A method and system for detecting a roaming location of a mobile network is provided to detect the roaming location in a systematic and efficient way. A wireless communication system in which a base station and a communication terminal can conduct wireless communication by detecting a usable wireless link and changing a wireless link used for the connection is also provided. The system deriving the proper timing using electrical or mechanical events having a predictable relationship with an optimal ventricular pacing timing signal. The improved particle beam treatment system optionally also includes more than two alternative particle beam paths. The at least one satellite uplink station is in communication with the plurality of satellites, and transmits the signal and alters a frequency of the signal based upon a location of the at least one active satellite to reduce a Doppler frequency shift when activating and deactivating the plurality of satellites.