Development Of Protocol And Algorithm Research In LTE-Based Cognitive Wireless Networks

Recently, researchers have paid close attention to cognitive radio. However, it is so far from industrialization. To quicken the step of cognitive radio’s industrialization, we are really in need of a demonstration platform to verify those key technologies. What we have discussed in this paper is how to build such a platform.Considering the requirement of backward compatibility, we decide to build a cognitive wireless network demonstration platform based on Time Division Long Time Evolution (TD-LTE), to support the cognitive function by making a little modification to existing LTE protocol. This work was sponsored by National Key Technology R&D Program of P.R.China and National Basic Research Program of P.R.China. I am responsible for the design of simplified physical (PHY) layer protocol, link-level simulation on Matlab, development on Digital Signal Processor (DSP) and some research based on our proposed cognitive wireless network architecture.The paper is organized as follows:Firstly, we introduce the background of cognitive wireless network, key technologies and some existing cognitive-related prototype around the world. In addition, the architecture of LTE and air interface is overviewed. Based on that, we further clarify the necessity of designing the protocol of cognitive wireless network based on LTE and designing the algorithm based on cognitive wireless networks.Secondly, after deep analysis of each layer of LTE protocol, we have proposed the simplified protocol. Combined the new added cognitive message on Radio Resource Control (RRC) layer and the new added logic channel Cognitive Control Channel (COGCCH) on Medium Access Control (MAC) layer, the simplification of each physical channel and the modified RE mapping scheme is described detailedly.Thirdly, the paper goes on to introduce the PHY development on software-defined radio according to the designed PHY protocol. After giving some introduction to C6416 DSP, we describe the whole process of PHY development, including the design of hardware architecture, the planning of program architecture and some coding work on DSP.Then, we continue to do some research on scheduling algorithm in cognitive wireless networks, in order to provide some theoretical support for the platform when selecting effective scheduling algorithm. This part is based on two accepted paper.Finally, a conclusion is summarized at the end of this thesis, and the future directions are pointed out.