Abstract: A device for controlling exposure of electromagnetic waves from a base station collects a power value received from at least one base station together with position information using a plurality of terminals in a controlled area; maps the received power value collected from the terminals on a plurality of subareas in the controlled area based on position information collected from the terminals; calculates a power density for respective frequency bandwidths in the respective subareas by using the received power value of the terminals provided in the respective subareas; and calculates a specific absorption rate of electromagnetic waves in a human body in the respective subareas by using a power density value for respective frequency bandwidths in the respective subareas.

Abstract: Disclosed is a method for allocating a resource of a terminal. The method includes: receiving downlink data from a base station; and allocating a resource for a device-to-device communication to a sub-frame by considering a hybrid ARQ (HARQ) transmission delay with respect to the received downlink data.

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 device of a communication system randomly selects a backoff counter at a contention window interval corresponding to a contention window size that is determined according to a backoff stage, attempts packet transmission, when the backoff counter becomes 0 while reducing the backoff counter, when a radio channel is in an idle status, and increases the contention window size while increasing the backoff stage by 1 according to a first predetermined condition. In this case, as the backoff stage increases, a contention window size has a concave down increasing form.

Abstract: The wireless power reception apparatus includes: a duty controller configured to calculate an amount of current of a transmission coil required for the wireless power transmission apparatus and control a duty cycle by using at least one of distance information between the wireless power transmission apparatus and the wireless power reception apparatus or load current information; a power converter configured to convert an effective load resistance according to the duty cycle; a wireless data transmitter configured to transmit a signal that requires a control of the calculated amount of current of the transmission coil to the wireless power transmission apparatus; and a reception resonator configured to receive a power according to the amount of current of the transmission coil controlled by the signal that requires a control of the amount of current of the transmission coil from the wireless power transmission apparatus.

Abstract: Provided is a wireless charging apparatus for performing wireless charging of an electronic device including a receiving coil located in a three-dimensional (3D) wireless charging zone using a plurality of transmitting coils arranged in the 3D wireless charging zone and at least one power source configured to supply a current to the plurality of transmitting coils.

Abstract: A phase measurement method in a microwave tomography system may include transmitting a first Tx frequency signal, receiving a signal corresponding to the first Tx frequency signal, and measuring a first phase value; transmitting a second Tx frequency signal separated by a predetermined discrete frequency from the first Tx frequency signal, receiving a signal corresponding to the second Tx frequency signal, and measuring a second phase value; calculating a first phase difference based on a difference between the first and second phase values; calculating a second phase difference based on the discrete frequency; and determining an unwrapped phase value through comparison between the first and second phase differences.

Abstract: Provided is a wireless power transmission device to reduce an electromagnetic wave except for a signal to be transmitted during wireless power transmission, the wireless power transmission device including a transmitter configured to generate a magnetic field by inputting a high-frequency power signal generated by a transmission circuit into a first coil, a receiver configured to generate an induced current by allowing the generated magnetic field to pass through a second coil, and a reducer configured to reduce a harmonic component of the high-frequency power signal using a third coil inserted on a path between the transmitter and the receiver.

Abstract: According to the exemplary embodiment of the present invention, a microwave tomography apparatus is an apparatus which measures microwave tomograph of a subject which is inserted into a medium container including: a plurality of antennas which is located in the medium container and transmits and receives an electromagnetic wave; a plurality of transceivers which, when a radio wave signal transmitted from one of the plurality of antennas is simultaneously received by the remaining antennas of the plurality of antennas, measures intensity and phase information of the radio wave signal received from the remaining antennas; and a controller which generates an image using the values measured by the plurality of transceivers.

Abstract: A device for controlling exposure of electromagnetic waves from a base station collects a power value received from at least one base station together with position information using a plurality of terminals in a controlled area; maps the received power value collected from the terminals on a plurality of subareas in the controlled area based on position information collected from the terminals; calculates a power density for respective frequency bandwidths in the respective subareas by using the received power value of the terminals provided in the respective subareas; and calculates a specific absorption rate of electromagnetic waves in a human body in the respective subareas by using a power density value for respective frequency bandwidths in the respective subareas.

Abstract: A method for reconstructing a dielectric image using electromagnetic waves, comprising: acquiring a measurement value of the electromagnetic waves; generating a matching system matrixes between the meshes; generating a smoothed dyadic Green's function matrix; generating an electromagnetic wave calculation value; calculating a misfit error between the acquired electromagnetic wave measurement value and the generated electromagnetic wave calculation value, and checking whether a change of the calculated misfit error satisfies a predetermined optimization determination condition; updating dielectric parameters at the meshes; and outputting a reconstructed dielectric image in the image reconstruction region.

Abstract: An exemplary embodiment of the present invention discloses a microwave signal processing method and apparatus which precisely focus a microwave onto a specific part of a biological tissue and rapidly images a temperature distribution in the biological tissue generated thereby.

Abstract: A wireless device of a communication system randomly selects a backoff counter at a contention window interval corresponding to a contention window size that is determined according to a backoff stage, attempts packet transmission, when the backoff counter becomes 0 while reducing the backoff counter, when a radio channel is in an idle status, and increases the contention window size while increasing the backoff stage by 1 according to a first predetermined condition. In this case, as the backoff stage increases, a contention window size has a concave down increasing form.

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: A method of providing an amount of exposure to electromagnetic waves, and a user terminal are provided. The method may include receiving a signal of each of a plurality of wireless services, extracting a measured electric field and a reference level of electric field strength from a signal associated with each of the plurality of wireless services, and determining an exposure index of each of the plurality of wireless services, based on the measured electric field and the reference level of electric field strength, the exposure index being measured outside a body of a user.

Abstract: Disclosed is a method for allocating a resource of a terminal. The method includes: receiving downlink data from a base station; and allocating a resource for a device-to-device communication to a sub-frame by considering a hybrid ARQ (HARQ) transmission delay with respect to the received downlink data.

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: An apparatus for self-examining whether a breast tissue is abnormal includes an examination checker configured to transmit a microwave to one side of an examinee's breast, receive the microwave that has passed through the breast and calculate a value in the microwave reception of the received microwave. Further, the apparatus includes a self-examination device configured to analyze the value in the microwave reception received from the examination checker and examines whether the breast is abnormal.

Abstract: Provided is an energy charging apparatus including a transponder configured to transmit and receive radio energy, and a resonator configured to transmit the radio energy transmitted from the transponder to at least one external device and transmit the radio energy received from the at least one external device to the transponder, wherein each of the transponder and the resonator is provided in a form of a single module.

Abstract: Provided is a specific absorption rate (SAR) provision method and a user terminal, the method including receiving a radio signal related to a radio service, determining a use pattern of a user sensed by a user terminal in response to the receiving, extracting a standard SAR for a body part of the user based on the determined use pattern, and determining a measured SAR for the body part of the user based on the extracted standard SAR and a transmission power of the user terminal.