Short-distance optical fiber transmission system and signal detection and fault positioning method thereof

The invention discloses a short-distance optical fiber transmission system and a signal detection and fault positioning method thereof, and the method comprises the steps that a laser is controlled to emit light pulses through a pulse controller, and the light power emitted by the laser is detected through a light power detection module; after the optical pulse passes through the optical fiber transmission network, an optical signal is reflected back to the optical coupler, the reflected optical signal is detected through the photoelectric detector, and reflected light power is obtained after calculation processing; optical signal echo time is calculated, and a fault point distance L is calculated by combining the refractive index of light to be measured; the optical power emitted by the laser and the reflected light power are combined to calculate an optical fiber signal attenuation coefficient, and a fault point is positioned at the same time. The optical fiber fault point distance, the optical power attenu