Mitsubishi Denki Kabushiki Kaisha

Izuru Naitou

Norio Takeuchi

Yutaka Shimawaki

Tomohiro Mizuno

Yoshihiko Konishi

Eiichi Sakai

Hiroaki Miyashita

Hiroyuki Satou

Soichi Matsumoto

Kazushi Nishizawa

Hidenori Yoshizawa

Yoshihiko Imai

Nobuyasu Takemura

A variable power distributor capable of calculating an error between transmission lines of two systems after building a variable power distributor and correcting the set value of the amplitude and the phase according to the error, an error detection method for the variable power distributor, and a set value correction method is provided. The variable power distributor includes: a two-way distributor provided on an input side of a set of transmission lines consisting of a first and a second transmission line; a 90-degree hybrid circuit provided on an output side of the set of transmission lines; and a variable phase shifter, variable resistance attenuator, and a power amplifier provided on each line of the set of transmission lines between the two-way distributor and the 90-degree hybrid circuit. The variable power distributor further includes an error detection unit that monitors an output signal from the 90-degree hybrid circuit and detects an error existing in each component between the first and the second transmission lines based on the monitor output.

Variable power distributor, error detection method thereof, and set value correction method

In a moving body satellite communication apparatus for performing communication with a satellite by an antenna with a radome mounted on a moving body such as an aircraft, loss due to transmission through the radome, and distortion of polarization characteristics are compensated in the inside of the antenna. Variable phase shiftersandand variable attenuatorsand, and variable phase shiftersandand variable attenuatorsandare respectively controlled as one body in each channel, and the whole power EIRP radiated from the antenna is also optimally controlled by a common variable attenuatorinserted independently from the variable attenuatorsand, and therefore, radome correction and EIRP control can be simultaneously realized by a relatively simple circuit.

Mobile satellite communication system

In a variable power divider including a first 90&#xb0; phase combiner (), a second 90&#xb0; phase combiner (), and a phase-amplitude adjustment block (), the phase-amplitude adjustment block () includes, correspondingly to two-channel polarized signals, variable phase shifters () for adjusting their phase amounts and variable attenuators () for adjusting amplitudes (attenuation amounts), and the phase amounts and the amplitudes of the two-channel polarized signals can be adjusted by an antenna control unit (). Further, there are included a phase shifter () and an attenuator () provided on two-channel signal lines between an orthomode transducer () and a first 90&#xb0; phase combiner () and for equalizing the amplitudes and phases of the two-channel polarized signals. By this, an antenna apparatus can be inexpensively provided which uses a reflector antenna () to perform transmission/reception of a signal to/from a satellite at high accuracy, and is miniaturized to be suitable for mounting on an aircraft or the like.

Antenna unit

A multibeam antenna apparatus is disclosed. The multibeam antenna apparatus includes a main reflector ( ), a sub-reflector ( ), a focused beam feeder ( ), a primary radiator array ( ) having a plurality of primary radiators ( ), and a lens array ( ) having a plurality of wavefront transformation lenses ( ) corresponding to the plurality of primary radiators ( ), respectively. The lens array ( ) can be placed in the vicinity of a front end of the primary radiator array ( ). As an alternative, the lens array ( ) is placed in an electric wave propagation range of the focused beam feeder ( ) where multiple beams which constitute a multibeam are spatially isolated from one another in terms of electric power. Thus the multibeam antenna apparatus can prevent an error from occurring in the orientation of each beam.

Multibeam antenna apparatus

Growing community of inventors

Tokyo, Japan

Izuru Naitou