Digital signal processing is used in the interception of digital communication signals. Due to the inherent security features, frequency hopped signals (FH) are widely used in both military and commercial communication applications. The interception of FH signals can be addressed in several ways. In this work we use the Instantaneous Correlation Function (ICF) to represent non-stationary signals. We relate the wavelet transform the ICF surface of a signal to its Wigner-Ville Distribution (WVD). The signals can be observed in the scale surfaces of the wavelet domain. An energy analysis is applied to the surfaces (in the wavelet domain) to identify the scale of the FH signal and to estimate the hop frequency. The FH signals can also bc idcntified by inspecting the pattern of the scales of a multiple-hop-observation interval. If all hop frequencies are within one wavelet scale, then the FH signal can be identified by a set of distinct hop frequencies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.