Abstract: An antenna device includes an antenna substrate and a feed line substrate. The antenna substrate includes subarray antennas, feeding interfaces and a back surface. The subarray antennas are arranged parallel with an interval on a plane. Each subarray antenna includes antenna elements and first feed lines. The first feed lines feed signals from the feeding interface on back surface to the antenna elements. The feed line substrate is attached along back surface and includes second feed lines, first and second mode transformers. Each second feed line has one and other ends portions. Other end portion has wider width than one end portion. Each first mode transformer is located in one end portion and connected to the feeding interface. Each second mode transformer is located in other end portion. One end portions are arranged in a line with interval, and other end portions are alternately arranged across one end portions.

Abstract: An antenna device includes subarray antennas including antenna elements, feeding lines and feeding interfaces. At least one of the feeding lines includes a phase shifter which shifts phases of the signals feeding to corresponding antenna elements. The feeding lines feed signals to the antenna elements. Each feeding interface is connected to each of subarray antennas. The subarray antennas are arranged parallel to each other with an interval on a plane to be symmetrical about a central axis. The interval is less or equal than a free-space wavelength. The central axis is along with the center of two adjacent subarray antennas arranged at middle of the subarray antennas when the number of the subarray antennas is even. Moreover, the central axis is along with one subarray antenna arranged at the middle of the subarray antennas when the number of the subarray antennas is odd.

Abstract: A measurement apparatus includes an anechoic chamber, a DUT board, rotation units, and a feeding arm. The anechoic chamber has inner-walls. Each inner-wall is covered with a radio wave absorber. One of the inner-wall is a first wall with an aperture and the other inner-walls are second walls. The DUT board holds a first antenna to be measured with radiation property and a probe to detect a signal from the first antenna. A part of the DUT board is inserted into the anechoic chamber through the aperture opened in the first wall. One end of the feeding arm holds a second antenna radiating a radio wave to the first antenna in the anechoic chamber. Each rotation unit provides on each second wall and is selectively attached to the other end of the feeding arm for rotating the second antenna and for feeding to the second antenna.

Abstract: A transformer between waveguide and transmission-line includes a high-frequency circuit module, transmission-lines, a waveguide, and feed pins. The high-frequency circuit module has differential-pair terminals to input and output a differential signal. The transmission-lines are connected to the differential-pair terminals. The waveguide includes a first to third metal walls. The feed pins are connected to the transmission-lines inside of the waveguide. The feed pins have a first distance of approximately (?g/2) from each other. One of the feed pins has a second distance of approximately (?g*(1+2 ?)/4) from the third metal plane. “?g” is a wavelength in the waveguide and “?” is an integer which is equal or larger than “0”. Each of the feed pins has a third distance of approximately (a/2) from the first or second wall. “a” is length of the waveguide along the third metal wall.

Abstract: The present application discloses, inter alia, a system for improving the aggregate throughput of a wireless local area network which includes: at least one access point that is equipped with at least one transceiver configured to simultaneously transmit and receive at multiple frequencies using multiple channels; and the access point being configured to acquire channel conditions of users and to pool sets of users on the channels based on the channel conditions.

Abstract: An antenna device includes a ground plane, an antenna element, and a metal wall. The antenna element is having a distance of (m×?/2-?/4) away from the ground plane, where “m” is an integer which is equal or larger than “1” and “?” is a wave length of operating frequency. The metal wall is surrounding the antenna element. One end of the metal wall is attached to along the ground plane. The other end of the metal wall is forming an aperture with a height from the ground plane. The height of the metal wall is (n×?/2), where “n” is an integer which is equal or larger than “m”.

Abstract: A system and method that addresses the issue of inducing and exploiting multi-user diversity in, e.g., a WLAN system in a fully distributed and opportunistic manner. In some embodiments, the system includes: an access point having a variable beamformer configured to fluctuate signal strength as perceived by stations within a range of the access point; and a plurality of stations having modified distributed-MAC protocol such as to be channel-aware and opportunistic.

Abstract: An antenna device includes subarray antennas including antenna elements and feeding interfaces. Each feeding interface is connected to each of subarray antennas. The subarray antennas are arranged parallel to each other with an interval on a plane to be symmetrical about a central axis. The interval is less or equal than a free-space wavelength. The central axis is along with the center of two adjacent subarray antennas arranged at middle of the subarray antennas when the number of the subarray antennas is even. Moreover, the central axis is along with one subarray antenna arranged at the middle of the subarray antennas when the number of the subarray antennas is odd.

Abstract: A reader that performs wireless communication with a tag inside a metal housing including a plurality of metal walls, the reader has an antenna which transmits and receives electromagnetic wave, a transmission control device that writes and/or reads information to/from the tag via the antenna, and a reflecting plate, reflecting the electromagnetic wave, and having a reflection phase different from that of the metal wall.

Abstract: In some embodiments, a system and method is disclosed for, among other things, reducing interference in a first wireless network from a second wireless network. In some embodiments, the method includes that an Interfered AP, which Interfered AP either itself receives interference or has a station in the Interfered AP's network that receives interference from an Interfering AP or from a station within the Interfering AP's network, selects how to reduce interference from a plurality of interference reduction methods—e.g., including transmit power control (TPC), channel switching (CS) and/or the like.

Abstract: The present application discloses, inter alia, a system for improving the aggregate throughput of a wireless local area network which includes: at least one access point that is equipped with at least one transceiver configured to simultaneously transmit and receive at multiple frequencies using multiple channels; and the access point being configured to acquire channel conditions of users and to pool sets of users on the channels based on the channel conditions.

