Optical Signal Modulation Format Recognition Method Based on Spectral Features

Abstract

The invention relates to a modulation format identification method and system based on signal spectral characteristics. The system comprises an optical amplifier (OA), an optical spectrum apparatus (OSA) and a data signal processing (DSP) system. First, an optical signal to be identified enters the OA and is amplified to have certain power, then injected to the OSA; center frequency estimation of the optical spectrum output from the OSA is carried out; using the center frequency as a reference, optical signal spectrums having a frequency range of + / -100GHz are intercepted; a characteristic vector of the optical sample is abstracted through a principal component analysis (PCA) algorithm module; the characteristic vector is input in an algorithm identification module of a pre-trained support vector machine (SVM) to determine the modulation formats and speed of the optical signal under test. The provided method requires no prior information to work and is suitable for switch modulation and advanced modulation format signals; no high speed detector is required; the method has large signal transmission damage tolerance, simple structure and wide application range.

Description

technical field [0001] The invention relates to the technical fields of optical fiber communication, modulation and demodulation of optical signals and digital signal processing. Background technique [0002] With the development of optical communication technology, there are more and more optical signals with different rates and modulation formats in the optical communication network to meet the requirements of different data transmission services. The most commonly used formats include on-off keying (OOK), optical duobinary (ODB), binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), and hexadecimal quadrature amplitude modulation (16QAM). light signal. On the other hand, the commonly used rates of optical signals include 2.5Gbps, 10Gbps, 40Gbps and 100Gbps and so on. Optical signals with different modulation formats have different advantages and are suitable for different scenarios. Generally speaking, low-level modulation formats are suitable for sce...

AI Technical Summary

Problems solved by technology

The advantage of this method is that there is no limit to the signal rate and the system structure is simple. The disadvantages are that the device is bulky, the power consumption is high, and the working band is limited.

The identification method based on digital coherent optical receiver is to obtain the signal amplitude and phase information by extracting the I / Q component of the signal, and then obtain the signal constellation diagram to identify the optical signal. This method has a wide range of applications and has strong anti-CD and PMD The ability to damage, but the system structure is complex, the cost is extremely high, and it depends on high-speed photoelectric conversion devices, and there is a problem of speed limitation

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