Digital modulation signal identification method under pulse noise

Abstract

The invention discloses a digital modulation signal identification method under pulse noise. The method comprises the following steps that the fractional low-order fuzzy function of digital modulation signals is calculated; the tangent plane of zero Doppler frequency shift of the fractional low-order fuzzy function is intercepted, and the tangent plane is converted into a two-dimensional image and fills below the edge of the image so as to become a color image with color; graying, binarization, image segmentation and image size normalization are performed on the color image and translation and scale normalization are performed on the image; and the Zernike moment of the image is extracted to act as the characteristic vector of identification, and the digital modulation signals are identified by using a probability neural network classifier. The digital modulation signal identification method has great identification performance on the digital modulation signals 2ASK, 4ASK, 2FSK, 4FSK and BPSK under standard distribution pulse noise.

Description

technical field [0001] The invention belongs to the technical field of communications, and in particular relates to a method for identifying digital modulation signals under impulse noise. Background technique [0002] Signal modulation identification is a key technology between signal detection and demodulation, and it is widely used in military and civilian fields. Traditional digital modulation signal identification methods mostly use Gaussian noise as the noise model, but the noise in the actual environment often has the property of spikes and the probability density function of the noise has a thick tail. The research of Prof. Nikias and others proves that Alpha stable distribution is an effective model to describe this kind of impulse noise signal. Therefore, it is meaningful to study the identification method of digital modulation signal under impulse noise. [0003] Vinod AP et al. used the normalized fourth-order cumulant based on fractional low-order statistics t...

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Problems solved by technology

[0004] The purpose of the present invention is to provide a recognition method for digitally modulated signals under impulse noise, aiming at solving the problem of poor recognition performance when the mixed signal-to-noise ratio is low in existing recognition methods for digitally modulated signals under pulse noise, and the recognition There are few types of signals, and the recognition effect is not ideal

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