Abstract: A scheduling apparatus and method are disclosed. An embodiment of the invention provides a scheduling apparatus that includes: a scheduling group classification unit that classifies user terminals located within a serving cell of a base station into a multiple number of scheduling groups by using large-scale fading information of the user terminals; a transmission power setting unit that sets the transmission power of the user terminals for each of the classified scheduling groups; a scheduling period setting unit that sets the scheduling period for each of the scheduling groups by determining a resource element usage proportion for each of the scheduling groups based on the data rate of each of the scheduling groups and determining the data rate expected for all user terminals; and a resource element allocation unit that allocates resource elements used for each of the scheduling groups according to each of the determined scheduling periods.

Abstract: A semiconductor system includes a controller operatively coupled to a semiconductor device, the controller being suitable in a training mode for receiving an external signal and a first data signal from an external device and for transmitting the received external signal and the first data signal to the semiconductor device; and the semiconductor device being suitable in the training mode for determining a level of a reference voltage in response to the first data signal, and for transmitting a second data signal to the controller by buffering the external signal based on the reference voltage without performing a termination operation during an output period of the second data signal, wherein the controller controls an enable timing of the external signal by receiving the second data signal.

Abstract: Provided is a method and an apparatus for uplink and downlink separated connections, wherein a terminal may establish a downlink cell association with a downlink base station, receive an identifier of an uplink base station providing an uplink from the downlink base station to the terminal through an established downlink, and establish an uplink cell association with the uplink base station using the identifier of the uplink base station, and the downlink base station may select the uplink base station from among base stations in a network based on an uplink reference signal and a bias factor.

Abstract: Provided is a method and an apparatus for uplink and downlink separated connections, wherein a terminal may establish a downlink cell association with a downlink base station, receive an identifier of an uplink base station providing an uplink from the downlink base station to the terminal through an established downlink, and establish an uplink cell association with the uplink base station using the identifier of the uplink base station, and the downlink base station may select the uplink base station from among base stations in a network based on an uplink reference signal and a bias factor.

Abstract: The present invention relates to an adaptive transmitting device using limited feedback information in a mobile communication system, and a method thereof. According to an exemplary embodiment of the present invention, when the base station transmits a pilot signal to the terminal, the terminal generates channel information by using the pilot signal, generates additional channel information from the channel information, and transmits the channel information and the additional channel information to the base station. The base station determines band allocation, power allocation, and modulation methods for each use by using received feedback information, and transmits modulated traffic data to the terminal according to the determined methods.

Abstract: The exemplary embodiment of the present invention provides a method of synchronizing a femtocell base station securing time synchronization of a femtocell base station by allowing the femtocell base station to transmit a symbol to a terminal belonging to the femtocell by performing the time synchronization with a preamble signal when the femtocell base station receives the preamble signal from the macrocell base station in an orthogonal frequency division multiple access (OFDMA) communication system in which a femtocell is present in a macrocell.

Abstract: Disclosed is a random access data transmission system and method using OFDMA. The system includes a scheduling ID into an access grant on a preamble for a random access, and transmits it together with an acknowledgment or a non-acknowledgment of the preamble, a base station uses the scheduling ID to notify the mobile station of a random access data transmittable time and a data transmission channel through a control channel, and the mobile station transmits a preamble in advance. After receiving a transmission assignment instruction corresponding to a scheduling ID through the control channel, the mobile station transmits random access data through an assigned channel.

Abstract: Provided is a method and an apparatus for uplink and downlink separated connections, wherein a terminal may establish a downlink cell association with a downlink base station, receive an identifier of an uplink base station providing an uplink from the downlink base station to the terminal through an established downlink, and establish an uplink cell association with the uplink base station using the identifier of the uplink base station, and the downlink base station may select the uplink base station from among base stations in a network based on an uplink reference signal and a bias factor.

Abstract: Provided are a method and a device for avoiding interference of an uplink in a macro cell within a heterogeneous cellular network system. A femtocell base station calculates a degree of the interference of the uplink in the macro cell, and determines whether the interference is strong. If the interference of the uplink in the macro cell is strong, the femtocell base station changes the order of a femtocell uplink frame and a femtocell downlink frame.

Abstract: Provided is a method and an apparatus for uplink and downlink separated connections, wherein a terminal may establish a downlink cell association with a downlink base station, receive an identifier of an uplink base station providing an uplink from the downlink base station to the terminal through an established downlink, and establish an uplink cell association with the uplink base station using the identifier of the uplink base station, and the downlink base station may select the uplink base station from among base stations in a network based on an uplink reference signal and a bias factor.

