Abstract: 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.

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: A power amplifier of the present invention comprises MOS transistor (1) having a gate length of 180 nm or less, and output matching circuit (5) connected to a drain terminal of MOS transistor (1). Also, MOS transistor (1) is applied with voltage Vd_n normalized by a voltage value allowable in a DC state as a drain-source voltage, where Vd_n is in a range of 0.5 to 0.9. ZL (=RH+j·XL) represents a value equal to a load impedance when viewing the output matching circuit (5) from the drain terminal normalized by gate width W (mm) of MOS transistor (1), and a real part (RL) of the ZL is RL>0.64×Vd_n+0.19 (?·mm), and RL<0.64×Vd_n+1.73 (?·mm).

Abstract: In a phased array antenna radio communication apparatus including a plurality of antennas, a radio communication apparatus is provided which can reduce an influence of the local leak signals on the radiation direction of transmission signals. Local signal phase shifters 11-1 to 11-h are used to control phases of local signals to be input to quadrature modulators 13-1 to 13-h, and baseband signal phase shifters 12-1 to 12-h are used to control phases of baseband signals to be input to the quadrature modulators 13-1 to 13-h. The radiation direction of the local leak signals to be sent from transmission antennas 15-1 to 15-h can be controlled by the local signal phase shifters 11-1 to 11-h, and the radiation direction of the transmission signals can be controlled by both of the local signal phase shifters 11-1 to 11-h and the baseband signal phase shifters 12-1 to 12-h.

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 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: 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 reduce time to point a directional wireless portable terminal (WPT) to an access point (AP) when data is downloaded from the AP to the WPT, a user points the WPT to the AP, performs a first operation and transmits a request of authentication and download to the AP. The AP requests a server to perform the authentication and the download. The server transmits information on a current situation to the AP. The AP calculates time required until the download can be started based on content capacity and the like and transmits information on the calculated time to the WPT. The WPT displays countdown until the download can be started. During that time, the server performs the authentication and, if successful, delivers content to the AP. When the download can begin, the user performs a second operation and transmits a request of re-authentication and download to the AP.

Abstract: 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.

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: The present invention intends to improve communication efficiency between two communication apparatuses each engaged in the communication by full duplex communication method by using a surplus band of the one to transmission band of the other. A first bandwidth required by a first communication apparatus (A) at data transmission and a second bandwidth required by a second communication apparatus (B) at data transmission are presumed. Next, the first bandwidth presumed as mentioned is compared to a first bandwidth used which the first communication apparatus (A) currently uses and at the same time, the second bandwidth presumed as mentioned is compared to a second bandwidth used which the second communication apparatus (B) currently uses. The first bandwidth and the second bandwidth are then adjusted, and a third bandwidth which the first communication apparatus (A) uses at data transmission and a fourth bandwidth which the second communication apparatus (B) uses are determined.

Abstract: A bias circuit according to the present invention includes a resistor layer 2 which is placed above a substrate 1 and connected to a ground potential, and a conductor 4 for forming an inductor 5 placed above the resistor layer 2. Further, a manufacturing method of the bias circuit according to the present invention generates the resistor layer 2 above the substrate 1 and is connected to the ground potential, and generates the conductor 4 for forming the inductor 5 above the resistor layer 2. The present invention can provide a bias circuit and a manufacturing method of the bias circuit that enables easy integration on a semiconductor substrate and prevents parasitic oscillation.

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 radio communications device includes a transmitter, a receiver, a propagation detecting unit, and a symbol rate setting unit. The receiver has a plurality of antennas, a plurality of transmitting circuits, and a transmission signal processing circuit. The transmission signal processing circuit has a modulator, and modulates data input transmission data in modulator to output the modulated data as transmission signal to the transmitting circuits. The receiver has a plurality of antennas, a plurality of receiving circuits, and a reception signal processing circuit. The reception signal processing circuit has a demodulator, demodulates reception signals input from the receiving circuits in demodulator to generate reception data. The propagation detecting unit detects propagation state of radio waves. The symbol rate setting unit selects a symbol to be communicated from a plurality of symbol rates based on the detected propagating state and sets the selected symbol rate to the modulator and to the demodulator.