Recursive Beamforming Design for Wireless Information Transfer in Coordinated Multi-Point System with Partial CSI

• Main Authors: Yao-yuan Chang, 張耀元
• Other Authors: Wan-Jen Huang
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/99606713093789848417

碩士 === 國立中山大學 === 通訊工程研究所 === 102 === In recent years, wireless communication has been developed quickly, and the mobile network has proceeded to the fourth generation communication systems. The subscriber’s handheld devices are going to have higher quality services and faster transmission throughput. In the fourth generation partnership project, coordinated multi-point (CoMP) transmission technique has been proposed to enhance the signal quality of the Long-Term Evolution-Advanced (LTE-A) systems. Through coordination among multiple cells, e-NodeBs (eNBs) adjust corresponding transmit beamforming vectors in order to reduce co-channel interference as well as improve transmission throughput of users located at cell edge. Downlink coordinated multi-point transmission techniques can be classified into the joint processing (CoMP-JP) and coordinated beamforming (CoMP-CB). On the other hand, as the development of semiconductor, mobile devices become more powerful and are usually equipped with high quality panel, which consumes battery power faster. However, progress on the battery is not as faster as electronic devices. Thus, the technique of wireless energy transfer (WET) has been proposed to harvest energy and provides longer lifetime for the user’s devices. In the thesis, we consider a CoMP system where users need to receive information and harvest energy simultaneously. We focus on the design of beamforming vector to meet the requirement of energy harvesting and information detection. Taking implementation complexity into consideration, we propose a downlink CoMP-CB scheme where each user can operate under either energy-harvesting mode or energy-detection mode. By optimizing the beamforming vectors and selecting operation modes for users, the proposed scheme aims to maximize the harvested energy, subject to guaranteeing sum-rate constraints for those users in information-detection mode. Finally, we also consider the case of partial CSI, and design the beamforming scheme accordingly, in order to deal with the situation that perfect CSI is not available.