Abstract: A method for seamless inter-frequency hard handover in a radio communication system is disclosed. The method for seamless inter-frequency hard handover includes the steps of: a) at a mobile station, blocking a first uplink carrier frequency used for communication, transmitting a direct sequence spread preamble signal through a second uplink carrier frequency for a short time, and continuously performing the communication through the first uplink carrier frequency; and b) at a target base transceiver station, acquiring an uplink synchronization of a mobile station based on the preamble before performing handover.

Abstract: A method for converting source data to a channel-modulated signal having a plurality of pairs of in-phase (I) and quadrature-phase (Q) data in a mobile station, wherein the mobile station uses at least one channel, includes the steps of: a) encoding the source data to generate at least one data part and a control part; b) generating at least one spreading code to be allocated to the channel, wherein each spreading code is selected on the basis of a data rate of the data part and the control part and spreading codes are selected so that two consecutive pairs of the I and Q data are correspondent to two points located on same point or symmetrical with respect to a zero point on a phase domain; and c) spreading the control part and the data part by using the spreading code, to thereby generate the channel-modulated signal. The method is capable of improving a power efficiency of a mobile station by reducing a peak-to-average power ratio in a mobile communication system.

Abstract: A method for performing a handover based on a compressed mode and a common frequency of neighbor cells is disclosed. The method for performing a handover includes the steps of: a) measuring the signal intensities of a common frequency of a source base station and a target base station, wherein the signal intensity is measured by the mobile station based on a downlink compressed mode; b) determining whether a handover is necessary or not, based on the signal intensities of the common frequency; c) if the handover is necessary, at the source base station, allowing the mobile station to perform intra cell hard handover from a frequency used for communication between the mobile station and the source base station to the common frequency; and then d) allowing the mobile station to perform a soft handover from the source base station to the target base station based on the common frequency.

Abstract: Information for different subscribers of a service with the same modulation and channel encoding method is transmitted by allocating radio resources in a wireless portable Internet system. Also, identifier information on the subscriber of a concurrently allocated radio resource is transmitted through common control information. Therefore, information for a plurality of subscribers coexists in a single radio resource block, and it can be easily transmitted. Since a subscriber station which has received downlink information can know to which radio resource block the information for the corresponding station is allocated through the subscriber identifier information transmitted as common control information, the subscriber station can access desired information by accessing a specific radio resource block to which information for the subscriber is allocated in the received frame.

Abstract: A method for converting source data to a channel-modulated signal having pairs of in-phase (I) and quadrature-phase (Q) data in a mobile station, wherein the mobile station includes: encoding the source data to generate at least one data part and a control pant; generating a spreading code to allocate to a channel, wherein each spreading code is selected on the basis of a data rate of the data part and the control part and spreading codes are selected so two consecutive pairs of I and Q data correspond to two points located on same point or symmetrical with respect to a zero point on a phase domain; and spreading the control part and the data part with the spreading code, to generate the channel-modulated signal. The method is capable of improving a power efficiency of a mobile station of a mobile communication system by reducing a peak-to-average power ratio.

Abstract: A method for performing a handover based on a compressed mode and a common frequency of neighbor cells is disclosed. The method for performing a handover includes the steps of: a) measuring the signal intensities of a common frequency of a source base station and a target base station, wherein the signal intensity is measured by the mobile station based on a downlink compressed mode; b) determining whether a handover is necessary or not, based on the signal intensities of the common frequency; c) if the handover is necessary, at the source base station, allowing the mobile station to perform intra cell hard handover from a frequency used for communication between the mobile station and the source base station to the common frequency; and then d) allowing the mobile station to perform a soft handover from the source base station to the target base station based on the common frequency.

Abstract: A method for seamless inter-frequency hard handover in a radio communication system is disclosed. The method for seamless inter-frequency hard handover includes the steps of: a) at a mobile station, blocking a first uplink carrier frequency used for communication, transmitting a direct sequence spread preamable signal through a second uplink carrier frequency for a short time, and continuously performing the communication through the first uplink carrier frequency: and h) at a target base transciever station, acquiring an uplink synchronization of a mobile station based on the preamble before performing handover.