| 摘要 |
PURPOSE:To dispense with a dummy guiding radio line, to omit work for encoding the dummy guiding ratio line and to also dispense with the movement of an antenna, by a method wherein an airborne station and a ground station are provided and a change-over circuit is changed over on the basis of a condition data in a dummy state by a change-over control apparatus so as to receive in the entirely same way as such a case that a moving body actually runs along an encoded guiding radio line. CONSTITUTION:When positional detection is performed on the ground, the output of the transmission apparatus 12a of an airborne station is emitted through an antenna 13 while loop coils 141-14n piled up in the numbers equal to the logarithm of encoded induction radio lines are provided at a position electromagnetically connecting to the antenna 13 on the ground and connected to the position detecting apparatus 16a of a ground station by lead wire pairs l1-ln. Change-over circuits 171-17n such as relays or analogue switches for changing over the phases or receiving intensities of the transmission waves received by the loop coils are interposed to the intermediate parts of the lead wire pairs. The changing-over of the phase can be realized by reversing the contact lines of the lead wire pairs while the changing-over of receiving intensites can be realized by short-circuiting/opening the lead wire pairs or changing over the connection of an attenuator. |
