Abstract: A semiconductor memory device includes a memory cell array coupled to a plurality of word lines, a voltage generator generating a program voltage and first and second pass voltages in response to voltage generation control signals, an address decoder selectively applying the program voltage and the first and second pass voltages to the plurality of word lines in response to address decoder control signals, and a control logic controlling the voltage generator and the address decoder to perform a program operation.

Abstract: Disclosed herein are an apparatus and method for measuring a broadband Passive Intermodulation Distortion (PIMD) signal. The apparatus for measuring a broadband PIMD signal includes a Radio Frequency (RF) processing unit for combining one or more transmission signals into a single output signal and transmitting the output signal to a feeder so as to measure a PIMD signal and for generating a beat frequency signal using the PIMD signal received from the feeder, and a digital processing unit for transferring a control signal required so as to control the RF processing unit, receiving the beat frequency signal, and then measuring a location of a passive element in the feeder in which the PIMD signal has been generated by performing digital signal processing on the beat frequency signal.

Abstract: The present invention relates to a device and method for allocating a coexistence resource in an unlicensed band. The device according to the present invention comprises: a frame configuration unit for configuring a subframe in which data and a reference signal for a channel in an unlicensed band are allocated, and allocating a part of the symbols of the subframe as a coexistence resource; a signal detection unit for detecting a signal of another LTE system or Wi-Fi system during a transmission idle period where the coexistence resource is allocated; and a transmission processing unit which, when the signal of another system is detected during the transmission idle period, does not occupy a resource for the next subframe, and when the occupation of the coexistence resource by the another system has ended, occupies the resource for the next subframe.

Abstract: A wireless communication method may include performing, by a first system, channel monitoring of a first band, detecting a second system that uses the first band, determining whether the first system is to be used in preference to the second system, and allocating a radio resource of the first band to the first system based on whether the first system is to be used in preference to the second system.

Abstract: Provided is a method of generating a pilot pattern capable of perform adaptive channel estimation, and a method and apparatus of a base station and a method and apparatus of a terminal using the pilot pattern. The pilot pattern selects pilot symbol positions based on distances from pilots of previous orthogonal frequency division multiple access (OFDMA) symbols to a subcarrier position of a current OFDMA symbol in the frequency domain and the time domain, so that a low pilot density is maintained so as to effectively transmit data, and stable channel estimation performance can be obtained even in a bad channel environment. In addition, the minimum burst allocation size is determined according to the channel environment between the base station and the terminal, guaranteeing channel estimation performance suitable for the channel environment, and improving granularity, channel estimation latency, and channel estimation memory size.

Abstract: Disclosed are a method for generating a pilot pattern and an apparatus thereof. The method for generating a pilot pattern for MIMO antennas includes: determining a size of a slot that is an interval where a pilot pattern is repeated in a time domain and a frequency domain; determining a pilot inserting position of OFDMA symbols included in a slot determined for a first antenna; and determining a pilot inserting position of OFDMA symbols included in a slot determined for a second antenna, in order to have a sub-carrier different from a sub-carrier of the pilot inserting position of the OFDMA symbols included in the slot determined for the first antenna.

Abstract: Provided is an apparatus and method for managing a backup channel for cognitive radio communication that may group at least one device included in a cell served by a base station, and allocate backup channels for cognitive radio communication to the groups, based on location information and mobility of the groups.

Abstract: Provided herein is a method and apparatus for heterogeneous carrier aggregation, the method including calculating interferences regarding a plurality of interference paths between an adjacent cell and serving cell; determining weighted values for the plurality of interference paths in the serving cell; calculating an accumulated value (accumulated margin or accumulated interference) regarding the plurality of interference paths based on the weighted values in the serving cell; determining a component carrier to be used in the carrier aggregation based on the accumulated value calculated in the serving cell; and performing the carrier aggregation based on the component carrier determined.

Abstract: Provided is a hidden node detection method and apparatus in a wireless communication system, the apparatus including a sensing unit to sense a first communication device transmitting a data signal from among a plurality of communication devices sharing a wireless channel, a transmitter to generate a reception notification signal in response to the sensing, and transmit the reception notification signal to the a plurality of communication devices through a band identical to a transmission band of the data signal, and a controller to prevent a collision with the data signal transmitted from the first communication device through the wireless channel by delaying processing of a data transmission request when the data transmission request is input from a second communication device among the plurality of communication devices while maintaining the transmitting of the reception notification signal.

Abstract: Disclosed herein are a method and a system for performing initial ranging in a cognitive radio network The method for performing initial ranging in a cognitive radio network includes: detecting signals received in one or more ranging sections; estimating a tint time offset based on a correlation between subcarrier indices of the signals detected in the one or more ranging sections; estimating a second time offset based on correlations for the signals detected in the one or more ranging sections and a plurality of codes that are predetermined and detecting an initial ranging code among the plurality of codes; and estimating a time offset of a CPE performing initial ranging with the detected initial ranging code using the first time offset and the second time offset that are estimated.

