Abstract: An antenna apparatus 1 includes a high-frequency output portion 2 for outputting a high-frequency signal, an antenna 5 including a first excitation unit 3 and a second excitation unit 4, the first excitation unit 3 emitting a first linearly polarized wave according to the high-frequency signal output from the high-frequency output portion 2, the second excitation unit 4 emitting 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 portion 6 for adjusting a phase of at least one of the high-frequency signal to be input to the first excitation unit 3 and the high-frequency signal to be input to the second excitation unit 4 in a range of change from 0 to 270 or more degrees.

Abstract: An antenna apparatus includes: first high-frequency output means for outputting a first high-frequency signal; second high-frequency output means for outputting a second high-frequency signal having the same frequency component as that of the first high-frequency signal; first antenna means for emitting a right-hand elliptically polarized wave according to the first high-frequency signal output from the first high-frequency output means; second antenna means for emitting a left-hand elliptically polarized wave according to the second high-frequency signal output from the second high-frequency output means; and phase adjustment means for adjusting a phase of at least one of the first high-frequency signal output from the first high-frequency output means and the second high-frequency signal output from the second high-frequency output means.

Abstract: A communication quality test is performed for combinations between antenna setting candidates of a transmitting antenna of a first communication device (1) and a receiving antenna of a second communication device (2), and a list in which antenna-setting pairs are arranged according to the communication quality is created. If there are two or more antenna-setting pairs having the same antenna setting for one of the transmitting and receiving antennas, it is determined that an antenna-setting pair(s) ranked in a second or lower place is caused by a side-lobe and thus the list is updated by deleting that antenna-setting pair(s) from the list or lowering its priority rank in the list. The above-described steps are performed for a receiving antenna of the first communication device (1) and a transmitting antenna of the second communication device (2). An antenna-setting pair is successively selected from the updated antenna-setting-pair list and communication is performed.

Abstract: 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.

Abstract: A communication device 1 (transceivers 400) transmits a training signal from its own transmitting antenna while performing beam scanning, and a communication device 2 (transceivers 500) receives this training signal in a state where a quasi-omni pattern is generated in its own receiving antenna. Further, the device 1 transmits a training signal in a state where a quasi-omni pattern is generated in the transmitting antenna, and the device 2 receives this training signal by the receiving antenna while performing beam scanning. The device 1 and 2 detects, from respective reception results, transmitting-antenna-setting candidates of the device 1 and receiving-antenna-setting candidates of the device 2, and determines antenna-setting pairs (combinations of antenna-setting candidates). The above-described processes are also performed for a receiving antenna of the device 1 and a transmitting antenna of the device 2. The device 1 and 2 communicates by using the obtained antenna-setting pairs.

Abstract: 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 (400), 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 (500). 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A balun circuit comprising first through third CPW lines becoming signal I/O ports, a first differential transmission line for linking the central conductor of the second CPW line and the ground conductor of the first CPW line and for linking the ground conductor of the second CPW line and the central conductor of the first CPW line, a second differential transmission line for linking the central conductors of the first and third CPW lines and for linking the ground conductors of the first and third CPW lines, and a joint for connecting at least two ground conductors of the first through third CPW lines. The differential transmission line has a first line formed in a dielectric layer on a substrate, a second line arranged in the underlying layer, and an underlying line at a fixed potential arranged between the substrate and the second line.

Abstract: A channel response matrix is obtained by performing a training process between a transmitter 401 and a receiver 402 to 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.

Abstract: 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.

Abstract: 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.