Call admission control considering various service classes in 3G wireless systems

Abstract

Nowadays, mobile communication networks have evolved into 3G systems which accommodate various data communications as well as voice communications. 3G mobile communication networks aim at effective provision of packet data service such as internet or multimedia service, and these services request mobile network capacity more and more. Unlike internet which is a packet switching network, a general mobile communication network is a circuit switching network, and it requires efficient Call Admission Control (CAC) in order to manage limited radio resource efficiently. Since the circuit switching networks were developed, much engineering work has been done on the topics of efficient CAC; nevertheless, previous works are probably not directly applicable to a 3G system, because it has many different features from before 3G systems. Therefore, we will study previous CAC methods, and then, on the basis of them we will propose novel CAC schemes suitable for 3G systems. In addition, we will consider CAC at both rural and urban cell environment in Wideband Code Division Multiple Access (WCDMA) system for more practical study. In Chapter 2, efficient CAC at the rural cell environment is considered. First of all, radio resource reservation methods which have been considered in previous CAC schemes are studied and classified into several representatives. Then we examine them in the order of development, and improve them into suitable methods for 3G systems. In addition, we propose novel CAC schemes for the purpose of better performance in 3G systems. Computer simulations are performed to evaluate the performance of proposed schemes compared with previous schemes. Secondly in Chapter 3, the urban cell environment is considered. Since urban cells generally have more customers than rural cells, call admission requests are also more frequent in urban cells. For these reasons, it is easily expected that the larger data transmission capacity of a base station will be required i...