Abstract: A method and apparatus for allocating subcarriers in a broadband wireless communication system using multiple carriers are provided. In the wireless communication system where the total available frequency band is divided into a plurality of subcarriers and subchannels each are formed with a predetermined number of subcarriers, the subcarriers are grouped into subcarrier groups, subcarriers are selected from the subcarrier groups according to predetermined sequences, and the selected subcarriers are allocated as a subchannel to a cell in a predetermined time period.

Abstract: There is provided a method and apparatus for selecting an appropriate base station and an optimal data rate to provide a voice service and a data service based on a voice service load in a CDMA system. A base station transmits two pilot signals orthogonally spread with different orthogonal codes in association with its voice service load, and a mobile station estimates the voice service load based on a pilot power ratio.

Abstract: A communication method in a mobile communication system in which an access terminal transmits to an access network DRC information indicating a selected one of forward data rates requested by the access terminal is provided. The access network designates a DRC information length DRCLength indicating a number of slots where the DRC information is repeated and transmits the designated DRC information length to the access terminal. The access terminal gates transmission of DRC information to the access terminal at one time slot in every DRC information length received from the access network.

Abstract: An apparatus and method for gated transmission in a CDMA communication system. A mobile station in the CDMA communication system transmits a reverse pilot signal at a reverse gating rate different from a forward gating rate in a gated mode in a control hold state, and a base station transmits a forward pilot signal at the forward gating rate different from the forward gating rate in a gated mode.

Abstract: Disclosed is an apparatus for determining transmit power of an uplink frame transmitted from a subscriber station to a base station and transmitting data in a mobile communication system in which a downlink frame, transmitted from the base station to the subscriber station, and the uplink frame are time division-duplexed (TDD). The apparatus includes a receive power measurement unit for measuring receive power of signals received from the base station; a transmit power controller for determining the transmit power of the uplink frame from the receive power measured by the receive power measurement unit and information related to receptions of an uplink frame, which is received from the base station; and a transmission radio frequency processor for performing radio processing so that the uplink frame is transmitted according to the transmit power determined by the transmit power controller.

Abstract: There is provided a method and apparatus for selecting an appropriate base station and an optimal data rate to provide a voice service and a data service based on a voice service load in a CDMA system. A base station transmits two pilot signals orthogonally spread with different orthogonal codes in association with its voice service load, and a mobile station estimates the voice service load based on a pilot power ratio.

Abstract: Disclosed are an apparatus and a method for generating a preamble signal for cell identification in an OFDM mobile communication system. The method includes the steps of generating a Walsh code symbol for a cell identification by combining Walsh codewords having a predetermined length and generating the preamble signal through multiplying the Walsh code symbol by a pseudo noise (PN) code having a length identical to a length of the Walsh code symbol.

Abstract: Disclosed is a method for controlling downlink power transmitted from a base station to subscriber stations in a mobile communication system employing an Orthogonal Frequency Division Multiple Access (OFDMA) scheme, in which data is carried from the base station to the subscriber stations by subchannels to each of which a plurality of subcarriers are assigned. The method includes the steps of receiving from the subscriber stations channel condition information of each of the subchannels together with information related to a subcarrier having a channel condition below a threshold from among at least one subcarrier included in each of the subchannels; calculating transmission power for each of the subchannels based on the received information; and transmitting each of the subchannels with the calculated transmission power, excluding the subcarrier having a channel condition below the threshold.

Abstract: A radio communication system divides an entire frequency band into a plurality of subcarrier bands, forms a symbol from signals on the subcarrier bands, forms a frame from a plurality of symbols, transmits a pilot signal within symbols in a predetermined position of the frame, and transmits a data signal within symbols other than the symbols for transmitting the pilot signal. A transmitter generates the pilot signal, performs an inverse fast Fourier transform (IFFT) on the pilot signal by applying an IFFT size which is less than an IFFT size applied to the data signal, and transmits the IFFT-processed reference signal to a receiver.

Abstract: A wireless communication system that divides an entire frequency band into a plurality of subcarrier bands and includes a plurality of subchannels, each of which includes a number of subcarrier bands. The number of subcarrier groups is equal to the number of the base stations included in the system and are generated by classifying the subcarrier bands in a period. For a particular base station, corresponding subcarrier bands are detected from each of the groups according to a sequence. The subcarrier bands detected from each of the groups are assigned as a subchannel for the particular base station. Further, the indexes of the subcarrier groups to which each of subcarriers constituting a subchannel belongs are changed whenever the subchannel is assigned, so as to acquire the desired diversity gain.

Abstract: A method for transmitting reference signals in a radio communication system in which a frequency band is divided into a plurality of sub-frequency bands. The reference signals are transmitted through at least one of the plurality of sub-frequency bands, and data signals are transmitted through the plurality of sub-frequency bands except for the at least one of the plurality of sub-frequency bands. The method includes the steps of: determining a reference signal pattern representing positions of the at least one of the plurality of sub-frequency bands through which the reference signals are transmitted in consideration of a preset time and a preset bandwidth; generating the reference signals using a PN code and a Walsh code; and transmitting the reference signals through the sub-frequency bands corresponding to the reference signal pattern.

