Grass-root based SpectrumMap database for self-organized cognitive radio and heterogeneous networks: Spectrum measurement, data visualization, and user participating model

With the higher demanding of radio frequency resources in wireless networks, spectrum management has been a politically as well as a technically sensitive issue. It is usually difficult to access the open data of real spectrum usage. In this sense, we believe grass-root based spectrum data collections are important. In this paper, we propose a grass-root based spectrum database architecture and show the insights for the aspects of the spectrum awareness regarded to dynamic spectrum access. The main contributions are: (1) A grass-root based spectrum database has been designed with the introduction of spectrum data visualization by the SpectrumMap. (2) We have taken large-scale spectrum measurement campaigns continued in several years in Tokyo and evaluated typical bandwidths utilizations. Specially, we show spectrum usages of WiFi in city center environment. (3) We have developed a Hadoop based web system for SpectrumMap to improve big data processing and provide spectrum data visualization in user-friendly access interface with flexible exploring functions about frequency usages. (4) To enable grass-root based data collections, we have proposed a participating model to encourage users to join the SpectrumMap, through integrating different kinds of users of cognitive radio network, WiFi, as well as heterogeneous networks, to collect radio environment data and share it with the SpectrumMap. The proposed grass-root based spectrum database in user participation model is expected to work in an open access model as a supplement of the conventional legacy spectrum database with the aim to enhance the self-organization capabilities of the typical wireless networks, such as cognitive radio network, WiFi as well as heterogeneous cell network.