A method, device and system for arranging symbols to be sent in the frequency axis and for sending signals to a radio terminal inside an area using one or a plurality of carrier frequency bands, in a radio communication system with a hierarchical cell structure. The method includes detecting by a device at least one carrier frequency band signal pertaining to a transmission system other than that of its own station. A sending-symbol synchronization is detected based on at least one received signal upon detecting the carrier frequency band signal pertaining to the transmission system other than that of its own station. The signal is sent based on the derived symbol sending timing.