Method for self-coherence detection of optical carrier radio frequency link based on polarization multiplexing

Abstract

The invention discloses a method for self-coherence detection of an optical carrier radio frequency link based on polarization multiplexing. The invention relates to the technical field of optical communication and microwaves. The method is shown in the attached drawing, and comprises a laser source, a vector signal source, a polarization controller, a polarization beam splitter, a polarization multiplexing Mach-Zehnder modulator, a single-mode fiber, an erbium-doped fiber amplifier, a 90-degree optical coupler and a balance photoelectric detector. According to the method, two paths of different radio frequency electric signals are used for respectively carrying out intensity modulation and phase modulation on two optical carriers with orthogonal polarization states in a polarization multiplexing Mach-Zehnder modulator; frequency mixing is carried out through a 90-degree optical coupler; signal processing is performed on the electric signal output by the balance photoelectric detectorto recover an original electric signal; the polarization multiplexing mode is used for improving the utilization rate of spectrum and light source power; self-coherent detection is used at the receiving end; and a local oscillation light source and a complex phase noise elimination algorithm are avoided, so that the system cost is reduced, and the requirement for the line width of the laser is lowered.

Description

Technical field [0001] The present invention relates to the field of optical communication technology and the field of microwave technology, and in particular to the structural design of an optical carrier radio frequency link based on coherent detection. Background technique [0002] With the need of terminal users to further increase the speed of the access network, the optical radio frequency has become the most promising technology in the next generation access network. The use of the optical radio frequency link as the communication link between the base station and the central station has a series of advantages such as greatly increasing the user access rate, making the network structure more flexible, and providing a higher number of accessible users. [0003] The traditional optical radio frequency link adopts the intensity modulation-direct detection structure, which is also the most commonly used link structure in the current access network. However, the intensity modula...

AI Technical Summary

Problems solved by technology

However, the intensity modulation-direct detection method is limited by the nonlinearity of the intensity modulation process. This type of microwave optical link has poor linearity and cannot meet the sensitivity requirements of the uplink.

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