Next generation satellite-routed sensor system (SRSS) is expected to provide disaster detection system with high real-time performance. By using satellite networks, SRSS realizes data collection from multiple sensor terminals deployed in a wide area. However, an efficient access control scheme is needed to achieve multiple access from numerous sensor terminals to the satellite with its limited bandwidth. Conventional research works propose a countermeasure to avoid data collisions at the satellite. However, they do not consider the situation that a significantly large number of sensor terminals communicate with the satellite anytime, which cause data collisions and decrease real-time performance. Therefore, in order to efficiently resolve these problems, we propose a new scheme which utilizes a divide and conquer approach for efficient bandwidth allocation. The effect of the scheme on the amount of time for allocating satellite bandwidth is also analyzed. The analysis clearly shows the advantage of our proposed scheme. Furthermore, numerical results demonstrate the effectiveness of our proposal.