This volume constitutes the proceedings of the 4th International Conference on Frontiers in Cyber Security, FCS 2021, held in Haikou, China, in December 2021. The 20 full papers along with the 2 short papers presented were carefully reviewed and selected from 58 submissions. The papers are organized in topical sections on: intelligent security; system security; network security; multimedia security; privacy, risk and trust; data and application security.

Offers practitioners, researchers, and academicians with fundamental principles of cooperative communication. This book provides readers diverse findings and exposes underlying issues in the analysis, design, and optimization of wireless systems.

Cooperative devices and mechanisms are increasingly important to enhance the performance of wireless communications and networks, with their ability to decrease power consumption and packet loss rate and increase system capacity, computation, and network resilience. Considering the wide range of applications, strategies, and benefits associated wit

This proceeding covers topics such as universal sourcing code, estimation, cyclic codes, multi-user channels, synchronization, CDMA sequences, pattern recognition and estimation, and signal processing techniques. Applications to communications channels and recovery from faults are described.

This book brings together a group of visionaries and technical experts from academia to industry to discuss the applications and technologies that will comprise the next set of cellular advancements (5G). In particular, the authors explore usages for future 5G communications, key metrics for these usages with their target requirements, and network architectures and enabling technologies to meet 5G requirements. The objective is to provide a comprehensive guide on the emerging trends in mobile applications, and the challenges of supporting such applications with 4G technologies.