Abstract: There is provided a magnetic field probe which includes: a probe body which is a coaxial cable wound to form a plurality of loop-like portions in planar view, the coaxial cable including an inner conductor, an insulator enclosing the inner conductor and an outer conductor enclosing the insulator; and a plurality of notches each of which is formed in each of the loop-like portions so that the outer conductor is divided to expose the inner conductor or the insulator, wherein: a plurality of outer conductor parts resulting from division by the notches are arranged to be electrically connected to each other, an one end of the inner conductor in the coaxial cable is connected to any one of the outer conductor parts; and winding directions of at least one of a pair of loop-like portions among the loop-like portions are reversed from each other in planar view.

Abstract: A short slot directional coupler includes a dielectric substrate having both surfaces each covered by a metal film, a first via-hole string and a second via-hole string, each of which has via-holes penetrating through the substrate, and formed so that a distance between the first via-hole string and the second via-hole string is narrow at a center of a length direction of the string and wider along directions of both ends of the string, and a pair of third via-hole strings each having via-holes penetrating through the substrate, and formed between parts adjacent to both ends of the first via-hole string and parts adjacent to both ends of the second via-hole string to form a first post-wall waveguide along with the first via-hole string and a second post-wall waveguide along with the second via-hole string.

Abstract: Radio communication apparatus includes unit dividing transmit data into first-and-second streams, unit subjecting first-and-second streams to serial-to-parallel conversion to obtain data signals, unit modulating data signals into OFDM-modulation signals corresponding to first and second streams using subcarriers, unit acquiring channel responses between communication and receiving apparatuses, unit computing singular values ?1(k) and ?2(k) of channel matrix corresponding to kth subcarrier in subcarriers, based on channel responses, unit assigning weights corresponding to singular values ?1(k) and ?2(k) to first-and-second streams where correspondence of weights to streams is different by subcarrier, unit multiplying, by each of assigned weights, OFDM-modulation signals corresponding to each of first and second streams, and acquire first-and-second signals corresponding to first-and-second streams, unit adding first-and-second signals to acquire added signals, unit subjecting added signals to inverse-Fourier t

Abstract: A wireless communication system which transmits and receives a signal by using a plurality of wireless apparatuses, comprising: a first wireless apparatus group having a plurality of transmitting apparatuses, each transmitting a wireless signal based on a first control signal, said first wireless apparatus group forming a first ad-hoc network between said transmitting apparatuses; and a second wireless apparatus group having a plurality of destination apparatuses, each receiving the wireless signal transmitted from said first wireless apparatus group, said second wireless apparatus group transmitting and receiving the wireless signal received by said destination apparatuses based on a second control signal, and said second wireless apparatus group forming a second ad-hoc network between said destination apparatuses different from said first ad-hoc network.

Abstract: One of objects of a wireless communication apparatus according to the present invention is to realize stable communication regardless of received signal strength indication and information amount. The wireless communication apparatus for communicating in an autonomous distributed wireless network includes a detection unit which generates a detection signal by detecting a first wireless signal from a first wireless apparatus; a wireless circuit which receives a second wireless signal relating to said first wireless signal, transmitted from a second wireless apparatus which received said first wireless signal; a signal estimation unit which estimates said detection signal and the received second wireless signal; a signal selector which selects either said detection signal or the received second wireless signal, based on an estimation result of said signal estimation unit; and a demodulator which demodulates the signal selected by said signal selector.

Abstract: In this second radio channel setting example, the grouping is done for each radio mobile stations 98 running on the same lane. A different radio channel is assigned to each group. Accordingly, this prevents the beam patterns using the same channel from intersecting with each other (interfering with each other). Actually, as shown in FIG. 10B, the pas or the pursuit does not occur between the radio mobile stations 98. Thus, the same radio channel is assigned to each radio mobile stations 98 running on the same lane so as to avoid the interference in the same radio channel. Hence, the same radio channel can be repeatedly used.

Abstract: The present invention has a N pieces of receiving antennas, a propagation path characterization estimator, a weight generator for interference canceller, an array processing interference canceller, a weight generator for signal estimator, a signal estimator, a transmission signal classification apparatus, and a decoding order decision apparatus. The antenna inference elimination circuit eliminates only signal component relating to transmission signal component which does not belong to groups. The signal estimator performs separation and decoding of the transmission signal belonging to the group. The transmission signal classification apparatus classifies the transmission signals from sets of the transmission antennas in which a cross-correlation value of the vector is larger than a threshold value, into one group, and classifies the transmission signal in which the cross-correlation value is smaller than the threshold value, into another group.

Abstract: One of objects of a wireless communication apparatus according to the present invention is to realize stable communication regardless of received signal strength indication and information amount. The wireless communication apparatus for communicating in an autonomous distributed wireless network includes a detection unit which generates a detection signal by detecting a first wireless signal from a first wireless apparatus; a wireless circuit which receives a second wireless signal relating to said first wireless signal, transmitted from a second wireless apparatus which received said first wireless signal; a signal estimation unit which estimates said detection signal and the received second wireless signal; a signal selector which selects either said detection signal or the received second wireless signal, based on an estimation result of said signal estimation unit; and a demodulator which demodulates the signal selected by said signal selector.

Abstract: A wireless communication system which transmits and receives a signal by using a plurality of wireless apparatuses, comprising: a first wireless apparatus group having a plurality of transmitting apparatuses, each transmitting a wireless signal based on a first control signal, said first wireless apparatus group forming a first ad-hoc network between said transmitting apparatuses; and a second wireless apparatus group having a plurality of destination apparatuses, each receiving the wireless signal transmitted from said first wireless apparatus group, said second wireless apparatus group transmitting and receiving the wireless signal received by said destination apparatuses based on a second control signal, and said second wireless apparatus group forming a second ad-hoc network between said destination apparatuses different from said first ad-hoc network.