Identifying rogue GSM base stations by intercepting downlink beacon channels

摘要

System and methods and memory media for identifying a rogue base station. A receiver captures an input signal that includes a mixture of the rogue station's transmission and the transmission of a victim base station. The victim station's transmission is removed from the mixture. A plurality of channel signals are extracted from the residual signal. The channel signals are analyzed which of them are "valid", i.e., contain a GMSK-modulated GSM signal. The "valid" channel signals are low pass filtered and then analyzed to determine which of them corresponds to the beacon channel. Information identifying the rogue base station is extracted from the beacon channel.