Two dimensional coherent optical code division multiple access (OCDMA) coder and decoder based on coupling cascaded microring array

Abstract

The invention discloses a two dimensional coherent optical code division multiple access (OCDMA) coder and decoder based on a coupling cascaded microring array. The coder comprises two optical waveguides and N groups of microring array. Each group of microring array is formed by cascading a plurality of microrings. The upper and lower microrings of each group of microring array are respectively coupled with the two waveguides. Every two adjacent microrings in the middle are coupled with each other. An optical signal comprising different wavelengths is input from the input end of one waveguide, lights meeting resonance conditions pass through N groups of microring array, the position sequence of which is in forward direction arrangement, and then is output from the download end of the other waveguide, so that the wavelength selection is completed. Two dimensional coding of wavelength and phase is realized through attaching a specific phase to each reflection wavelength. In a receiving end, the position sequence of N groups of microring array is in reverse direction arrangement, and the phase shifter is arranged for changing inverse phase. Compared with the prior art, the two dimensional coherent OCDMA coder and decoder have low cost, small volume, high quality factor, low loss, high integration level and simple technology, and resist multi-site interference, and the user capacity is easy to expand.

Description

technical field [0001] The invention belongs to the technical field of optical fiber communication, and in particular relates to a two-dimensional coherent optical code division multiple access codec based on a coupled series microring array. Background technique [0002] With the vigorous development of Internet services and the increasing demand for bandwidth, the high-capacity and high-speed optical fiber communication technology has attracted more and more researchers' attention. In order to further improve the utilization rate of optical fibers and tap larger bandwidth resources, various optical multiplexing methods have been proposed, mainly including wavelength division multiplexing (WDM), optical time division multiplexing (OTDM) and optical code division multiple access (OCDMA). . Among them, OCDMA technology has become a hot spot in the field of optical communication coding due to its unique advantages such as strong confidentiality, anti-interference, anti-multip...

AI Technical Summary

Problems solved by technology

However, in this encoding and decoding scheme, an optical fiber delayer is required for each wavelength, which is not easy to integrate; and the use of AWG introduces a large loss and high cost

[0009] Although the above patents can realize the encoding and decoding of the OCDMA system, they have limitations in terms of anti-multiple access interference, manufacturing process, integration degree, and the number of users that can be accommodated.

For example, the optical fiber delay line coded OCDMA system needs more components and is relatively heavy. In actual production, it is necessary to accurately control the delay length of each delay line, and the loss is relatively large; The volume is huge, and the fiber gratings that make up the array must be matched consistently during production, and the precision requirements are very high, and there is inevitably multiple access interference between user spreading sequences

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