Abstract: A waveguide modulation circuit branches a first short circuit from a main waveguide and branches a second short circuit from the first short circuit. The second short circuit is branched by an H-plane slit coupling at a position distant from the short-terminal of the first short circuit by a length of a half wavelength or some multiples thereof and this second short circuit is short-circuited or conductively terminated at a length of a half wavelength or some muliples thereof distant from its branch point. In the second short circuit, a switching diode is loaded at a predetermined position distant from the short-terminal towards the branch point. A pulse train of the modulation signal is appled to this diode to attain a 2-phase PSK-modulation circuit. A wave absorber may be attached to the short-terminal of the first short circuit, whenever necessary. A 4-phase PSK signal can also be obtained.

Abstract: A remote control system for a mobile object, comprising radio beacons each consisting of a master station and some substations, a mobile communication station mounted on each auto-pilot mobile for receiving the radio wave, such as millimetric, from each radio beacon, to let the mobile recognize its own position on the route map, and a control station for transmitting and receiving signals by radio waves to and from the mobile station so as to instruct and correct the moving route of the mobile. Each mobile station is equipped for detecting any corrugations on the route immediately ahead of it, for detecting the ground speed of the mobile, and preferably, for detecting the direction of the mobile so that each mobile station can manage the speed of the mobile object as its master, and can correct and change the route of the mobile on the map by the discriminated signals from these detectors, and the instructions from the control station on the basis of discrimination signals.