Application de la technique «Frequency-Hopped» à la localisation de sources par un réseau de capteurs
Localization of Sources with a Frequency-Hopped Signaling Sensor Array
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In this paper, we present a different approach to the problem of estimating the angle of arrivals (AOA's) of D targets in Frequency-Hopped signaling sensors array for active systems, with D smaller than the number of sensor elements, L . This method is based on the application of the Maximum Likelihood Estimator for a new proposed model of received data available in different channels . The simulation results show that this approach improves the resolution in the estimation of the angle of arrivals compared with Monotone-Frequency signaling case. Its drawback, however, is that when the Signal-to-Noise Ratio, SNR, is low the performance deteriorates and a large number of snapshots is required.
Résumé
Dans cet article, nous présentons une méthode pour la résolution du problème d'estimation des angles d'arrivée de D cibles , par un réseau de L capteurs, où D < L, pour les systèmes actifs émettant des signaux codés en «Frequency Hopped ». Cette méthode est basée sur l'application de l'estimateur du maximum de vraisemblance à un nouveau modèle de données reçues sur différents canaux. Les résultats de simulation montrent que cette approche améliore la résolution des angles d'arrivée des cibles, comparativement à celle de la fréquence monotone . Cependant, quand le rapport signal sur bruit (Signal to Noise Ratio, SNR) est faible, la performance se dégrade et nécessite donc un nombre d'échantillons plus élevé.
Frequency-Hopped, Sources, Sensor arrays, Angle of arrival
Mots clés
« Frequency-Hopped », sources, réseau de capteurs, angle d'arrivée
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