Abstract: Disclosed is a communication method using interference alignment in a wireless local area network (WLAN). An access point (AP) according to one embodiment may receive first channel information between a station associated with the AP and the AP and second channel information between the station and a neighboring AP to perform interference alignment in cooperation with the AP from the station, and perform interference alignment based on the first channel information and the second channel information.

Abstract: Disclosed is a communication method using interference alignment in a wireless local area network (WLAN). An access point (AP) according to one embodiment may receive first channel information between a station associated with the AP and the AP and second channel information between the station and a neighboring AP to perform interference alignment in cooperation with the AP from the station, and perform interference alignment based on the first channel information and the second channel information.

Abstract: A contactless cardiopulmonary signal estimation method and apparatus are provided. A cardiopulmonary signal estimation apparatus may estimate a cardiopulmonary signal of a user from a heartbeat signal and a respiratory signal of the user in response to movement of a chest based on a cardiopulmonary exercise of the user.

Abstract: Disclosed is a communication method using interference alignment in a wireless local area network (WLAN). An access point (AP) according to one embodiment may receive first channel information between a station associated with the AP and the AP and second channel information between the station and a neighboring AP to perform interference alignment in cooperation with the AP from the station, and perform interference alignment based on the first channel information and the second channel information.

Abstract: Disclosed is a communication method using interference alignment in a wireless local area network (WLAN). An access point (AP) according to one embodiment may receive first channel information between a station associated with the AP and the AP and second channel information between the station and a neighboring AP to perform interference alignment in cooperation with the AP from the station, and perform interference alignment based on the first channel information and the second channel information.

Abstract: Disclosed is a communication method using interference alignment in a wireless local area network (WLAN). An access point (AP) according to one embodiment may receive first channel information between a station associated with the AP and the AP and second channel information between the station and a neighboring AP to perform interference alignment in cooperation with the AP from the station, and perform interference alignment based on the first channel information and the second channel information.

Abstract: Provided are a data frame structure of a wireless communication system, which follows a sharing protocol which may be operated to coexist with a system that operates in an unlicensed spectrum, such as a WiFi system, and the like in the wireless communication system using a licensed spectrum such as an LTE system and an operation method of the system, and a terminal and a device of a base station for the operation.

Abstract: Disclosed are a wireless communication apparatus for reducing interference by a neighboring cell, and a method of reducing interference thereof. The method of reducing interference by a wireless communication apparatus includes: determining a neighboring small cell from one or more surrounding small cells adjacent to a small cell; allocating a communication resource to one or more users according to a channel state of the one or more users subscribing to the small cell; and transmitting data to the one or more users, to which the communication resource is allocated, by adopting one or more interference reducing methods for reducing interference by the neighboring small cell.

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: 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: Disclosed is a communication method using interference alignment in a wireless local area network (WLAN). An access point (AP) according to one embodiment may receive first channel information between a station associated with the AP and the AP and second channel information between the station and a neighboring AP to perform interference alignment in cooperation with the AP from the station, and perform interference alignment based on the first channel information and the second channel information.

Abstract: The present invention relates to an apparatus and a method for avoiding signal interference between access points (APs) in a non-license band, and more particularly, an interference avoidance apparatus and method between access points (APs) that avoid interference based on whether an overlapping basic service set (OBSS) is present, whether an overlapping operation channel between adjacent APs is used, whether it is possible to select a non-overlapping operation channel between adjacent APs, and the like.

Abstract: The present disclosure relate to a spectrum sensing method and a spectrum sensing device. The spectrum sensing method includes: (a) sampling a received signal: (b) calculating a first operation value relating to a strength of the received signal based on the sampled signal; (c) searching for a first frequency band having the largest correlation with an input signal based on the sampled signal; (d) calculating a first residual component signal by removing a signal component in the first frequency band from the received signal; (e) calculating a second operation value relating to a strength of the first residual component signal; and (f) determining whether the frequency band occupied in the received signal is present based on a relative value of the first operation value and the second operation value.

Abstract: Disclosed are signal transmitting apparatus and method capable of generating polarizations that can be controlled in real time by allocating weights to signals. A signal transmitting method for generating variable polarizations having any vector through a plurality of radiating elements vertical to each other includes: receiving an input signal and separating the input signal into a plurality of separated signals according to the number of radiating elements; and allocating weights for controlling vectors of the variable polarizations to each of the plurality of separated signals, wherein the vectors of the variable polarizations are represented by a vector sum of the plurality of separated signals allocated with weights.

Abstract: A communication method of a base station and a terminal based on interference alignment in a multi-cell multi-user multiple-input multiple-output (MIMO) interference channel and a method and apparatus of communication using interference alignment and block successive interference pre-cancellation in a multi-user MIMO interference channel. The base station may determine a precoding matrix to maximize a signal to interference and noise ratio (SINR) and a signal to leakage and noise ratio (SLNR) in the interference channel, and a terminal communicating with the base station may determine a decoding matrix to align interference. The transmitter including a multicell interference channel may calculate a rotation matrix for interference alignment, identify effective symbol vectors using the rotation matrix, and generate a transmit signal of a target transmitter to pre-cancel interference corresponding to a transmit signal of a neighboring transmitter.

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: Disclosed are a wireless communication apparatus for reducing interference by a neighboring cell, and a method of reducing interference thereof. The method of reducing interference by a wireless communication apparatus includes: determining a neighboring small cell from one or more surrounding small cells adjacent to a small cell; allocating a communication resource to one or more users according to a channel state of the one or more users subscribing to the small cell; and transmitting data to the one or more users, to which the communication resource is allocated, by adopting one or more interference reducing methods for reducing interference by the neighboring small cell.

Abstract: The present disclosure relate to a spectrum sensing method and a spectrum sensing device. The spectrum sensing method includes: (a) sampling a received signal: (b) calculating a first operation value relating to a strength of the received signal based on the sampled signal; (c) searching for a first frequency band having the largest correlation with an input signal based on the sampled signal; (d) calculating a first residual component signal by removing a signal component in the first frequency band from the received signal; (e) calculating a second operation value relating to a strength of the first residual component signal; and (f) determining whether the frequency band occupied in the received signal is present based on a relative value of the first operation value and the second operation value.

Abstract: Disclosed are a wireless communication method of improving frequency efficiency based on a channel function in a wireless communication system and an apparatus thereof. The wireless communication system using a digital modulation scheme, includes: a transmitting apparatus which modulates a data signal to generate a modulation symbol, generates a channel symbol function corresponding to the modulation symbol, combines the modulation symbol with the channel symbol function to generate a transmission symbol to transmit the generated transmission symbol through a transmission antenna; and a receiving apparatus which receives the transmission symbol through a reception antenna, estimates a channel symbol function included in the transmission symbol, and extracts the data signal based on the modulation symbol included in the transmission symbol.

Abstract: Disclosed is a method for managing network resources of a wireless terminal in a heterogeneous network environment and the method for managing network resources includes: searching for one or more networks which are accessible in the heterogeneous network environment; acquiring cycle information of the networks searched through the network searching; determining coexistence management cycles of the searched networks based on the cycle information; allocating one or more networks to be used in data transmission among the networks searched according to the coexistence management cycle and determining transmission management cycles of one or more allocated networks; and managing a resource of the searched network according to the coexistence management cycle and the transmission management cycle.