Désentrelacement de clics par analyse du rythme

National audienceTous les odontocètes émettent de courtes impulsions acoustiques (clics) pour satisfaire une activité de localisation, de chasse ou de communication. Ces impulsions sont le plus souvent émises en trains rythmés. Il est très fréquent d'enregistrer simultanément les clics de plusieurs animaux. Cet article présente une méthode permettant de séparer les trains de clics enregistrés sur un unique hydrophone afin de connaître le nombre d'animaux ayant émis simultanément. La méthode proposée est testée avec succès sur des données simulées et sur des données réelles

De-interleaving of Radar Pulses for EW Receivers with an ELINT Application

De-interleaving is a critical function in Electronic Warfare (EW) that has not received much attention in the literature regarding on-line Electronic Intelligence (ELINT) application. In ELINT, on-line analysis is important in order to allow for efficient data collection and for support of operational decisions. This dissertation proposed a de-interleaving solution for use with ELINT/Electronic-Support-Measures (ESM) receivers for purposes of ELINT with on-line application. The proposed solution does not require complex integration with existing EW systems or modifications to their sub-systems. Before proposing the solution, on-line de-interleaving algorithms were surveyed. Density-based spatial clustering of applications with noise (DBSCAN) is a clustering algorithm that has not been used before in de-interleaving; in this dissertation, it has proved to be effective. DBSCAN was thus selected as a component of the proposed de-interleaving solution due to its advantages over other surveyed algorithms. The proposed solution relies primarily on the parameters of Angle of Arrival (AOA), Radio Frequency (RF), and Time of Arrival (TOA). The time parameter was utilized in resolving RF agility. The solution is a system that is composed of different building blocks. The solution handles complex radar environments that include agility in RF, Pulse Width (PW), and Pulse Repetition Interval (PRI)