication systems. Satellites, high and low altitude platforms, drones, aircrafts, and airships are being considered as candidates for deploying wireless communications complementing the terrestrial communication infrastructure. Utilizing modern information network technologies and interconnecting space, air, and ground network segments, the aerial access network (AAN) has attracted many attentions from both academia and industry, which has been recognized as a potential solution for the 6G systems. AANs are subject to heterogeneous networks that are engineered to utilize satellites, high-altitude platforms (HAPs), and low-altitude platforms (LAPs) to build network access platforms. Compared to terrestrial wireless networks, AANs are characterized by frequently changed network topologies and more vulnerable communication connections. Furthermore, AANs have the demand for the seamless integration of heterogeneous networks such that the network quality-of-service (QoS) can be improved. Thus, designing mechanisms and protocols for AANs poses many challenges. To solve these challenges, extensive research has been conducted. Notice that AANs are not intended to replace the above existing technologies, but instead to work with them in a complementary and integrated fashion. However, design, analysis, and optimization of AANs require multidisciplinary knowledge, namely, knowledge of wireless communications and networking, signal processing, artificial intelligence (e.g., for learning), decision theory, optimization, and economic theory. Therefore, a tutorial containing the basic concepts/theories for addressing the research advances that enable aerial communications in cellular networks as well as the state-of-the-art of research and development and the related information will be very useful for researchers and engineers. This is the primary motivation of this tutorial.