Abstract: A radio communication device includes: a transmission/reception unit capable of spatially multiplexing signals to be transmitted to a plurality of counterpart devices with one frequency, and transmitting the signals at the same time, by using a hybrid beamforming method combining analog beamforming and digital precoding, the counterpart devices being counterpart radio communication devices; and a control unit to determine a number of transmission array(s) to be allocated to each of the counterpart devices and a number of transmission(s) of reference signal(s) to be transmitted to each of the counterpart devices on the basis of channel state information fed back from each of the counterpart devices.

Abstract: A base station (1) according to the present invention includes: a control unit (10) that allocates one or more layers per terminal for transmission to one or more terminals, and configures positions in a frequency domain and a time domain of reference signals of each of the layers on the basis of at least one of information indicating a position of each of the terminals and information indicating condition of each of channel between the transmission device and the one or more terminals; a processing unit (12-1 to 12-N) that arranges the reference signals of each of the layers in the frequency domain and the time domain on the basis of the positions in the frequency domain and the time domain configured by the control unit (10); and a precoding unit (13) and a transmitting unit (14) that perform space-division multiplexing on signals of one or more layers arranged by the processing unit (12-1 to 12-N), and transmit the multiplexed signals.

Abstract: A reception device includes an equalization processing unit including a linear filter unit and a nonlinear filter unit and performing equalization process on a reception signal; a linear propagation channel estimation unit making propagation channel estimation using a known signal included in a reception signal to calculate a filter coefficient of the linear filter unit; and a synchronization processing unit performing synchronization process of correcting frequency deviation based on a signal output by the equalization processing unit, and when a predetermined condition is satisfied after executing first equalization process of outputting a reception signal filtered by the linear filter unit to the synchronization processing unit, the equalization processing unit starts second equalization process that is an adaptive equalization process of outputting a result of addition of a reception signal filtered by the linear filter unit and a reception signal filtered by the nonlinear filter unit to the synchronizati

Abstract: A wireless communication apparatus includes a primary selection unit that selects a plurality of candidate terminals from among a plurality of terminals, based on signal-to-interference noise ratios of signals received from the plurality of terminals, a secondary selection unit that selects a plurality of transmission destination terminals from among the plurality of candidate terminals, based on channel estimate values of the candidate terminals, and a transmission processing unit that spatially multiplexes signals to be transmitted to the plurality of transmission destination terminals selected by the secondary selection unit, simultaneously on the same frequency.

Abstract: Provided is a method for filling a stem-side hollow area of an engine valve with metallic sodium. The method includes injecting melted metallic sodium into a cylinder having a larger diameter than an inner diameter of the hollow area of the engine valve, forming a solidified metallic sodium rod having a substantially uniform structure in the cylinder, inserting the metallic sodium into the hollow area of the engine valve through a nozzle having a small diameter, and sealing the engine valve.

Abstract: The base station allocates, to one terminal, at least one transmission layer and allocates at least one resource block that is a minimum allocation unit of a communication resource in each transmission layer, to transmit a signal to the terminal, and includes processing units each associated with one of the transmission layers, the processing units being equal in number to the transmission layers. Each processing unit includes a reference signal generation unit to generate a reference signal to be used by the terminal in demodulation processing on a received signal, and an information processing unit to determine an arrangement of the resource block in which to transmit the reference signal to the terminal, based on at least one of a state of a channel between the base station and the terminal or information on the resource block to be used in transmission of the reference signal in an adjacent cell.

Abstract: A base station includes: a control unit that allocates one or more layers per terminal for transmission to one or more terminals, and configures positions in a frequency domain and a time domain of reference signals of each of the layers on the basis of at least one of information indicating a position of each of the terminals and information indicating condition of each of channel between the transmission device and the one or more terminals; a processing unit that arranges the reference signals of each of the layers in the frequency domain and the time domain on the basis of the positions in the frequency domain and the time domain configured by the control unit; and a precoding unit and a transmitting unit that perform space-division multiplexing on signals of one or more layers arranged by the processing unit, and transmit the multiplexed signals.

