Temperature strain monitoring system and method based on different doped dual-core weak reflection FBG array

The invention discloses a temperature strain monitoring system and method based on a different doped dual-core weak reflection FBG array. The system comprises a broadband pulse light source, a plurality of optical fiber couplers, a reflector, an optical switch, a dual-core optical fiber fan-out device, a dual-path photoelectric detector, an optical fiber delay line, a signal processing unit, a computer, a dual-core weak FBG array and an optical fiber. Dual-fiber-core time division multiplexing and the OFDR technology are combined, different doped fiber cores are used for alternately achieving in-situ monitoring of the same test point in the time domain, different temperature/strain sensitivity coefficients are achieved, signal decoupling is achieved through the pulse light source of the same wavelength, the advantage that a weak grating can achieve distributed large-capacity monitoring is kept, the OFDR monitoring technology based on wide pulse laser signals can be realized, two indexes of spatial resolution