TF-QKD SYSTEM AND METHOD

Disclosed in the present invention are a TF-QKD system and a stable TF-QKD implementation method. The frequency-locked reference light and the phase reference light are subjected to polarization-maintaining wavelength division coupling into a reference optical signal at the Charlie end, so that in the Alice end and the Bob end, two polarization-maintaining wavelength division multiplexers are used in combination with the frequency locking technology to realize polarization-consistent wavelength division coupling of a quantum optical signal and the phase reference light, and an EPC or manual intervention is not needed, so as to ensure the stability of polarization-consistent coupling using a simple optical path. In addition, polarization compensation can be firstly performed on the reference optical signal in the Alice end and the Bob end, so that the stability of the frequency-locked reference light and the phase reference light is also ensured is ensured by a polarization-consistent coupling module in the present application, thereby ensuring the stability of the frequency locking effect.