Nec Corporation

Naoyuki Orihashi

Kenichi Maruhashi

Kenichi Hosoya

Masaharu Ito

Masahiro Tanomura

Yasuhiro Hamada

Shuya Kishimoto

Masatoshi Shimizu

An electronic circuit apparatus according an aspect of the present disclosure includes a substrate, an electronic circuit disposed on the substrate, and metal patterns and formed on the same surface as a surface on which the electronic circuit is disposed, the metal patterns and being provided so as to be in an electrically floating state, in which the metal patterns and are disposed at places where they have a specified distance from the electronic circuit.

Electronic circuit apparatus

Impedance optimization is difficult in microwave-band waveguide converters. To solve that problem, this waveguide converter is provided with the following: a waveguide provided so as to introduce microwaves to an antenna that performs input and output in a planar microwave circuit; a terminal waveguide that faces the aforementioned waveguide with the antenna interposed therebetween and connects to said waveguide so as to terminate same; and a conductor plate mounted so as to face the antenna. The conductor plate is electrically connected to at least part of the inside wall of the terminal waveguide.

Waveguide converter including a waveguide and antenna terminated by a terminal waveguide having an adjustable conductor plate

Antennaand radio communication apparatusinclude mount portionsand, flat proximity opposing surfacesand, and waveguide portionsandpenetrating through proximity opposing surfacesand, respectively. For example, in proximity opposing surfaceof radio communication apparatus, choke grooveis formed outside waveguide portion. With mount portionsandof antennaand radio communication apparatusabutted against and fixed to each other, proximity opposing surfacesandare set parallel to, and directly opposite to each other with a clearance interposed therebetween so that waveguide portionsand, opposite to each other and with a clearance, form a waveguide.

Connection structure between antenna apparatus and radio communication apparatus

A communication device(transceivers) transmits a training signal from its own transmitting antenna while performing beam scanning, and a communication device(transceivers) receives this training signal in a state where a quasi-omni pattern is generated in its own receiving antenna. Further, the devicetransmits a training signal in a state where a quasi-omni pattern is generated in the transmitting antenna, and the devicereceives this training signal by the receiving antenna while performing beam scanning. The deviceanddetects, from respective reception results, transmitting-antenna-setting candidates of the deviceand receiving-antenna-setting candidates of the device, and determines antenna-setting pairs (combinations of antenna-setting candidates). The above-described processes are also performed for a receiving antenna of the deviceand a transmitting antenna of the device. The deviceandcommunicates by using the obtained antenna-setting pairs. In this way, when radio communication is performed by using beam forming, the time necessary for finding and setting a beam direction is reduced, thereby reducing the transmission-disconnected time.

Control method of radio communication system, radio communication system, and radio communication apparatus

An antenna apparatusincludes a high-frequency output portionfor outputting a high-frequency signal, an antennaincluding a first excitation unitand a second excitation unit, the first excitation unitemitting a first linearly polarized wave according to the high-frequency signal output from the high-frequency output portion, the second excitation unitemitting a second linearly polarized wave that is orthogonal to the first linearly polarized wave at the same time with the first linearly polarized wave according to the high-frequency signal output from the high-frequency output portion, and a phase adjustment portionfor adjusting a phase of at least one of the high-frequency signal to be input to the first excitation unitand the high-frequency signal to be input to the second excitation unitin a range of change from 0 to 270 or more degrees.

Antenna apparatus and method of adjusting the same

When communication is to be performed between communication devices having a directivity control function, a plurality of antenna-setting pairs available for the communication are stored by an initial training, and the communication is started by using one of the plurality of antenna-setting pairs. When the communication quality is deteriorated, firstly, a training signal is transmitted while successively setting each one of the plurality of antenna-setting candidates determined in the initial training in a transmitting antenna of one of the communication devices (), and the training signal is received in a state where a quasi-omni pattern is generated in a receiving antenna of the other communication device (). In this way, in radio communication performing beam forming, it is possible to ensure the time synchronization between the communication devices when communication is disconnected or communication quality is deteriorated due to shielding or the like.

To suppress adverse effects caused by side lobes of an antenna array when an AWV to be used for communication is determined based on a transmission/reception result of a training signal. A first transceiver generates a fixed beam pattern and transmits a training signal. In that state, a second transceiver receives the training signal while scanning for the main beam direction, and thereby determines a plurality of direction of arrivals (DOAs). Next, the second transceiver receives the training signal in a state where the signal receptions from the plurality of DODs are restricted one by one (e.g., a null direction or a direction close to the null direction is fixed in the DOA), and calculates the change of the signal characteristics from that obtained in the first reception. The transceivers obtain and use at least one AWV having the main beam direction or a sub-beam direction close to the main beam pointing to one of the plurality of DOAs except for the DOA for which the change is lower than a predefined threshold.

