Abstract: A planar antenna including slot arrays configured to set a narrow interval between elements so as to perform beam scanning in a wide angle range while keeping low loss and low profile. The planar antenna includes: a coaxial line including an inner conductor, an outer conductor provided so as to surround a circumference of the inner conductor, and both ends short-circuited; a feeding mechanism for exciting the coaxial line; and a plurality of slots formed on the outer conductor with a certain angle with respect to a tube direction of the coaxial line and having approximately a resonance length.

Abstract: A planar antenna including slot arrays configured to set a narrow interval between elements so as to perform beam scanning in a wide angle range while keeping low loss and low profile. The planar antenna includes: a coaxial line including an inner conductor, an outer conductor provided so as to surround a circumference of the inner conductor, and both ends short-circuited; a feeding mechanism for exciting the coaxial line; and a plurality of slots formed on the outer conductor with a certain angle with respect to a tube direction of the coaxial line and having approximately a resonance length.

Abstract: An engine control system correctly determines when a vehicle overturns and includes a vehicle inclination angle detector arranged to detect an inclination of a vehicle relative to a horizontal plane, a cumulative-duration-of-inclination detector arranged to detect a cumulative duration for which an inclination angle detected by the vehicle inclination angle detector is greater than a predetermined angle, a rider's operation detector arranged to detect whether or not a rider is operating the vehicle, and an engine cut off device arranged to stop an engine of the vehicle when it has been determined that the vehicle has overturned, based on an output of the cumulative-duration-of-inclination detector indicating the cumulative duration for which the inclination angle detected by the vehicle inclination angle detector is greater than the predetermined angle, and an output of the rider's operation detector indicating that the rider is operating the vehicle.

Abstract: An engine control system correctly determines when a vehicle overturns and includes a vehicle inclination angle detector arranged to detect an inclination of a vehicle relative to a horizontal plane, a cumulative-duration-of-inclination detector arranged to detect a cumulative duration for which an inclination angle detected by the vehicle inclination angle detector is greater than a predetermined angle, a rider's operation detector arranged to detect whether or not a rider is operating the vehicle, and an engine cut off device arranged to stop an engine of the vehicle when it has been determined that the vehicle has overturned, based on an output of the cumulative-duration-of-inclination detector indicating the cumulative duration for which the inclination angle detected by the vehicle inclination angle detector is greater than the predetermined angle, and an output of the rider's operation detector indicating that the rider is operating the vehicle.

Abstract: A nonreflective waveguide terminator includes a waveguide portion and an electromagnetic wave absorber. The portion has a rectangular opening in a plane perpendicular to a radio-wave propagation direction. The portion has one open end in the direction and the other end closed by a terminating metal internal wall. The portion has a radio-wave propagation space surrounded by first and second metal internal walls parallel to a radio-wave electric field, and third and fourth metal internal walls perpendicular to the field. The exterior shape of the absorber is a parallelepiped. The absorber has a rear-end surface positioned at a predetermined distance from the terminating wall and parallel to the terminating wall or is provided against the terminating wall. The surface of the absorber having the largest rectangular area is on the third or the fourth metal internal wall.

Abstract: High frequency packages have a plurality of apertures (notches) as antennas, and each of these apertures possesses a specific resonance frequency that may exist within the frequency bandwidth used in the high frequency packages in a high frequency band. Thus, the resonance frequency produced within the package is shifted outside the frequency bandwidth. A high frequency package is provided with a metal frame disposed on a metal bottom plate and having apertures for connecting with external terminals, dielectrics being disposed on the bottom metal plate, and on which a high frequency transmission line and a plurality of input and output terminals are formed, microwave circuitry being contained in the metal frame, and a metal lid, wherein the frequency of the aperture's resonance arising from electromagnetic field between the metal frame and the metal bottom plate, is shifted outside the frequency bandwidth by diminishing and optimizing the width of the aperture.

Abstract: High frequency packages have a plurality of apertures (notches) as antennas, and each of these apertures possesses a specific resonance frequency that may exist within the frequency bandwidth used in the high frequency packages in a high frequency band. Thus, the resonance frequency produced within the package is shifted outside the frequency bandwidth. A high frequency package is provided with a metal frame disposed on a metal bottom plate and having apertures for connecting with external terminals, dielectrics being disposed on the bottom metal plate, and on which a high frequency transmission line and a plurality of input and output terminals are formed, microwave circuitry being contained in the metal frame, and a metal lid, wherein the frequency of the aperture's resonance arising from electromagnetic field between the metal frame and the metal bottom plate, is shifted outside the frequency bandwidth by diminishing and optimizing the width of the aperture.

Abstract: A nonreflective waveguide terminator includes a waveguide portion and an electromagnetic wave absorber. The portion has a rectangular opening in a plane perpendicular to a radio-wave propagation direction. The portion has one open end in the direction and the other end closed by a terminating metal internal wall. The portion has a radio-wave propagation space surrounded by first and second metal internal walls parallel to a radio-wave electric field, and third and fourth metal internal walls perpendicular to the field. The exterior shape of the absorber is a parallelepiped. The absorber has a rear-end surface positioned at a predetermined distance from the terminating wall and parallel to the terminating wall or is provided against the terminating wall. The surface of the absorber having the largest rectangular area is on the third or the fourth metal internal wall.

Abstract: An optical signal is output from an optical semiconductor element according to a high frequency signal. The optical semiconductor element is surrounded by a metallic package having a package base, a package cover and a seal ring so as to separate the optical semiconductor element from the outside air. An electromagnetic wave absorptive element is arranged on an inner surface of the metallic package to attenuate the high frequency signal leaking into the cavity of the metallic package, and the electromagnetic wave absorptive element is covered with a seal element so as to hermetically seal the electromagnetic wave absorptive element from the cavity. The seal element allows the high frequency signal to be transmitted through the seal element. The high frequency signal leaking into the cavity is transmitted through the seal element and is converted into heat energy in the electromagnetic wave absorptive element.

Abstract: An air conditioning apparatus for heating and cooling a room, which has a four-way valve to reverse the flow of a refrigerant, thereby switching the operation mode, heating or cooling, and which has a bypass line for bypassing an inside heat-exchanger, a control valve for controlling the flow ratio of the refrigerant passing through the bypass line and the inside heat-exchanger, and a refrigerant-heating element disposed in a line between the control valve and the compressor, thereby, in the defrosting mode, melting the frost formed on endothermic fins without cooling the room and without a liquid return to the suction side of the compressor.