Abstract: When a feature of the present invention is summarized, disclosed is a frame structure of transmitted and received data in a wireless communication system, including: a plurality of uplink subframes (UL) or downlink subframes (DL) for transmitting and receiving data; and a coexistence synchronization signal preamble for frequency coexistence among asynchronous cells.

Abstract: Disclosed is a resource allocating method of a base station, which includes receiving information on an existence signal of another base station or a coexistence frame in a transmission frame of another base station from a terminal, making time synchronization with another base station and frame synchronization with the coexistence frame of another base station coincide with each other, and allocating a signal transmission frame so as not to overlap the signal transmission frame in the transmission frame of another base station.

Abstract: Disclosed are an apparatus and a method for coexistence of heterogeneous services of a user terminal, which can enhance performance of a wireless communication network by simultaneously providing heterogeneous services such as an LTE-U service and a WiFi service to coexist without signal interference in unlicensed bands through effectively performing selection of a frequency band and selection of a transmission spectrum type in respective service modules of the user terminal.

Abstract: Disclosed are a method for generating a pilot pattern and an apparatus thereof. The method for generating a pilot pattern for MIMO antennas includes: determining a size of a slot that is an interval where a pilot pattern is repeated in a time domain and a frequency domain; determining a pilot inserting position of OFDMA symbols included in a slot determined for a first antenna; and determining a pilot inserting position of OFDMA symbols included in a slot determined for a second antenna, in order to have a sub-carrier different from a sub-carrier of the pilot inserting position of the OFDMA symbols included in the slot determined for the first antenna.

Abstract: A wireless communication method may include performing, by a first system, channel monitoring of a first band, detecting a second system that uses the first band, determining whether the first system is to be used in preference to the second system, and allocating a radio resource of the first band to the first system based on whether the first system is to be used in preference to the second system.

Abstract: A method and an apparatus for controlling transmit power of a CR device are provided. The method includes acquiring CR environment information regarding a licensed user or an unlicensed user occupying an adjacent channel or an adjacent cell of the CR device; determining a transmit power value of the CR device using the CR environment information; and generating transmit power control information including the transmit power value. The method and apparatus guarantee reliable communication of the CR device and minimize interference with the licensed user.

Abstract: Provided is an apparatus for controlling subcarrier spacing in a system supporting multiple frequency bands. The apparatus for controlling a subcarrier spacing comprises: an interference detection unit detecting interference over multiple frequency bands; a system parameter provision unit providing system parameters related to a subcarrier spacing between the multiple frequency bands—for example RF, FFT size, and channel bandwidth; a subcarrier spacing control unit controlling the subcarrier spacing such that the detected interference is reduced, on the basis of the system parameters. In a system operating with multiple bands, different subcarrier spacing can be applied by each band, thereby controlling interference occurring in each band.

Abstract: An exemplary embodiment provides a carrier aggregation apparatus including: a level assignment manager configured to perform management by classifying a license band allocated to a cognitive radio cell into a primary radio resource (PRR) level, and by classifying a shareable band obtained through a cognitive radio database or spectrum sensing into an auxiliary radio resource (ARR) level; a determiner configured to determine a quality of service (QoS) level of a communication service provided to the cognitive radio cell; and a service provider configured to allocate a frequency resource of the PRR level when the QoS level requires a first communication service, and to allocate a frequency resource of the ARR level when the QoS level requires a second communication service lower than the first communication service.

Abstract: A communication method for a cognitive radio (CR) base station in a multi-user multiple-input multiple-output (MIMO) CR communication system including the CR base station and CR terminals, may include calculating, from an interference channel, an orthogonal projection matrix to be used for removing interference on a primary user through use of a zero forcing (ZF) processing scheme, and obtaining a beamforming weight vector for each of the CR terminals, through use of the orthogonal projection matrix.

Abstract: Disclosed herein are an apparatus and a method of estimating a channel in consideration of a residual synchronization offset. The apparatus of estimating a channel in consideration of a residual synchronization offset includes: a channel estimating unit estimating the channel using pilots scattered over a plurality of OFDM symbols and calculating a first channel estimated value as the estimation result, in the case in which an OFDM symbol estimating the channel and an OFDM symbol compensating for the channel are different from each other; and a phase reflecting unit calculating a phase generated by the residual synchronization offset in proportion to a difference between a channel estimation time and a channel compensation time, reflecting the calculated phase in the first channel estimated value, and calculating a second channel estimated value as the reflection result.