Study Of Coordinated Multi-Point Transmission And Reception With Backhaul Delay And The Improvement Of System Performance

Co-ordinated Multi-Point transmission/reception(CoMP) is introduced by3GPP to improve the cell edge throughput in LTE-Advanced. Coordinated multi-point transmission refers to multiple transmission geographically separated points collaboratively transmit signals to more than one users or receive the data which is transmitted by more than one users. CoMP improves the spectrum efficiency and the system performance especially the cell edge performance by breaking the limit of the former one user to one base station transmission. However, CoMP is based on information exchange between the base stations, which makes the backhaul delay greatly increased. Backhaul delay causes real-time channel state information deteriorate and reduces or even cancels the system performance gain brought by CoMP. So it is necessary to study the backhaul delay. Nowadays the study on system delay is not fully studied and X2backhaul delay can be divided into different types which has not been studied. Therefore, this thesis concentrated on non-zero delay systems and conducted a more in-depth study.In the analysis of non-zero delay system, this paper has divided system delay into three parts:feedback delay, cooperative scheduling delay and data synchronization delay. Then the analyzation of system delay from user plane and control plane is described separately. At the end of this paper, we build up the simulation platform and simulate the non-zero delay system performance under various cooperation scenarios, scheduling algorithms and different threshold for deciding CoMP users. Based on the results of analyzation and simulation, this paper gives some suggestions to improve the performance of non-zero delay CoMP system...