Optical fiber vibration detection method and device

Abstract

The invention discloses an optical fiber vibration detection method and device. The method includes the steps of unceasingly receiving N pulse echo data so as to obtain a frame of echo data, wherein distance units of the N pulse echo data are arrayed according to an N*M matrix; sequentially selecting the distance units from the Mth distance unit in the nth pulse echo data to serve as detection units H(i, j); selecting corresponding reference units according to the detection units H(i, j) so as to calculate a training detection threshold, a first-level constant false alarm rate detection threshold and a second-level constant false alarm rate detection threshold, comparing the training detection threshold, the first-level constant false alarm rate detection threshold and the second-level constant false alarm rate detection threshold with a training detection threshold, a first-level detection threshold and a second-level detection threshold respectively to obtain data exceeding the detection thresholds, repeatedly executing the steps k times to obtain the detection results of all the distance units in k frames of echo data, and then regulating a first-level detection threshold coefficient and a second-level detection threshold coefficient in a self-adaption mode according to the accumulated results of training detection to be used for next multi-frame detection. By means of the two-level CFAR detection method, the false alarm probability of the system is lowered, and the detection probability is improved.

Description

technical field [0001] The invention relates to the technical field of optical fiber vibration signal measurement, in particular to an optical fiber vibration detection method and device based on constant false alarm rate (CFAR) detection. Background technique [0002] With the development of the economy, oil and natural gas have become the most important energy sources for the development of the national economy. As the most ideal and economical transportation method for oil and natural gas, long-distance pipelines have been widely used. The oil and gas pipeline is the main artery of energy transportation. Once the pipeline leaks, it is easy to burn and explode, which not only affects the safe production of the pipeline, but also causes huge losses to the life and property of the country and the people. [0003] At present, the detection and alarm systems for oil and gas pipelines mainly include the following types: electronic pulse fence, microwave wall alarm, active infr...

AI Technical Summary

Problems solved by technology

However, the monitoring results obtained by this processing method have large errors and inaccurate alarms, which make long-distance complex vibration detection face severe challenges. It is urgent to carry out research on long-distance optical fiber vibration detection methods on this basis.

[0005] The main problem in existing research is that no suitable model has been established, especially no suitable signal detection model has been established, and the single-level alarm cannot take into account the performance of both false alarm and detection, so that the long-distance early warning system that has been put into production The efficiency is low or even put aside, the signal processing link in the optical fiber early warning system has become the main bottleneck of the system and industrial development

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