Single-carrier optical communication signal detection method and device

Abstract

The invention discloses a single-carrier optical communication signal detection method and a single-carrier optical communication signal detection device. A first optical branching module divides an optical signal into a receiving signal L1 and a receiving signal L2; a time delay module performs time delay processing on the L1 to obtain a time delay optical signal; a second optical branching module divides the time-delay optical signal into a time-delay optical signal M1 and a time-delay optical signal M2; the direct detection module directly detects the M1 to obtain an electric signal R1; thedifferential detection module performs differential detection on the L2 and the M2 to obtain an integral electric signal R2; the first calculation module performs subtraction on the electric signal R1 and the electric signal R2 to obtain a detection electric signal R3; the conversion module preprocesses the detection electric signal R3 and performs analog-to-digital conversion to obtain a digitalelectric signal R; the digital signal circuit module processes the R through a digital signal circuit and then outputs a sending end digital baseband signal. According to the invention, the problem of low sensitivity caused by SSBI interference in the existing direct detection is solved, and the complex-valued signal direct detection device with higher transmission sensitivity and higher spectrumutilization rate is obtained under the conditions of low complexity and low cost.

Description

technical field [0001] The invention relates to the field of signal detection and processing of an optical communication direct detection receiver, in particular to a single-carrier optical communication signal detection method and a device thereof. Background technique [0002] In the prior art, two methods of coherent detection and non-coherent detection are generally used for receiving optical communication signals. Coherent detection can detect the amplitude and phase of the modulated signal, that is, coherent detection can realize the recovery of field signals. Therefore, in a coherent detection system, the transmitting signal usually adopts Inphase Quadrature (IQ) modulation, which can increase the spectral efficiency (Spectral Efficiency, SE) of the transmitted signal; in addition, the recovery of the field signal makes the received signal The phase-related damage in the channel can be compensated by means of digital signal processing, such as chromatic dispersion (C...

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Problems solved by technology

[0007]1. The receiver uses a local oscillator laser to achieve coherent detection with high cost, complicated frequency offset control and high power consumption;

[0008]2. The receiver adopts the traditional direct detection method, which cannot detect the field signal, but can only receive the intensity modulation signal;

[0009]3. There is SSBI interference noise in the self-coherent receiving mode of the receiver, which reduces the sensitivity of the receiver;

[0010]4. The receiver adopts carrier insertion plus frequency guard interval receiving mode, and the spectrum efficiency is low;

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