Abstract: A wireless communication apparatus includes a primary selection unit that selects a plurality of candidate terminals from among a plurality of terminals, based on signal-to-interference noise ratios of signals received from the plurality of terminals, a secondary selection unit that selects a plurality of transmission destination terminals from among the plurality of candidate terminals, based on channel estimate values of the candidate terminals, and a transmission processing unit that spatially multiplexes signals to be transmitted to the plurality of transmission destination terminals selected by the secondary selection unit, simultaneously on the same frequency.

Abstract: Provided is a method for flaw inspection of a stem joint of a valve including: an internal flaw inspection step including causing a flaw detection probe to be disposed so as to face upward in water in a tank in an ultrasonic inspection chamber, holding a valve in such fashion as to cause the tip to face the flaw detection probe, and inspecting for a flaw at the interior of the stem joint; and a surface flaw inspection step including causing a flaw detection probe to be disposed horizontally in an eddy-current inspection chamber, holding a valve in such fashion as to cause the side face of a stem of the valve to be close to and facing the flaw detection probe, inspecting for a flaw on the surface of the stem joint while the flaw detection probe and the valve are made to engage in mutual rotation.

Abstract: A wireless communication apparatus, for example a wireless base station that spatially multiplexes data for transmission, includes plural array antennas and a beam shape controller that controls the array antennas to form beams of different shapes and each transmit signals for communication quality measurement in an area to be covered by the apparatus, and determines an initial value of a beam shape to be used in data transmission to a counterpart device that has received the signal for communication quality measurement, and after the initial value is determined, repeatedly executes processing to control the array antennas to tentatively change a beam shape in use in data transmission to the counterpart device, and redetermine a beam shape to be used in data transmission to the counterpart device, based on communication quality measured when the post-tentative-change beam shape is used and communication quality measured when the pre-tentative-change beam shape is used.

Abstract: It is preferable that metallic sodium to be loaded to an engine valve used for an internal combustion engine such as automobile engine have high purity. However, conventionally, an organic solvent remaining in micropores on a surface of the metallic sodium have been hardly attracted attention. Provided is a method for purifying metallic sodium including steps of placing metallic sodium containing organic solvent in the micropores thereof in a melting tank which is sealed, and heating the melting tank under reduced pressure to vaporize and remove the organic solvent coating the metallic sodium.

Abstract: Provided is a method for filling a stem-side hollow area of an engine valve with metallic sodium. The method includes injecting melted metallic sodium into a cylinder having a larger diameter than an inner diameter of the hollow area of the engine valve, forming a solidified metallic sodium rod having a substantially uniform structure in the cylinder, inserting the metallic sodium into the hollow area of the engine valve through a nozzle having a small diameter, and sealing the engine valve.

Abstract: Provided is a wireless communication device, which is configured to: execute, for each of a plurality of counterpart wireless communication devices to be targets, first processing for determining a maximum number of assignable transmission streams based on transmission line quality information with respect to each of the plurality of counterpart wireless communication devices; execute, for each of the plurality of counterpart wireless communication devices, second processing for calculating a diversity order value of a single stream or each of a plurality of streams through use of the maximum number of transmission streams obtained by the first processing, and compare the calculated diversity order value of the single stream or each of the plurality of streams and a diversity order lower limit value set in advance to each other, to thereby determine a number of transmission streams; and determine the number of transmission streams obtained by the second processing as a finally-determined number of transmissio

Abstract: Provided is a method for flaw inspection of a stem joint of a valve including: an internal flaw inspection step including causing a flaw detection probe to be disposed so as to face upward in water in a tank in an ultrasonic inspection chamber, holding a valve in such fashion as to cause the tip to face the flaw detection probe, and inspecting for a flaw at the interior of the stem joint; and a surface flaw inspection step including causing a flaw detection probe to be disposed horizontally in an eddy-current inspection chamber, holding a valve in such fashion as to cause the side face of a stem of the valve to be close to and facing the flaw detection probe, inspecting for a flaw on the surface of the stem joint while the flaw detection probe and the valve are made to engage in mutual rotation.

Abstract: It is preferable that metallic sodium to be loaded to an engine valve used for an internal combustion engine such as automobile engine have high purity. However, conventionally, an organic solvent remaining in micropores on a surface of the metallic sodium have been hardly attracted attention. Provided is a method for purifying metallic sodium including steps of placing metallic sodium containing organic solvent in the micropores thereof in a melting tank which is sealed, and heating the melting tank under reduced pressure to vaporize and remove the organic solvent coating the metallic sodium.