| 摘要 |
<p>PURPOSE:To improve the noiseproof characteristic by detecting the PN codes transmitted from an on-ground transmission part and two on-vehicle transmission part, on an on-ground receiving part, as for the constitution in which a train is detected by laying an induction loop along a traveling passage, as for an urban type traffic engine which is not equipped with rails. CONSTITUTION:A train detecting device is equipped with an on-ground transmission part (a) which diffusion-processes a pair of transmission signals having a frequency difference by a prescribed PN code, and alternately supplies the signal to the starting end side of an induction loop P, keeping a prescribed interval. Further, the train detecting device is equipped with the first and the second on-vehicle transmission parts (c) and (d) which diffusion-process the signal by using the same PN codes to a pair of prescribed transmission signals and continuously send the signals from the longitudinal position in the advance direction of the train (a) to the induction loop P. An on-ground receiving part (b) is installed on the terminal side of the induction loop P, and the PN code is extracted by decoding-processing the received signal by a pair of transmission signals, and when the first PN code is extracted with a prescribed cycle or more, the intrusion of the train is judged, while, if the second PN code is extracted with a prescribed cycle or more, the start of the train is judged.</p> |
