The invention provides an adaptive
radiation source modulation identification method based on time-
frequency analysis. The method comprises the steps of I, carrying out time-
frequency analysis on a received
radiation source
signal by
use of time frequency distribution, converting the
radiation signal from a time-domain
signal to a time-frequency two-dimensional image; II, reducing
computation complexity and characteristic dimension by use of an
image processing technology, and improving the proportion of
signal characteristic information in the image through normalization, binaryzation, image
thinning and image preprocessing operations; III, carrying out image shape characteristic extraction on the preprocessed image in combination with a second-order and four-order moment
estimation method by use of an adaptive
principal component analysis algorithm; and IV, identifying a modulation mode of the radiation source signal by use of an LIBSVM (
Library for
Support Vector Machine) classifier. According to the adaptive radiation source modulation identification method based on time-
frequency analysis, the characteristic missing of a low
signal to noise ratio signal can be effectively avoided, and characteristic redundancy of a high low
signal to noise ratio can be also avoided, and the modulation
identification rate is not affected at the same time.