Four-channel down-channel filter applied to coarse wavelength division multiplexing system

Abstract

The invention relates to a four-channel down-channel filter applied to a coarse wavelength division multiplexing system. The filter is a two-dimensional photonic crystal with a triangular lattice dielectric column structure, and is realized by introducing Y waveguides with two arms having different parameters and terminal ends not forming passages and two resonant cavities with two hexagonal double-ring structures into two horizontal through waveguides. A dielectric column material of the whole structure is a phase change material, by inducing inner ring dielectric columns of the two resonantcavities to different phase changes from outside and selecting the radius of the dielectric columns at special positions appropriately, the four-channel down-channel filtering function meeting the requirements of the coarse wavelength division multiplexing optical communication system can be realized, so that the filter has excellent down-channel filtering characteristics. The four-channel down-channel filter is realized based on the structure of the two resonant cavities, and has the outstanding characteristics of simple structure, small size, easy realization and integration, high flexibility, and the size and interval of down-channel output wavelengths meet the requirements of the CWDM optical communication system currently in practical application, and has an important application in future optical integration system.

Description

technical field [0001] The invention is a multi-channel channel drop filter, which is mainly used in a coarse wavelength division multiplexing communication system to realize the selective drop of specific wavelength signals. Background technique [0002] As people enter the era of optical integration and all-optical communication, wavelength division multiplexing (WDM) systems have been extensively studied. The channel drop filter based on two-dimensional photonic crystal has the advantages of small size and easy integration, and has been more and more used in wavelength division multiplexing systems. The ring cavity structure has good spectrum selection characteristics. The introduction of a waveguide and ring resonator structure into a two-dimensional photonic crystal can realize a high-performance channel drop filter. In recent years, many researchers have designed resonant cavities with different structures to realize the forward or backward output function of signals;...

AI Technical Summary

Problems solved by technology

This structure also has the outstanding problem that four resonant cavities are required to realize the four-channel drop output, which greatly increases the complexity, size and cost of the device structure, and the size and spacing of the four drop wavelengths do not meet the requirements of the CDWM system or DWDM. System Specific Requirements

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