Controlling Intercell Interference in CDMA-based Fixed Wireless Networks Through Multirate Techniques

作     者：Arapoglou, Pantelis-Daniel M. Papaioannou, Petros I. Panagopoulos, Athanasios D. Cottis, Panayotis G. 

作者机构：Natl Tech Univ Athens Wireless & Satellite Commun Grp Div Informat Transmiss Syst & Mat Technol Sch Elect & Comp Engn Athens 15780 Greece 

出 版 物：《WIRELESS PERSONAL COMMUNICATIONS》 (无线个人通信)

年 卷 期：2010年第54卷第4期

页      面：729-744页

核心收录：

学科分类：0810[工学-信息与通信工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 

基　　金：This work is supported by the Programme of the 8th Session of the joint Greek-Italian Scientific and Technological Co-Operation 2006–2008 

主　　题：CDMA based LMDS IEEE 802.16 Multicode CDMA Orthogonal variable spreading factor CDMA Cochannel interference 

摘      要：A number of research works have suggested a possible capacity advantage when employing direct sequence-code division multiple access (DS-CDMA) instead of the more common time division multiple access option for fixed broadband wireless access networks operating at millimeter-waves. The choice of this multiple access scheme, which, up to now, has not been foreseen by recent WiMax (worldwide interoperability for microwave access) standards, exhibits an improved performance in terms of cochannel interference in the upstream, even though it experiences higher interference in the downstream. The present paper focuses on enhancing the bottleneck downstream performance of fixed wireless networks by proposing a methodology for controlling the signal-to-interference ratio throughout the cell, so that all subscribers meet the given interference quality-of-service specifications. This is accomplished by exploiting the properties of a combination of multirate CDMA techniques. The paper describes a simple policy for code assignment, which is proved to be optimal, incorporating the effect of rain fading over multiple paths. The performance of the algorithm is tested against single code DS-CDMA both under long term channel statistics (static code assignment) and under dynamic channel effects (dynamic code assignment). The first test verifies the compliance of all sector subscribers with more demanding SIR specifications, while the second yields a significant improvement in terms of resource utilization.