The application provides a communication
signal automatic modulation recognition method based on symplectic geometry
modal decomposition, belongs to the field of
signal automatic modulation recognition, and carries out
phase space reconstruction on a preprocessed modulation
signal, obtains a trajectory matrix and constructs a
covariance matrix, decomposes the
covariance matrix, obtains an eigenvector matrix and an eigenvalue, constructs and converts a reconstruction matrix, and obtains a dynamic
modal component; the dynamic
modal component with an eigenvalue greater than a set value is taken as a main modal, the dynamic modal component with an eigenvalue less than the set value is superimposed to form a residual signal, a multi-channel
time domain modal
feature matrix is constructed, and a spectrum diagram is generated; the multi-channel
time domain modal
feature matrix and the spectrum diagram are input into a trained SGFN model, the multi-channel
time domain modal
feature matrix enters a time domain
branch, the spectrum diagram enters a
frequency domain branch, a time domain eigenvector and a
frequency domain eigenvector are weightedly fused, classification is carried out, and a modulation type is obtained; and a
system is also provided; and the modulation recognition accuracy under low signal-to-
noise ratio and
small sample conditions is improved.