| 摘要 |
PURPOSE:To reduce influence of a reflected wave in the radio wave propagation, and to measure a range exactly, by detecting a timing position of a pulse having a specific shape, among received response pulses. CONSTITUTION:In the transponder side, a radio wave received by an antenna 16 is led to a pre-selector 17, in which its receiving band is selected and its frequency is converted, the received waveform is linearly detected by a detecting part 19, and also a pulse timing of the first pulse of the received wave is decided by delay comparing part 20. Subsequently, in accordance with this timing, timing of a resending pulse delayed by a constant interval of time is made in a control part 22, is sent to a transmitting system 21, and a resending pulse is generated. A receiving timing of the first pulse is derived by receiving this reradiated signal by a receiving system. After that, it is compared with a sending timing by a time control part, by which a range is measured. |