Abstract: The exemplary embodiment of the present invention provides a method of synchronizing a femtocell base station securing time synchronization of a femtocell base station by allowing the femtocell base station to transmit a symbol to a terminal belonging to the femtocell by performing the time synchronization with a preamble signal when the femtocell base station receives the preamble signal from the macrocell base station in an orthogonal frequency division multiple access (OFDMA) communication system in which a femtocell is present in a macrocell.

Abstract: Disclosed is a random access data transmission system and method using OFDMA. The system includes a scheduling ID into an access grant on a preamble for a random access, and transmits it together with an acknowledgment or a non-acknowledgment of the preamble, a base station uses the scheduling ID to notify the mobile station of a random access data transmittable time and a data transmission channel through a control channel, and the mobile station transmits a preamble in advance. After receiving a transmission assignment instruction corresponding to a scheduling ID through the control channel, the mobile station transmits random access data through an assigned channel.

Abstract: Provided are a method and a device for avoiding interference of an uplink in a macro cell within a heterogeneous cellular network system. A femtocell base station calculates a degree of the interference of the uplink in the macro cell, and determines whether the interference is strong. If the interference of the uplink in the macro cell is strong, the femtocell base station changes the order of a femtocell uplink frame and a femtocell downlink frame.

Abstract: The present invention relates to an adaptive transmitting device using limited feedback information in a mobile communication system, and a method thereof. According to an exemplary embodiment of the present invention, when the base station transmits a pilot signal to the terminal, the terminal generates channel information by using the pilot signal, generates additional channel information from the channel information, and transmits the channel information and the additional channel information to the base station. The base station determines band allocation, power allocation, and modulation methods for each use by using received feedback information, and transmits modulated traffic data to the terminal according to the determined methods.

Abstract: The present invention relates to a mobile communication system, and to a method for managing terminal paging in the system. According to the present invention, local IDs are each allocated to the respective multiple MTC terminals, and therefore trigger periods can be efficiently managed in a network. Further, the multiple MTC terminals can be grouped using the allocated local IDs, thus achieving advantages of an increased number of MTC terminals which can be managed in the network.

Abstract: The exemplary embodiment of the present invention provides a method of synchronizing a femtocell base station securing time synchronization of a femtocell base station by allowing the femtocell base station to transmit a symbol to a terminal belonging to the femtocell by performing the time synchronization with a preamble signal when the femtocell base station receives the preamble signal from the macrocell base station in an orthogonal frequency division multiple access (OFDMA) communication system in which a femtocell is present in a macrocell.

Abstract: The present invention relates to an adaptive transmitting device using limited feedback information in a mobile communication system, and a method thereof. According to an exemplary embodiment of the present invention, when the base station transmits a pilot signal to the terminal, the terminal generates channel information by using the pilot signal, generates additional channel information from the channel information, and transmits the channel information and the additional channel information to the base station. The base station determines band allocation, power allocation, and modulation methods for each use by using received feedback information, and transmits modulated traffic data to the terminal according to the determined methods.

Abstract: A semiconductor memory device includes a first core region and a second core region disposed along a first reference line parallel to a major axis, the first reference line connecting an input pad and an output pad; first and second cell blocks disposed in the first core region along the first reference line; third and fourth cell blocks disposed in the second core region along the first reference line; and a repeater positioned between the third and fourth cell blocks, and configured to receive data outputted from the first cell block or the second cell block, amplify the received data and transfer the amplified data to a second global input/output line. Reducing the number of needed global input/output lines leads to layout area reduction. Moreover, since repeaters are driven in read operations for a limited number of cell blocks, signal gain may be reduced, thus reducing overall power consumption.

Abstract: Disclosed is a random access data transmission system and method using OFDMA. The system includes a scheduling ID into an access grant on a preamble for a random access, and transmits it together with an acknowledgment or a non-acknowledgment of the preamble, a base station uses the scheduling ID to notify the mobile station of a random access data transmittable time and a data transmission channel through a control channel, and the mobile station transmits a preamble in advance. After receiving a transmission assignment instruction corresponding to a scheduling ID through the control channel, the mobile station transmits random access data through an assigned channel.

Abstract: Disclosed are an adaptive pilot symbol assignment method that flexibly controls the number of transmit antennas according to each user's moving speed, channel status, or user request, and assigns proper pilot symbols in the downlink of an OFDMA (Orthogonal Frequency Division Multiplexing Access) based cellular system; and a sub-carrier allocation method for high-speed mobile that allocates some sub-carriers to assign proper pilot symbols for ultrahigh-speed mobile users, and the rest of the sub-carriers to the other users to assign proper pilot symbols to the users, on the assumption that the ultrahigh-speed mobile users have a traffic volume almost insignificant to the whole traffic volume.