POSITION DETECTION DEVICE FOR MOBILE OBJECT

摘要

PURPOSE:To provide a device at low cost and with high reliability by connecting the both sides of an open transmission line to a receiver through respectively different transmission lines and transmitting a high frequency signal from a transmitter for a mobile object, thus detecting a difference in frequencies under a constitution incorporating the above design. CONSTITUTION:An open-type transmission line 21 is laid in parallel along a channel for a mobile object 22 and the both sides O1, O2 of the said line are connected to one unit of receiver 25 at O3. A transmitter 24 and an antenna 23 are mounted at the mobile object 22 and the antenna 23 and the open-type transmission line 21 are electromagnetically connected together. A high frequency signal transmitted from the antenna 23 is propagated toward the both ends of the open-type transmission line 21 and a received signal from the both ends of the transmission line 21 is compared by means of the receiver 25. The propagation time between the individual ends of the transmission line 21 and the receiver 25 is fixed regardless of the position of the mobile object 22. If this value is corrected, the position of the mobile object 22 can be detected on the ground through comparison of frequency differences when a high frequency signal is a frquency sweep signal. Under this constitution, it is possible to provide the device at low cost and with high precision.