Method and device for reconstructing a backscattered electromagnetic vector wave

A method for reconstructing an electromagnetic vector wave backscattered in all or part of an optical fiber, said method comprising:

• A step of injecting into the optical fiber a light signal of a frequency v0 or v0+vA,
• A step of polarization-resolved heterodyne optical detection including generation, by an optical separation means and from a backscatter of the injected light signal and an electromagnetic wave from a local oscillator, of at least two orthogonally polarized backscattered light signals, producing a beat preferably of a frequency vA,
• A step of converting, by at least two photodetectors, the orthogonally polarized backscattered light signals into initial analog signals,
• A step of electrical homodyne detection, by an IQ demodulator, for IQ demodulating each of the initial analog signals, so as to generate I (I1, I2) and Q (Q1, Q2) demodulated analog signals for each of the orthogonally polarized backscattered light signals, and
• A step of reconstructing, by a processing module, the electromagnetic vector wave backscattered in all or part of the optical fiber from the I (I1, I2) and Q (Q1, Q2) demodulated analog signals generated.