| 摘要 |
PURPOSE:To accurately and easily detect the position of a mobile body by storing position information sent from a fixed radio equipment to a transponding card fitted to the mobile body and sending the position information included in a reply signal from the transponding card to the fixed radio equipment. CONSTITUTION:A polling signal POL and address signals AD1, AD2 representing the position of each fixed radio equipment are sent from fixed radio equipments TRX11, 12. In this case, transmission signals from each radio equipment TRX are sent entirely in the same timing. Thus, plural polling signals and address signals, that is, any of POL+AD1 and POL+AD2 reaches a TRC15, but since the signal POL+AD1 having a stronger radio wave masks the signal POL+AD2 having a weak radio wave, only the address AD1 is stored in the TRC15. Further, the TRC15 sends an ID signal and a position signal ID+AD1 as a reply signal. The signal is received by each fixed radio equipment. |
