A communication device including a receiving unit and a signal processing module having a simulation unit and a decision unit is provided. The receiving unit receives a first burst of a paging message provided from a base station. Base on a reference burst code and an estimated channel impulse response of the communication channel, the simulation unit generates a simulation burst. The decision unit then determines if the paging message is a dummy message in accordance with the first burst and the simulation burst. The decision unit requests the receiving unit to stop receiving the paging message once the paging message is determined to be a dummy message.