| 摘要 |
This application describes methods and apparatus for remotely indicating a location of interest in an area, for instance the location of an event in the area. The method comprises positioning an acoustic source at the location of interest,activating the acoustic source to produce a predetermined acoustic output and performing distributed acoustic sensing on at least one optical fibre deployed at least partly in the area. The acoustic source thus acts as an acoustic marker which can be remotely detected by the distributed acoustic sensor. The acoustic signals detected by the distributed acoustic sensor are therefore analysed to detect said predetermined acoustic output and determine the location of the acoustic source. The method is particularly applicable to transport networks already provided with optical fibre along the length of the network and can be used to indicate the location of work parties or emergencies. |
