In this paper, we propose a stellite communications system for gathering data from a lot of observation points scattered over an ultra-wide area. The system configuration takes into account the requirements for a practical data gathering system. The main target of our system is reduced communication cost by using a narrow frequency band and the main feature os an economical data gathering using a group-modem composed of a multi-carrier multi-rate filter bank. We describe our system investigation for channel assignment methods, data gathering sequences, and channel interference suppression between narrow band carries.