Abstract: The present invention provides an overflow control method for frame synchronization of base stations in wireless communication network system. The wireless communication network system includes a radio network controller, a first base station, a second base station, and a mobile unit. The radio network controller transmits a plurality of data frames to the first base station and the second base station. The present invention includes the following steps. First, determine whether number of the plurality of data frames received by the second base station is larger than a judging storage capacity. Second, calculate an X and delete X of data frames from the second base station if the number is larger. The X is equal to the result of subtracting the judging storage capacity from the number. Meanwhile, detect a link quality between the mobile unit and the first base station.

Abstract: A method of relay transmission in a mobile communication system. The mobile communication system includes at least one base station and a plurality of user equipments (UEs). When one of the UEs attempts to send a message to the base station, this one of the UEs, referred to as a requesting UE, is capable of using the method of relay transmission to send messages to the base station via another one or more UEs, referred to as relay UEs. The method of relay transmission includes the following steps. First, a relay request confirmation procedure for the requesting UE and the relay UE is performed. Second, a base station confirmation procedure for the requesting UE, the relay UE, and the base station is executed. Next, an identity authentication procedure for the requesting UE, the relay UE, and the base station is performed. After that, a relay start confirmation procedure for the requesting UE and the relay UE is executed.