Detection and Location Estimation of Transmitter Using the Gradient of the Power Gravity Point for Dynamic Spectrum Sharing

摘要

Mobile communication traffic is increasing yearly due to the spread of broadband services such as LTE, and demand is expected to increase for the fifth generation mobile communication system (5G) and beyond. For such advanced systems, more frequency bandwidth is required. The International Telecommunication Union (ITU) World Radio Communication Conference (WRC-19) was held and it is expected that an additional frequency band of 24Hz or higher will be allocated to 5G. However, since most of these frequency bands have already been allocated to other existing radio systems, the spectrum allocation scheme should be designed on the premise of sharing. In terms spectrum sharing, it is necessary to avoid interference. Since the location of existing system may change, the conventional spectrum sharing scheme defines the utilization area of existing system to be protected from interference (area protection). For higher spectrum sharing efficiency, the location of the existing system will be required to be estimated to be protected (point protection). The location estimation algorithm using the power gravity point estimates the location using simple information such as location and received power of sensors and therefore it is suitable for various and unspecified existing systems. On the other hand, it causes false estimations in the case of no and multiple transmitters. To solve the aforementioned problems, in this paper, the gradient of the power gravity point is calculated the region into sub-regions. Using the gradient value, existing systems are detected. In addition, in cases where the sub-region size is small enough for the spacing of transmitters, this algorithm can estimate multiple transmitters. The simulation results using ray-tracing data verify the validity of the proposed algorithm.