108results about How to "Long sensing distance" patented technology

A combined type distributed optical fiber sensing system integrated with chaotic light source and coherent detection is disclosed and comprises a laser module, a polarization control module, a first optical switch, a first coupler, a pulse modulation and polarization scrambling module, a second coupler, a feedback device, a third coupler, a second optical switch, an EDFA light amplifier, a circulator, an optical fiber, a third optical switch, a fourth coupler, a fourth optical switch, a fifth optical switch, a balance photoelectric detector, a data collecting module, a data analyzing and processing module and a display device, wherein a coherent light time domain reflectometer or a chaotic light time domain reflectometer is chosen to be used in the system according to monitoring needs; by switching optical switch combinations, the coherent light time domain reflectometer or the chaotic light time domain reflectometer can be obtained. The beneficial effects of the combined type distributed optical fiber sensing method and system are that most of measuring devices in the system are employed by two measuring solution, the utilization efficiency of the sensing devices is improved, and system links are jointly monitored by the two measuring solutions; the detection sensitivity, the sensing distance and the positioning precision of the system can be optimized.