A Linear Optimization and Power Periodic Fading Compensation Method Based on Sagnac Loop

Abstract

The invention discloses a linear optimization and power periodic fading compensation method based on Sagnac ring. The device is shown in Figure 1 of the accompanying drawing of the description, including a laser LD, a polarization modulator PolM, a single-mode fiber SMF, and a polarization controller. PC, Sagnac Ring, Erbium Doped Fiber Amplifier EDFA, Polarizer Polarizer and Photodetector PD. The RF signal is modulated onto the optical carrier by PolM, the odd and even order sidebands of the modulated signal in orthogonal polarization states are separated by the polarization controller and the polarization beam splitter PBS in the Sganac ring, and the phase modulator is used bidirectionally in the Sagnac ring PM makes one polarization state in the clockwise direction modulated by the LO signal, and by introducing an appropriate phase shift between the two orthogonal polarization directions of the down-converted signal, the power fading caused by dispersion can be compensated for after photoelectric conversion, and the third order can be eliminated. Intermodulation distortion, realizing linear optimization, the invention has simple and compact structure, flexible tuning, large working bandwidth and strong system reconfigurability.

Description

technical field [0001] The invention relates to the technical field of optical communication and microwave technology, and mainly relates to linear optimization and power periodic fading compensation of an analog photonic down-conversion link. Background technique [0002] Microwave photonics is a new discipline that combines microwave radio frequency technology and photonics technology. It completes electrical signal processing in the optical domain, including signal generation, transmission, frequency mixing, filtering, etc. Microwave photonic links have the advantages of large communication capacity, low transmission loss, small size, light weight and anti-electromagnetic interference, and have broad application prospects in satellite communication, radar, electronic warfare and cable television. Microwave photonic frequency conversion technology is widely used in various fields of modern society. Traditional microwave down-conversion technology faces electronic bottlenec...

AI Technical Summary

Problems solved by technology

However, fiber chromatic dispersion will cause different time delays for signals of different frequencies, that is to say, different frequency components in the PD received signal will show different phase shifts

At this time, the transmission performance of the link will be affected by the dispersion of the fiber, causing the power of the transmission signal to decline periodically with the frequency and transmission distance of the transmission signal, making it impossible for the receiving end to extract useful signals, which has a great impact on the communication quality

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