The invention relates to the technical field of
digital signal processing, in particular to an
intermediate frequency signal conversion
system based on S-band
frequency conversion processing, which comprises the following steps: S1, de-noising an original
signal, S2, dynamically adjusting local frequency characteristics of the
signal through a self-adaptive time-frequency window, S3, extracting time-frequency characteristics of different frequency bands through
wavelet packet transformation, and S4, carrying out
frequency conversion on the extracted time-frequency characteristics of different frequency bands. The
wavelet packet transformation decomposes a signal into a plurality of frequency bands through multi-stage
decomposition, S4, dynamically adjusting the resolution of a time-frequency graph through a
reconstruction algorithm, and optimizing the reconstruction precision of different frequency components, S5, carrying out signal
feature extraction on the processed signal time-frequency graph and a
wavelet packet coefficient, and extracting features related to an S
frequency band from the signal, and S6, carrying out
wavelet packet transformation on the features related to the S
frequency band. Potential representation of a signal is learned through a variational auto-
encoder, and a low-dimensional feature space is extracted. According to the method, the high-
frequency noise in the S-band signal can be efficiently removed, the recognition capability of the signal mode is improved, the S-band signal is processed in real time, and dynamic optimization is performed according to the signal characteristics.