A survey of next generation mobile communications research in China

Abstract

With the rapid development of wireless communication networks, the fourth generation (4G) has emerged to move beyond the limitations of the third generation (3G), with increased bandwidth, enhanced quality of services, and reduced costs of resources. In this paper, we discuss the key technologies of 4G and focus on surveying the ongoing research in 4G communications in China. The 4G technologies under investigation include multicarrier transmission, multiple antenna techniques, carrier aggregation, relays, cognitive radio, distributed antenna systems, network convergence, and network self-optimization. These technologies are the building blocks of 4G and contribute largely to the requirements of International Mobile Telecommunications Advanced (IMT-Advanced). For each technology, its benefits, research topics, and some existing approaches are examined. Finally, we briefly discuss the challenges and future research issues in 4G systems. multicarrier transmission, multiple antenna techniques, carrier aggregation, relay, cognitive radio, distributed antenna system, network convergence, network self-optimization Citation:The limitations of the third generation (3G) and the rapid growth in user demands has called for more advanced and efficient technologies for new generation systems. The upcoming fourth generation (4G) mobile communication systems are expected to solve the still-remaining problems of 3G systems and to provide a wide variety of adaptable services for mobile and nomadic users by using integrated heterogeneous network infrastructure. Based on a comprehensive and secure internet protocol (IP) solution, various services, such as voice, video, broadcasting media, and Internet, will be provided to users with high data rates anytime and anywhere. This is also known as the always best connected concept stating that a user can have the best service connection regardless of time and location.According to the steadily increasing demands and technology developments, wireless communication evolution can be grouped into different generations of networks. Each new generation has brought advances that revolutionized the field of mobile communication. The first generation (1G), initiating commercial mobile voice services with analog techniques, built the basic structure of mobile communications and solved many fundamental problems such as the multiplexing frequency band, roaming across domains, non-interrupted communication in mobile circumstances, and so on. The second generation (2G) of wireless technology, which marked the switching of mobile communication technology from analog to digital, offered higher capacity and lower costs for network operators as well as messages and low-rate data services for users, by using a circuit switch infrastructure. Working under 2G's framework, 2.5G brought the internet into mobile personal communications based on a packet switched radio connection technique. 3G systems, a mixture of packet and circuit-switched networks, are committed to achieving greater network capacity

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