Fiber-connected massively distributed antenna systems : energy efficiency and interference management

• Main Author: Li, Haoming
• Language: English
• Published: University of British Columbia 2013
• Online Access: http://hdl.handle.net/2429/45199

The density of wireless access nodes keeps increasing to provide ubiquitous wireless access and meet the ever-increasing traffic demand. However, the shrinking distance among neighboring access nodes causes excessive interference and the increasing number of access nodes incurs a higher power consumption. A careful management of interference ensures a high system capacity. An improved energy efficiency in wireless access network prevents the fast growth of wireless communication systems from aggravating the global energy crisis. In this thesis, we propose a novel architecture, Fiber-connected Massively Distributed Antennas (FMDA), to address the challenges of managing interference and improving energy efficiency in wireless access networks. A FMDA system is composed of a centralized processing system connected to a large number of antennas via optical cables. The centralized processing system processes all the radio signals and allocates all the radio resources to better manage interference; each antenna contains much simpler circuits than conventional access nodes and therefore allows a massive deployment and reduces the antenna power consumption. We first propose a novel multi-cell wireless local area network (WLAN) system based on our proposed FMDA architecture, where the centralized processing system can see the entire spectrum usage across the coverage area and control the radio signals to be sent to each antenna, thus allowing a better management of inter-cell interference. We then propose an antenna scheduling scheme in a novel cellular system composed of fiber-connected femto access nodes to manage the excessive inter-femtocell interference and reduce the energies consumed by non-sleeping access nodes, thus simultaneously improving the spectral and energy efficiency. When the number of cooperating antennas increases, the power consumption of signal processing spikes, thus drastically degrading the overall energy efficiency due to much smaller radio transmission power levels. Focusing on two typical indoor environments, office buildings and large public venues, we propose two low-complexity downlink transmission schemes to address these energy efficiency challenges. === Applied Science, Faculty of === Electrical and Computer Engineering, Department of === Graduate