Modeling dynamics of complex wireless networks

In this paper, we present a unified model for the analysis of a number of wireless network characteristics leading to the existence of uncertain links. The probabilistic characterization of the link uncertainty enables the random graph representation of the network topology and use of existing tools of complex networks in the system analysis. In the analysis, the multi-hop concept is adopted to model future networks with dense user population and enable mobile to mobile (m2m) connections. The potential users acting as relays may belong to different operators and as such may or may not want to cooperate. Consequently, the existence of those links will be uncertain. Some subareas of the cell will be covered by other technologies such as femto cell or WLAN enabling the possibility for the cellular system to offload the traffic. The existence of those links depends on the relaying distance and coverage of the WLAN, as well as the cooperation agreement between the operators. Our model includes also the possibility to consider green networks where the link uncertainty results from the effort to prevent the radiations from the terminal towards the user. In addition, security requirements may not accept every available relay. For this reason, the existence of the link, even when physically present, will be also uncertain. In such a complex network, cognitive links are also available with limited certainty due to unpredictable activity of the primary user. The uncertain and time varying existence of the links and nodes results into a Dynamic Network Architecture (DNA). AU these characteristics of the network are incorporated in a unified model enabling a tractable analysis of the overall system performance.