Abstract: A system and method for performing remote calling through a first and a second mediator system connected for communication is are provided. The system includes a first mobile communication terminal connected to the first mediator system, and a second mobile communication terminal connected to the second mediator system, wherein the first communication terminal controls the second communication terminal through the first and second mediator systems so as to exchange communication data with a third mobile communication terminal.

Abstract: Apparatus and method for transmitting and detecting subchannel constitution scheme information in a multihop relay Broadband Wireless Access (BWA) communication system. The method includes determining a subchannel constitution scheme for fixing a start zone of BW-RS link according to channel information (e.g., channel condition information, interference, and mobility), transmitting determined subchannel constitution scheme information of the start zone using a FCH preamble, detecting physical channel signals of subchannel constitution schemes from the received FCH preamble, checking preset codes, and detecting the subchannel constitution scheme of the start zone using the detected physical channel signals of the subchannel constitution schemes and the codes. The subchannel constitution scheme of the BS-RS link can be adaptively applied based on the channel information.

Abstract: A method for transmitting a handover security context of a first access point, when an access terminal from a service cell of a first access point is connected to a packet access router, to a service cell of a second access point connected to the packet access router, is provided. The handover security context transmitting method includes confirming whether a handover confirmation message transmitted from the access terminal has a security context therein; when the handover confirmation message has a security context therein, confirming whether the security context has security-related information therein; when the security context has security-related information therein, confirming whether the security context has a traffic-related key or a pairwise master key; and transmitting an information instruction message including the security related information confirmed in the security context, the security-related information, the traffic-related key, and the pairwise master key through the PAR to the second AP.

Abstract: A method and apparatus for selecting a service path of a Mobile Station (MS) in a relay communication system. The method includes periodically transmitting, by a Base Station (BS), a preamble (or pilot) signal to the MS and Relay Stations (RSs) existing within a cell; measuring, by the RSs, a Signal-to-Interference and Noise Ratio (SINR) of a BS-RS link, and transmitting the measured SINR and the preamble (or pilot) signal to the MS; by the MS, measuring an SINR of each link using signals received from the BS and the RSs; and by the MS, computing throughput in consideration of the SINR of each link and frequency resources reused in the RSs existing within the cell, and selecting a service path having the highest throughput.

Abstract: A mobile communication terminal having QWERTY keys and a method for outputting Dual Tone Multi-Frequency (DTMF) signals thereof are disclosed. The user inputs information including alphabetic characters that is requested by a directory system, while viewing the alphabetic characters marked on the QWERTY keys. The mobile communication terminal outputs DTMF signals of symbols marked on the input QWERTY keys identical to the DTMF signals of the corresponding symbols of keys arrayed in a conventional 3×4 key array format. The alphabetic keys of the QWERTY keys output DTMF signals identical to those of the keys of the 3×4 array format in an alphabet input mode. Therefore, the user can easily input information requested by the directory system while viewing the symbols marked on the QWERTY keys, without requiring the user to memorize the array of alphabetic characters of the 3×4 key array format.

Abstract: A method for signal reception in a Multiple-Input-Multiple-Output (MIMO) communication system is provided. The method enhances the efficiency of signal reception in the MIMO system and simplifies the algorithms of signal reception and soft decoding metrics generation. In other words, soft decisions are generated according to correlations between metrics corresponding to least reliable bits based on MMSE linear estimation and noise variance estimation is provided to improve performance when an error is generated in channel matrix H estimation.

Abstract: A method and apparatus for receiving data in a communication system is disclosed. Receiving a first signal from a transmitter, a first canceller cancels from the received first signal a second signal desired to be received from the transmitter. A second canceller detects and cancels an interference signal from the second signal-canceled first signal. A calculator calculates a Log Likelihood Ratio (LLR) of the interference signal-canceled first signal.

Abstract: A system and method for transmitting a traffic indication message in a Broadband Wireless Access communication system. A base station (BS) transmits the traffic indication message to mobile subscriber stations (MSSs). The traffic indication message includes information on a number of MSS groups and information on a number of traffic indication indexes, each of the MSS groups includes a predetermined number of MSSs, and each of the traffic indication indexes is assigned to each of the MSS groups, and includes a bitmap including a predetermined number of bits. The predetermined number of bits is identical to the number of the MSSs included in each of the MSS groups, each of the predetermined number of the bits is assigned to each of the MSSs included in each of the MSS groups, and represents operation instruction information for each of the MSSs.

Abstract: A method for allocating a band Adaptive Modulation and Coding (AMC) channel in a wireless communication system that divides a full frequency band into a plurality of subcarrier bands and includes subchannels, each of which is a set of a predetermined number of neighbor subcarrier bands. Upon recognizing a need for a band AMC channel, a subscriber station (SS) sends a request for allocation of the band AMC channel to a base station (BS). Upon receiving the band AMC channel allocation request, the BS determines if it can allocate the band AMC channel requested by the SS, considering a resource situation of the BS, and transmits information on the determination to the SS.

Abstract: Disclosed is a method for establishing a call connection in a wireless terminal, which can make a call connection using one line number when a call connection fails through another line number in a wireless terminal subscribing to a service in which the portable terminal uses two line numbers. The method includes receiving call release signals from a mobile switching center with respect to a call request of the wireless terminal; reattempting the call request in the wireless terminal with respect to the mobile switching center using a line number having priority, when the call release signal is received from the mobile switching center to the wireless terminal; and assigning resources from a resource pool used for another purpose so as to establish the call connection to the line number having priority when the mobile switching center receives the call request, which uses the line number having the priority, from the wireless terminal again.

