On the Spectral Efficiency and Energy Efficiency of the Cloud Radio Access Network Architecture
Abstract
Providing support for high consumer data traffic and maintaining high system efficiency
are key requirements of the fifth generation (5G) wireless network design. The high costs associated with the widespread installation of the network base stations (BSs) and spectrum acquisition makes them impractical for accommodating the high traffic load. What is more, the continuous operation of the BSs also has a significant consequence in causing elevated levels of carbon dioxide (CO2) emissions. To meet the key requirements of high spectral efficiency (SE), maintain low levels of cost, and high energy efficiency (EE), cloud-radio access network (cloud-RAN) has been proposed as a promising architectural solution. Moreover, new waveforms (e.g., fillter bank multicarrier (FBMC)) have been suggested as alternatives to the traditional orthogonal frequency division multiplexing (OFDM) to satisfy the astounding growth in the traffic load. This thesis aims to enhance capacity and reduce the network power
consumption. First, the effect of cooperative transmission in combination with the cloud-RAN architecture on network-level achievable data rate along with EE and SE is studied. Mathematical tools from stochastic geometry are utilized, to analytically characterize SE and EE. Moreover, the ability to increase the power savings is investigated by incorporating a tunable downlink distance-based fractional power control (D-FPC) mechanism into the cloud-RAN architecture. Using tools from stochastic geometry, the network-level coverage probability and EE are examined. Second, the throughput reliability/SE/EE of a cloud-RAN incorporating the D-FPC mechanism along with cooperative joint transmissions is analyzed by adopting a stochastic geometry-based approach. Lastly, taking into account feasibility of two-fold data rate improvement within FBMC waveform, this thesis studies and experimentally examines FBMC waveform to evaluate this new waveform and compares it with OFDM waveform. Moreover, the linearity requirements of power amplifier (PA)
using memoryless and memory polynomial digital predistortion (DPD) techniques are also examined through a very nonlinear PA (Doherty) and a moderately linear PA (Class AB) to explore the behavior of OFDM and FBMC signals. Overall, this thesis provides critical insights to the cloud-RAN system designer for selecting appropriate architectural approach and waveform to achieve desired performance regarding energy, spectral, and PA efficiency.
Description
Keywords
Engineering--Electronics and Electrical
Citation
Ghods, F. (2017). On the Spectral Efficiency and Energy Efficiency of the Cloud Radio Access Network Architecture (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/27196