Advanced Relaying In Future Wireless Cooperative Networks

Abstract

The conventional wireless cooperative networks (WCNs) are mainly designed for battery-powered and human-operated terminals. The next generation of WCNs is designed for a large number of autonomous machines. Replacing the batteries of the countless machines is highly undesirable. Very recently, a radio-frequency (RF) energy harvesting technique is proposed that the relay can now harvest energy from the surrounding RF signals, and a new kind of network, termed wireless-powered cooperative network (WPCN), emerges. However, the high attenuation of RF energy transfer confines the performance of WPCNs. In the first half of this thesis, we adopt the energy accumulation (EA) to combat the high attenuation. The relay with EA can accumulate the harvested energy and forward the received signal to destination in an appropriate block with an appropriate transmit power. Apart from wireless energy harvesting and transfer, another important trend for future WCNs is short-packet communication. This is because the machine-to-machine communication in the next generation of WCNs is intrinsically formed by burst packets with limited sizes. The conventional WCNs use extremely long packets to transmit information in order to achieve an error-free transmission. However, error-free transmission becomes impossible when replacing long packets with short packets. The conventional WCNs thus need to be revisited and the latter part of this thesis focuses on the performance analysis and optimization for WCNs under short-packet communication scenarios.