Abstract: Disclosed is a method and system for transferring and applying a floor control scheme when a Push-To-Talk (PTT) over Cellular (PoC) session is established between PoC clients supporting various types of floor control schemes (e.g., media burst control schemes). According the method and system, when a PoC client providing Open Mobile Alliance PoC multimedia communication service supports a plurality of floor control schemes and there is no floor control scheme appointed to be supported in a session, a floor control scheme requested by a PoC session establisher is transferred through a PoC session establishment procedure and is applied to the session.

Abstract: Provided are a system for establishing and managing a Push To Talk (PTT) over Cellular (PoC) session between PoC clients supporting various media types, a method thereof, and a User Equipment (UE) therefor. When a PoC client performing an Open Mobile Alliance (OMA) PoC multimedia call service supports a plurality of media types, and media types supported by PoC clients are not common, a PoC session can be established to support only media types set to be transmitted in a first response message after the session is established. In addition, a method of efficiently managing a session by updating the session when a newly supported media type is provided or when a recipient of an existing media type is changed is suggested.

Abstract: A wireless packet data system efficiently manages a location of a packet call in a radio environment. A mobile station transmits a location registration message to a target BSC when moving to the target BSC adjacent to a source BSC. Upon receipt of the location registration message, the target BSC transmits a location update message for updating a location of the mobile station to a centralized database. Upon receipt of the location update message, the centralized database updates dormant state information for the mobile station to connect the target BSC to the source BSC. The centralized database transmits a location update result message indicating complete update of the dormant state information to the target BSC.

Abstract: Provided is a method for preventing excessive handovers in a mobile communication system. In the method, a periodic measurement report message is transmitted from a mobile terminal to a network. The network determines, on the basis of the measurement report message from the mobile terminal, whether a handover of the mobile terminal needs to be performed. Thereafter, the network transmits a Handover_Command message to the mobile terminal if the handover of the mobile terminal needs to be performed. Upon receipt of the Handover_Command message, the mobile terminal performs a handover to a target handover cell according to the Handover_Command message, transmits a Handover_Complete message to the network, and transmits a first measurement report message including neighboring cell information set to Null from the mobile terminal to the network after the transmission of the Handover_Complete message.

Abstract: Provided is an apparatus and method for power allocation in a Space Division Multiple Access (SDMA) system. The apparatus includes an encoder, an antenna weighting calculator, and an antenna. The antenna weighting calculator divides a transmission power of a Base Station (BS) by number of Mobile Stations (MSs), fixedly distributes the divided transmission powers to the MSs, calculates a surplus power of each MS, sums up the calculated surplus power to thereby calculate a total surplus power, calculates a power per MS needed for an MPR one level higher, determines whether there is an MS whose power needed for a next level MPR is smaller than the total surplus power, and additionally allocates the total surplus power when there is the MS.

Abstract: Disclosed is a method for processing a burst by a receiver in a wireless communication system having the burst, which includes at least one Protocol Data Unit (PDU). The method includes performing error checking of a first PDU header from among received bursts; performing error checking of a second PDU header when an error is detected in the first PDU header; and detecting the second PDU header by sequentially performing error checking from an address after the first PDU header when an error is detected in the second PDU header.

Abstract: Disclosed is a sliding module for a portable terminal having a first housing, and a second housing slidably assembled to the first housing to be opposed to the first housing through the sliding module, thereby partially opening or closing the first housing. The sliding module includes a sliding guide mounted on one of the first and second housings; a pair of stopper members mounted on the sliding guide at the opposite ends of the sliding guide, respectively; a pair of sliding members mounted on the other of the first and second housings, the sliding members being slidably engaged with the sliding guide; and a pair of ground members engaged with the sliding members to wrap the sliding members, respectively. When the second housing is located at a position of opening or closing the first housing, the ground members contact the stopper members, thereby being electrically connected with the stopper members.

Abstract: A method for determining a handoff of a mobile station (MS) in a mobile communication system. In the method, a serving base station (BS) measures a level of a first uplink signal by monitoring an uplink to the MS. The serving BS receives a level of a second uplink signal, measured and reported by at least one neighbor BS. The serving BS determines a handoff for the MS considering the level of the first uplink signal and the level of the second uplink signal.

Abstract: Disclosed are an apparatus and method for removing noise contained within a usable frequency band of a mobile communication terminal. The apparatus includes a multiplier for multiplying a main clock of the mobile communication terminal by a predetermined integer to generate a reference signal; a multiplexer for multiplexing parallel signals, the parallel signals being transmitted to a peripheral device inside the mobile communication terminal, using the reference signal, and converting the parallel signals into serial signals; a demultiplexer for demultiplexing the serial signals to convert the serial signals into parallel signals; and a frequency divider for recovering the reference signal of the serial signals transmitted from the demultiplexer into the main clock.

Abstract: A traffic information display method includes creating a highest-level traffic information selection menu among traffic information categorized in multiple levels, and displaying the created traffic information selection menu, creating a low-level menu including associated travel speed data, and displaying the created low-level traffic information selection menu and repeating the creation of the low-level menu until the lowest-level menu is displayed.