Control method of wireless communication system, wireless communication system, wireless communication apparatus, and adjustment method of array weight vector

An array antenna apparatus includes a radio circuit; an array antenna that includes a plurality of antenna elements; feeder lines that connect the radio circuit to the respective antenna elements; and a delay circuit provided at each of one or more of the feeder lines. An amount of delay of the delay circuit is set so that the sum of a phase delay by the delay circuit and a phase delay due to a difference between a length of the corresponding feeder line and a predetermined reference length is an integer multiple of 360 degrees.

Array antenna apparatus having shortest wiring distance to antenna elements

A communication device(transceivers) transmits a training signal from its own transmitting antenna while performing beam scanning, and a communication device(transceivers) receives this training signal in a state where a quasi-omni pattern is generated in its own receiving antenna. Further, the devicetransmits a training signal in a state where a quasi-omni pattern is generated in the transmitting antenna, and the devicereceives this training signal by the receiving antenna while performing beam scanning. The deviceanddetects, from respective reception results, transmitting-antenna-setting candidates of the deviceand receiving-antenna-setting candidates of the device,and determines antenna-setting pairs (combinations of antenna-setting candidates). The above-described processes are also performed for a receiving antenna of the deviceand a transmitting antenna of the device. The deviceandcommunicates by using the obtained antenna-setting pairs. In this way, when radio communication is performed by using beam forming, the time necessary for finding and setting a beam direction is reduced, thereby reducing the transmission-disconnected time.

A channel response matrix is obtained by performing a training process between a transmitterand a receiverto obtain optimal signal phases of the antenna array. Next, a singular-value decomposition (SVD) process is performed to decompose the channel response matrix into a correlation matrix and eigenvalues. Next, a diagonal matrix having square roots of the eigenvalues as its components is obtained. Next, all but one of diagonal components included in the diagonal matrix are replaced with zeros, and optimal setting of the amplitudes and phases of signals to be applied to the antenna array (antenna weight vector) for use in wireless communication between the transmitter and the receiver is obtained based on a channel response matrix that is reconstructed by using the component-replaced diagonal matrix. In this way, when wireless communication is implemented by performing beam forming, the time necessary to find and set a beam direction can be reduced.

Control method of wireless communication system, wireless communication system, transmitting apparatus, and receiving apparatus

To suppress an adverse effect caused by side lobes of an antenna array when determining an AWV to be used in communication. A first communication device transmits/receives a training signal while scanning a beam pattern, and a second communication device receives/transmits the training signal with a fixed beam pattern. A primary DOD/DOA in the first communication device is determined based on the transmission/reception result of the training signal. Then, second round training is performed. In this point, the first communication device transmits/receives the training signal while scanning a beam pattern in a state where transmission to the primary DOD or reception from the primary DOA is restricted. A secondary DOD/DOA is determined based on the result of the second round training. An AWV corresponding to the primary DOD/DOA and an AWV corresponding to the secondary DOD/DOA are selectively used in communication between the first and second devices.

Control method of wireless communication system, wireless communication system, adjustment method of array weight vector, and wireless communication device

A first device transmits a training signal with a fixed beam pattern, a second device receives the training signal while scanning a beam direction, and then it obtains first AWVs each having a main beam or sub-beam beam direction in an incoming direction in the second device. Next, the first device transmits a training signal while scanning a beam direction, the second device receives the training signal with a fixed beam pattern, and then it obtains second AWVs each having a main beam or sub-beam direction in an emitting direction in the first communication device. The roles of these two devices are interchanged and similar processes are performed in order to obtain third and fourth AWVs, and then one of first AWV combinations from first and second AWVs and one of second AWV combinations from third and fourth AWVs are used for wireless communication between these devices.

Method of controlling wireless communication system and wireless communication system

Provided is a radio control method for a radio communication being performed in a beam direction that is set on the basis communication quality basis, including a step of acquiring a data string formed of at least a beam direction and communication quality in the beam direction; and a step of sequentially assigning a priority rank for setting the beam direction for performing the radio communication from the beam direction in which the highest communication quality is obtained, according to the data string. In the step of assigning a priority rank, no priority rank is assigned to the beam direction adjacent to the beam direction to which a priority rank has been already assigned or to the beam direction in the vicinity containing the adjacent beam direction.

Radio control method

A method of controlling a wireless communication system including a plurality of communication devices is disclosed. In the method, firstly, one of the communication devices establishes a fixed beam pattern and transmits a training signal, and another communication device receives the training signal while scanning a beam direction by changing the AWVs of an antenna array. Next, it obtains a data string describing a relation between an incoming direction and a received-signal characteristic at the other communication device based on a reception result of the training signal. Then, it obtains first AWVs with which a beam is formed in a plurality of incoming directions of the received signal based on the data string. The roles of these two communication devices are interchanged and similar processes are performed in order to obtain second AWVs, and then one of AWV combinations combining first and second AWVs are used for wireless communication between these communication devices.

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Tokyo, Japan

Naoyuki Orihashi