Coherent light direct detection method and device and optical communication system

Abstract

The invention relates to the technical field of optical communication, in particular to a coherent light direct detection method and device and an optical communication system. According to the coherent light direct detection method of the invention, modulated signals are separated, so that four paths of component light signals can be obtained; photoelectric conversion is carried out according tothe four paths of component optical signals to obtain electric signals corresponding to the four paths of component optical signals; and detection is carried out according to the electric signals corresponding to the four paths of component optical signals to obtain light intensity corresponding to the four paths of component optical signals, calculation is carried out according to the light intensity corresponding to the four paths of component optical signals to obtain Stokes parameters corresponding to modulated signals, and the Stokes parameters corresponding to the modulated signals describe the polarization state of the modulated signals. According to the invention, the polarization state of the modulated signal is detected by adopting a non-coherent method through high-integration design, so that the direct detection of a coherent communication system is realized, the polarization demodulation is satisfied, the complexity is reduced, and the cost is reduced.

Description

technical field [0001] The present invention relates to the technical field of optical communication, in particular to a coherent light direct detection method, device and optical communication system. Background technique [0002] The existing long-distance coherent optical communication system needs to use a local laser at the receiving end to detect the phase information of the light by coherently with the received signal. communication principle such as figure 1 As shown, use a polarization beam splitter (PBS) to separate the received signal into X signal (X direction) and Y signal (Y direction) polarization plane components, and then separate the X signal and Y signal polarization components with the local oscillator light source (Localoscillator) optical signal beats through a 90° hybrid mixer to realize coherent demodulation of dual polarization signals, thereby realizing coherent optical communication. This technical solution is relatively complicated, and many dev...

AI Technical Summary

Problems solved by technology

This technical solution is relatively complicated and requires a lot of equipment. It needs to use PBS, local oscillator light source, mixer and other components, and the cost is relatively high.

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