High Density Spectrum Sharing Method among Micro Operators considering Spectrum Database

In 5G, carrier independent operators such as micro operator and local 5G that arrange small cells with high flexibility and scalability attract attention. In these kinds of systems, it is assumed that multiple small cells with different operators share the same frequency band, hence it is necessary to arrange the small cells as densely as possible with avoiding co-channel interference. However, as the density of small cells increases, the degradation of communication quality due to inter-cell interference becomes a crucial issue. It is well known that highly accurate radio environment recognition can improve the spectrum sharing performance and measurement-based spectrum database (MSD) attracts attention for realizing the recognition. In this paper, we propose a method to increase the density of small cells while satisfying communication quality in multiple small cells jointly working with the MSD. The proposed method estimates the probability distribution of signal power-to-interference plus noise power ratio (SINR) by using the MSD. Based on the estimated probability distribution, the interference power control that satisfies the permissible outage probability of spectrum shared system is performed, maximizes the number of small cells that can share the spectrums.