The invention provides an
optical fiber backscattering measurement method and device based on the
spread spectrum technology. The method comprises the steps that a sending sequence carries out
phase modulation on
light source signals through DPSK modulation; DPSK optical signals generated after
phase modulation enter an
optical path to be measured; DPSK optical signals reflected or backscattered from the
optical path to be measured enter a
delay interferometer through a first optical directional coupler or an
optical circulator, so that
demodulation of the DPSK optical signals is achieved; photovoltaic conversion is carried out on the demodulated DPSK optical signals; related despreading is carried out on signals generated after photovoltaic conversion through the
local sequence so that optical backscattering measurement can be carried out. According to the
optical fiber backscattering measurement method and device based on the
spread spectrum technology, by combining the DPSK modulation technology with the
spread spectrum technology, the bipolarity of optical domain spreading codes is achieved, the accuracy of
optical fiber backscattering measurement is improved, and the
dynamic range of optical
fiber backscattering measurement is expanded; by modulating the phase of the
delay interferometer, code element multiplication in related despreading is achieved, and the electronic
bottleneck in electric domain related despreading is overcome.