The invention discloses an urban tunnel limit invasion prevention intelligent early warning method based on
distributed acoustic sensing, and relates to the field of underground monitoring and rail safety early warning, and the method specifically comprises the steps: inputting a data
record of a distributed
optical fiber; the records are subjected to standard size windowing,
spectral amplitude solving, range intercepting,
data truncation and normalization; training a convolutional auto-
encoder to reconstruct data, and performing encoding dimension reduction on the data by using an
encoder part; training a
random forest classifier by using the feature vectors subjected to real-
time data preprocessing and dimension reduction;
continuous data is preprocessed, and after dimension reduction of the data by a
convolution encoder, detection and classification are carried out by using a
random forest; and performing post-
processing based on
signal space-time continuity screening on a detection result to obtain an accurate detection and
classification result. According to the invention, the construction signals in the
distributed acoustic sensing data are monitored in real time by using the
convolution auto-encoder and the
random forest algorithm, detection and accurate classification are carried out with high temporal-spatial resolution, and intelligent early warning of track construction based on distributed optical fibers is realized.