Research On Spectrum Monitoring And Data Fusion Technology Of Cognitive Radio Network

With the progress of society, the demand of people for wireless data communication services is also growing, the Internet has become a necessity in people’s normal work and life now. The ultimate goal of wireless communication is that anyone can easily get access to the Internet at any time or place through wireless transmission. Since the spectrum resources are limited, and the demand for spectrum resources is growing, leading to this contradiction more prominent. For decades, people spend too much time in systems, protocols, and network structures in a variety of wireless communication systems, and use a lot of wireless technologies to build different wireless communication systems. Now people still face a huge challenge in modern wireless communication technology, which is how to obtain sufficient spectrum resources or change the status of low utilization of the spectrum resources.As an intelligent spectrum sharing technology, cognitive radio enables secondary use of spectrum resources, achieve how to improve the efficiency of spectrum usage under condition of limited spectrum resources effectively.Based on the study of cognitive radio system and its key technology, we focus on the spectrum monitor technology, especially the energy detection as the core technology. We launch a series of studies on how to improve the reliability of secondary user to monitor the primary user channel. The main work includes:(1) We establish a cognitive radio network model in fading environment, in the presence of Gaussian noise and Rayleigh fading environment, we simulate the system performance and comparative analysis of a single-user sensing independently and multi-user sensing cooperatively, obtain a result that through cooperation between cognitive users can reduce uncertainty of multipath fading caused by a single-user detection.(2) In the cognitive radio network system model in fading environment established in this paper, we analysis of the cognitive radio network in which each secondary user at different locations (ie, the distance between secondary users and cognitive base stations) in different environment affects the performance of the system.(3) We introduce and analysis the data integration in cognitive radio network in detail, describe the result of or criterion, and criterion, and K/N criterion in traditional centralized collaborative detections. Based on it we study a new way of data integration-integrate data after removing the singular point, and through simulation comparison and analysis, we prove that the new data integration method superior.