Abstract: A radio communication system divides an entire frequency band into a plurality of subcarrier bands, forms a symbol with signals on the subcarrier bands, forms a frame with a plurality of symbols, transmits a pilot signal within symbols in a predetermined position of the frame, and transmits a data signal within symbols other than the symbols for transmitting the pilot signal. A transmitter allocates subcarriers through which the reference signal is transmitted, wherein the subcarriers are allocated to have an exclusive relation with subcarriers through which reference signals of other transmitters are transmitted, generates the pilot signal, performs an inverse fast Fourier transform (IFFT) on the pilot signal by applying an IFFT size which is less than or equal to an IFFT size applied to the data signal, and transmits the IFFT-processed reference signal to a receiver.

Abstract: A method for increasing a network throughput of a cellular wireless packet network by controlling loading on a transmission frame in a cellular wireless packet network. In the method, transmission data are mapped to a transmission frame to be transmitted in a cellular wireless packet network in which a plurality of base stations and a plurality of mobile stations transmit packet data to each other. The method includes the steps of: dividing the transmission frame into a plurality of transmission groups each of which includes at least one slot; and constructing the transmission frame by allocating data with different loadings to the divided transmission groups.

Abstract: A forward link power control device for a mobile communication system supporting a transmission diversity function. The power control device comprises a base station device and mobile station device. The base station device transmits a traffic signal via at least two antennas, switches the traffic signal to be transmitted to any one of the two antennas based on a power control group period, and equally controls transmission power of the traffic signal being transmitted to the antennas according to power control information received via a reverse link.

Abstract: An method and apparatus for transmitting ranging information from at least one base station to subscriber stations and generating a ranging signal by the subscriber station using received ranging information in a Broadband Wireless Access (BWA) communication system including a plurality of neighbor cells and a plurality of the subscriber stations located in each cell region. A first code generator generates a first code using different first code information received from the base stations in the neighbor cells allocated the first code information. A second code generator generates a second code using second code information received by each of the subscriber stations existing in cell regions of the neighbor cells. A ranging signal generator generates a new ranging signal by combining the first code with the second code.

Abstract: A two-dimensional subchannel assigning method and apparatus in a time-frequency domain where a plurality of subcarriers are arranged along a time domain with a plurality of symbols and along a frequency domain with a plurality of subbands in an OFDM communication system. In the subchannel assigning method, the plurality of subcarriers are divided into a plurality of frequency bands and the frequency bands are grouped into the subbands. A plurality of groups are generated by dividing each of the subbands in the frequency domain by the number of the symbols in the time domain. Subcarriers selected from the respective groups in each of the subbands are assigned as an AMC subchannel to which an AMC scheme is applied.

Abstract: Disclosed is a method for handing-off a mobile station receiving packet data over a second channel from a first base station system (BSS) to a second BSS by a base station controller (BSC) in a system in which the mobile station communicates with the first BSS and the second BSS adjacent to the first BSS through a first channel for transmitting a control message, and the mobile station communicates with the first BSS through the second channel for transmitting the packet data. In the method the mobile station measures receiving strengths of pilot channels transmitted from the first BSS and the second BSS, and transmits the measured receiving strengths to the BSC through the first BSS and the second BSS. The first and second BSSs each calculate available transmission power allocable to the second channel and transmits the calculated available transmission power to the BSC.

Abstract: Disclosed is a method for assigning packet data to be transmitted to a radio packet data channel of a base station system in response to a packet traffic transmission request for a plurality of mobile stations in a mobile communication system. The method comprises collecting the packet traffic transmission requests of the radio packet data channel for the mobile stations; selecting at least one of the mobile stations from the collected packet traffic transmission requests; transmitting to the selected mobile station a channel assignment message including information about a data rate, data transmission durations of the radio packet data channel and start points of the data transmission durations for the selected mobile station; and transmitting the packet data to the selected mobile station at the start time of the data transmission durations at the data rate.

Abstract: A wireless communication system that divides an entire frequency band into a plurality of subcarrier bands and includes a plurality of subchannels, each of which is a set of a predetermined number of subcarrier bands. As many subcarrier groups as the number of the base stations are generated by classifying the subcarrier bands in a predetermined period. For a particular base station, corresponding subcarrier bands are detected from each of the groups according to a predetermined sequence. The subcarrier bands detected from each of the groups are assigned as a subchannel for the particular base station.

Abstract: A method is provided of continuously transmitting user data on a reverse common channel in a mobile communication system without a reverse dedicated channel. The user data is divided into a plurality of segmented messages if the user data is longer than a data segment in a frame of the reverse common channel. The plurality of segmented messages are then transmitted in the data segments of consecutive frames on the reverse common channel. The method further comprises determining whether a base station receives the segmented messages by receiving a response message indicating reception of the segmented messages. The common channel is preferably a power-controlled logical dedicated channel.