Modeling and Analysis of Heterogeneous and Cognitive Cellular Networks

Yamuna Dhungana
2016
The unprecedented escalation in the data traffic demand due to rapid proliferation of smart phones and tablets cannot be fulfilled with the advancement in radio link technologies only as the radio link efficiency is fast approaching its limit. This problem motivates new paradigms of network deployment and spectrum utilizationheterogeneous network (HetNet) and cognitive radio. This thesis addresses the coexistence and interference management challenges in HetNets and cognitive radio networks
more » ... e exploring the capacity and reliability improvement opportunities. Due to the increasing irregularity in the spatial deployment of the network nodes in HetNets and cognitive radio networks, the stochastic geometry based modeling and analysis is adopted. The idea is to abstract the locations of the network nodes with a suitable point process and then analyze the average behavior of the network using tools from stochastic geometry. With this approach, the cell range expansion (CRE) method of load balancing supported by interference coordination via resource partitioning for the capacity improvement in HetNets is analyzed. In order to accurately model the network interference, the cell-load is also incorporated in this analysis. To understand the coexistence between the multi-antenna techniques and HetNet, and how they complement each other for the network throughput improvement, a tractable framework for modeling and analyzing a multi-antenna HetNet is developed, along with comprehensive performance evaluation of beamforming, multi-user spatial multiplexing and interference nulling techniques in the presence of perfect as well as imperfect channel state information (CSI). Motivated by the lack of error probability analysis of the cellular networks in the presence of inter-cell interference, a mathematical framework for computing the ii average error probability of a typical cellular user is introduced. Uniform approximation (UA) method for the average error probability analysis in Poisson field of interferers is also developed to simplify the analytical complexity of the existing results. To alleviate the spectrum scarcity problem in future cellular networks, an underlay method of cognitive secondary access to television (TV) spectrum is analyzed, and a relay transmission technique to improve the performance of secondary users is proposed. iii
doi:10.7939/r3f18sp2q fatcat:dtv6snvdlbdb5kp55i5cranseu