Abstract: A method for transitioning communications of a mobile subscriber station from a serving base station to a target base station includes receiving from the mobile subscriber station a transition request message having an identifier which identifies the mobile subscriber station, and transmitting a transition request notification message having the identifier to the target base station. The method further includes receiving a transition request notification response message having information relating to capabilities of the target base station, and transmitting a transition response message having the information to the mobile subscriber station.

Abstract: A handover control method in a broadband wireless access system is disclosed. In a broadband wireless access system supporting multiple frequency allocations, in which a serving base station controls a handover, the present invention includes the steps of receiving from a mobile subscriber station a handover request message including an identifier of the mobile subscriber station, transmitting a handover request notification message including the identifier of the mobile subscriber station to a handover target base station, receiving a handover request notification response message including information for frequency allocation supportable by the target base station, and transmitting a handover response message including the information for the frequency allocation to the mobile subscriber station. Accordingly, in the broadband wireless access system supporting the multiple FA, the present invention enables the handover between FAs within one cell or between FAs in different cells.

Abstract: A method of acquiring time synchronization and supporting method for the same are provided. The present invention enables early synchronization of a receiving side with a transmitting side by avoiding time delays that may result in detecting a current preamble signal. The current preamble signal is inserted with a uniform interval to allow the receiving side to tune its time synchronization with the transmitting side or measure a signal strength in the orthogonal frequency division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) wireless communication system. In an OFDM or OFDMA wireless communication system, the present invention includes modulating a number of reference signals for time synchronization acquisition in a receiving side using at least one of a number of subcarriers and continuously transmitting at least one reference signal modulated by at least one subcarrier to the receiving side during at least one symbol time.

Abstract: A method of acquiring time synchronization and supporting method for the same are disclosed. The present invention is suitable for a receiving side to be synchronized with a transmitting side at an early stage by settling a problem of consuming time in finding to read a current preamble signal inserted, with a uniform, interval in case that the receiving side tunes its time synchronization with that of the transmitting side or measures a signal strength in the OFDM or OFDMA wireless communication system. In an OFDM (orthogonal frequency division multiplexing) or OFDMA orthogonal frequency division multiple access) wireless communication system, the present invention includes the steps of modulating a plurality of reference signals for time synchronization acquisition in a receiving side via at least one of subcarriers and transmitting the at least one reference signal modulated by the at least one subcarrier to the receiving side continuously during at least one symbol time.

Abstract: The present invention relates to a method of performing handover and a method of supporting handover in a broadband wireless access system for minimizing service transmission delay during handover. The present invention discloses a technical feature that the mobile station determines the target base station for handover in consideration of information related to data transmission time necessary for transmitting data from the serving base station to the target base station.