香港六合彩中特网

This article presents the results of a series of measurements of multistatic radar signatures of small UAVs at L鈥� and X鈥恇ands. The system employed was the multistatic multiband radar system, NeXtRAD, consisting of one monostatic transmitter鈥恟eceiver and two bistatic receivers. NeXtRAD is capable of recording simultaneous bistatic and monostatic data with baselines and two鈥恮ay bistatic range of the order of a few kilometres. The paper presents an empirical analysis with range鈥恡ime plots and micro鈥怐oppler signatures of UAVs and birds of opportunity recorded at several hundred metres of distance. A quantitative analysis of the overall signal鈥恡o鈥恘oise ratio is presented along with a comparison between the power of the signal scattered from the drone body and blades. A simple study with empirically obtained features and four supervised鈥恖earning classifiers for binary drone versus non鈥恉rone separation is also presented. The results are encouraging with classification accuracy consistently above 90% using very simple features and classification algorithms.