Abstract: 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 shifters 9a and 9b and variable attenuators 19a and 19b, and variable phase shifters 10a and 10b and variable attenuators 20a and 20b are 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 attenuator 21 inserted independently from the variable attenuators 19a and 19b, and therefore, radome correction and EIRP control can be simultaneously realized by a relatively simple circuit.

Abstract: In a variable power divider including a first 90° phase combiner (30), a second 90° phase combiner (40), and a phase-amplitude adjustment block (50), the phase-amplitude adjustment block (50) includes, correspondingly to two-channel polarized signals, variable phase shifters (51, 52) for adjusting their phase amounts and variable attenuators (55, 56) 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 (60). Further, there are included a phase shifter (53) and an attenuator (57) provided on two-channel signal lines between an orthomode transducer (20) and a first 90° phase combiner (30) and for equalizing the amplitudes and phases of the two-channel polarized signals.

Abstract: An antenna apparatus in which a combination of rectangular waveguides 9a and 10a and a combination of rectangular waveguides 9b and 10b are disposed bilateral symmetrically to each other, and a waveguide orthomode transducer 13 is disposed above a waveguide orthomode transducer 8 is 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.

Abstract: In a variable power divider including a first 90° phase combiner (30), a second 90° phase combiner (40), and a phase-amplitude adjustment block (50), the phase-amplitude adjustment block (50) includes, correspondingly to two-channel polarized signals, variable phase shifters (51, 52) for adjusting their phase amounts and variable attenuators (55, 56) 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 (60). Further, there are included a phase shifter (53) and an attenuator (57) provided on two-channel signal lines between an orthomode transducer (20) and a first 90° phase combiner (30) and for equalizing the amplitudes and phases of the two-channel polarized signals.

Abstract: 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 shifters 9a and 9b and variable attenuators 19a and 19b, and variable phase shifters 10a and 10b and variable attenuators 20a and 20b are 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 attenuator 21 inserted independently from the variable attenuators 19a and 19b, and therefore, radome correction and EIRP control can be simultaneously realized by a relatively simple circuit.

Abstract: An antenna apparatus in which a combination of rectangular waveguides 9a and 10a and a combination of rectangular waveguides 9b and 10b are disposed bilateral symmetrically to each other, and a waveguide orthomode transducer 13 is disposed above a waveguide orthomode transducer 8 is 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.