In Japan, towards the Tokyo Olympics and Paralympics, the Japan Sports Agency has been founded, and policies related to training athletes and improving competitiveness are being promoted. To achieve these policies, many researches use AI technology to analyze sports data gathered by video cameras and IoT devices. To make effective use of those data, it is necessary to manage them with a unified time stamp. However, it is difficult to unify the time stamp because these devices are not linked to each other. To solve this problem, the time synchronization is often adopted manually, but it costs a lot of manpower. Therefore, in this research, we firstly organize the problems of time synchronization between video cameras and between video cameras and GNSS device by investigating existing researches. And then, we propose an efficient and highly accurate time synchronization technologies that can solve these problems.
