Optical signal modulation format recognition method and system based on nonlinear digital processing

Abstract

The invention relates to an optical signal modulation format recognition method and system based on nonlinear digital processing in the field of optical fiber communications. The system comprises a TDC, an OA, an optical filter, a high-speed optical detector, a low-speed asynchronous sampler, an analog-digital converter and a main control module. The main control module drives the TDC to generate a series of chromatic dispersion values, N sampling digital signals p1, p2, ... and pN are recorded under each chromatic dispersion value, and an output signal <Pout> is calculated according to the formula that <Pout>=1 / N *Sigma Nj=1(kpj)<n>, wherein n is the order and k is the adjusting coefficient; the <Pout> values obtained under the chromatic dispersion values are stored to be feature value arrays in order of the chromatic dispersion values, the feature value arrays are matched with feature value array samples of signals of the known modulation format, and therefore the modulation formats of input optical signals are judged. The method and system are applicable to signals of various modulation formats and rates, the working waveband is wide, greater tolerance is achieved for signal transmission chromatic dispersion and OSNR degradation, and the requirement for the rates of sampling and the analog-digital converter is low. The method and system have the advantages of being simple in structure, high in cost performance and wide in application range.

Description

technical field [0001] The invention relates to the technical fields of optical fiber communication, signal identification and digital signal processing, in particular to a method and system for identifying an optical signal modulation format. Background technique [0002] The ultimate goal of communication is to achieve fast, effective, safe and accurate transmission of information. Due to the limitation of channel capacity, communication signals need to adopt different modulation methods to meet different needs of users. With the rapid development of modern communication technology, the modulation methods in the communication system tend to be diversified and complicated. The identification of the modulation mode of the communication signal is an important part of the field of interception signal processing. It needs to determine the modulation mode of the received signal and extract the corresponding modulation mode under the condition of complex environment and noise in...

AI Technical Summary

Problems solved by technology

[0010] The technical problem to be solved by the present invention is to propose an optical signal modulation format identification method and system based on digital nonlinear processing, which overcomes the narrow working band existing in the prior art, small tolerance to signal transmission dispersion and OSNR degradation, and device volume Large, high power consumption and other defects

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