Mitsubishi Denki Kabushiki Kaisha

Akio Iida

Kenji Itoh

Naofumi Yoneda

Moriyasu Miyazaki

Toshiyuki Horie

Shuji Nishimura

Yoshihiko Konishi

Tomoaki Fukushima

Ken'ichi Tajima

Hiroyuki Satoh

Koji Yamanaka

Yukio Ikeda

Takeo Shimizu

Hidetaka Yamauchi

Mitsuhiro Shimozawa

Shuji Urasaki

Noriharu Suematsu

Yoshio Inasawa

Kenichi Tajima

Masayuki Doi

Kazutomi Mori

Kenji Kawakami

Shigeru Makino

Izuru Naito

Hideyuki Oh-Hashi

Tetsu Ohwada

Yutaka Ozaki

Yoji Aramaki

Yutaka Shimawaki

Izuru Naitoh

Ichiro Shirokawa

Tomonori Sigematsu

Yutaka Simawaki

An antenna apparatus in which a combination of rectangular waveguidesandand a combination of rectangular waveguidesandare disposed bilateral symmetrically to each other, and a waveguide orthomode transduceris disposed above a waveguide orthomode transduceris provided. Therefore, the profile of the antenna apparatus can be reduced and the stability of installation of the antenna apparatus can be improved without impairing the electric characteristics of the antenna apparatus. Since the antenna apparatus has a bilateral symmetric structure, it excels in weight balance and offers stable performance from the viewpoint of mechanism.

Antenna device

The present invention aims at providing a rotary joint which is of a thin type and has broad band characteristics and which is low in loss and is excellent in power resistance as well. In order to attain the object, the rotary joint includes: first and second polarizers each having a common side terminal connected to a waveguide portion, and two branch side terminals through which two polarized waves orthogonal to each other inputted through the common side terminal are separately taken out; and the waveguide portion which has a rotatable connection portion, one end of which is connected to the common side terminal of the first polarizer and the other end of which is connected to the common side terminal of the second polarizer.

Rotary joint

The present invention includes: a first main waveguide; a T-branch circuitconnected thereto; a first low-pass filterconnected thereto; a band-pass filterconnected to the first T-branch circuit; a first converterconnected to the first low-pass filterfor converting transmission lines between a waveguide and a microwave integrated circuit; an amplifierconnected to the first converter and structured by the microwave integrated circuit; a second converterconnected thereto for converting transmission lines between a waveguide and the microwave integrated circuit; a second low-pass filterconnected thereto; a second T-branch circuitconnected to the second low-pass filter and the band-pass filter; and a second main waveguideconnected to the second T-branch circuit.

High frequency module and antenna device

An AC power source applies power to a primary coil that is provided in a fixed part. An AC current flowing through the primary coil induces electromotive force in a secondary coil that is provided in a movable part. The AC electromotive force induced in the secondary coil is converted by an AC/DC converter into DC power, which is input to a drive control section.

Antenna apparatus and waveguide rotary coupler

An antenna controller comprises an antenna beam control unit for controlling the direction of an antenna beam of an antenna, an inertial navigation system for acquiring motion information on a motion of the mobile body, an antenna beam direction calculation unit for calculating the direction of the antenna based on the motion information from the inertial navigation system to direct the antenna beam toward the geostationary satellite, a motion information acquisition unit for separately acquiring motion information on the motion of the mobile body, and a motion estimation unit for estimating a delay of the motion information acquired by the inertial navigation system based on the motion information acquired by the inertial navigation system and the motion information acquired by the motion information acquisition unit, and for estimating motion information to be sent to the antenna beam direction calculation unit in consideration of the estimated delay. The motion information acquisition unit has a 3-axis angular-velocity sensor. As an alternative, the motion information acquisition unit has a 3-axis magnetic bearing sensor.

Antenna control method and antenna controller

In a receiving and transmitting apparatus, a frequency of a direct digital synthesizer provided in a local oscillating circuit is controlled in order to reduce a frequency error, based on data of a frequency error detecting circuit. The direct digital synthesizer includes a digital operation circuit for inputting data designating the frequency and outputting an amplitude value of a periodic signal synchronous with a reference clock, and digital-analog converter for converting the amplitude value of the periodic signal to an analog signal.

Method and apparatus for communication and signal synthesis

A frequency synthesizer having reduced spurious components for use in a receiving and transmitting apparatus. The frequency synthesizer includes a direct digital synthesizer (DDS) for generating a first signal having a first frequency determined by channel setting data. The first signal is applied to a frequency divider to generate a divided signal having a divided frequency. The divided signal is applied to a frequency converter for shifting the divided frequency by a shift frequency interval to provide a reference signal having a reference frequency. The reference signal is applied to a phase locked loop (PLL) for generating a final signal having a predetermined frequency characteristic.

Frequency synthesizer using divided and frequency converted DDS signal

In order to further suppress unwanted waves which may occur when the frequency (flo) of a local oscillation wave is lower than the frequency (fin) of a signal wave, the local oscillation wave is in-phase distributed between unit mixers (2a) and (2b) whereas the signal wave is opposite-phase distributed through a 180 degree distributer (4) to the unit mixers (2a) and (2b). The unit mixers (2a) and (2b) execute frequency mixing of thus distributed local oscillation wave and signal wave, and supply the result through a BRF (16a) or (16b) into a 180 degree combiner (6). The 180 degree combiner (6) effects an opposite-phase combination of outputs of the BRFs (16a) and (16b), and outputs the result. Among the unwanted waves, harmonics of the local oscillation wave are suppressed by the opposite-phase combination, the signal wave is suppressed by virtue of the BRFs (16a) and (16b), and a mixed wave of the harmonics of the local oscillation wave and harmonics of the signal wave is suppressed by the in-phase distribution of the local oscillation wave and the opposite-phase distribution of the signal wave.

Balanced mixer, distributer and band rejection filter for use in same,

A variable divider in which a dividing number setting parameter can be set is provided in a reference oscillator. When a frequency setting parameter is selected so that a DDS will not output a spurious at a specified level or at a level higher than the specified level within an output band of an PLL in response to an output frequency from the PLL, both a conversion function setting parameter for a variable divider in the PLL and a dividing number setting parameter for a variable divider in the reference oscillator are adjusted so that the output frequency and the selected frequency setting parameter are satisfied.

Frequency synthesizer which suppresses a spurious

The detector comprises a first distributor for distributing a signal wave, a 45 degree shifter for shifting a local oscillation, a first even harmonic mixer and a second even harmonic mixer for generating a mixed wave between a double frequency wave of said local oscillation wave and said signal wave. The present invention can be used for increasing the accuracy and downsizing of quadrature mixer used in a receiving transmitting apparatus of a wireless communication system.

Detector and receiving and transmitting apparatus

A frequency synthesizer, including a direct digital synthesizer (DDS) for providing wave amplitude data as a standard signal source, and a phase lock loop for comparing a branched synthesizer frequency with the standard signal source at a phase comparator. A frequency converter converts the output frequency of the DDS to a higher frequency and provides the resultant higher frequency to the phase comparator in the phase loop. A small loop dividing ratio is obtained by converting the low frequency of the DDS to a higher frequency. A spurious of the synthesizer output signal is reduced and provides a low power consumption apparatus.

Frequency synthesizer

Growing community of inventors

Tokyo, Japan

Akio Iida