Reception of Multiple Users in Reconfigurable Wireless Networks

Abstract

The next generation of wireless networks (WNs) will confront important challenges pre- sented by the high density and convergence of wireless elements (WEs), their influence on our lifestyle, and the proliferation of new paradigms of wireless communication systems. Co- existence, mobility, and multiple access are some issues widely studied in order to ensure their operation. In this work. it is introduced a framework of WNs considering association schemes, networking, and coexistence aspects which are useful concepts to describe their fea- tures and the relationship among elements. Code division multiple access (CDMA) systems are considered as attractive models to future wireless communication systems (WCS) in order to affront the new and changing challenges. Traditional direct sequences - code division multiple access (DS-CDMA) and double codification division multiple access (C2DMA) models provide engaging features given that offer continuous access to the wireless channel to every user, i.e. they permit coexistence of multiple users at the same time. These models are interference limited systems what make them vulnerable to usual issues in dynamic networks such as the Near-Far problem, Hidden and exposed terminals interference, etc. However, C2DMA model has been shown addi- tional properties that makes it attractive to reconfigurable wireless networks (RWNs) due to its robustness to interference. It considers a double correlation technique which provides si- multaneous reception and motivates the study of sequences used as codes in order to increase their use and visualise some applications. This work considers current and new sets of codes through an exhaustive search of useful sequences for both models. First, desired properties are identified for each model, next known sequence sets are tested with these properties. After that, an exhaustive search algorithm is used in order to select and group sequences to form all the possible code sets with desired properties. Finally, these models are tested in challenging scenarios in order to examine their performance and persuade about their potential in future WNs.