National Severe Storms Laboratory school of school of electrical and computer engineering electrical and computer engineering Techniques for Detection and Tracking Airplanes Techniques for Detection and Tracking Airplanes Using WSR-88D Using WSR-88D Svetlana Bachmann, Dusan Zrnic, National Severe Storm Laboratory, NOAA, Norman, OK Victor DeBrunner, Mark Yeary, School of Electrical and Computer Engineering, The University of Oklahoma, Norman, OK [email protected], [email protected], [email protected], [email protected] radar set radar set up up 6 For the first time, weather radar echoes from point scatterers (airplanes) in a non-stormy environment are investigated in the time and frequency domains and compared to model simulations to build a background for differentiating these echoes from weather signals and to develop procedures for data censoring. The NWS network of WSR-88D covers the entire US – WSR-88D operate continuously Awareness about security – can weather radar detect and track non-cooperative targets, e.g. airplanes ? abstra abstra ct ct KOUN WSR-88D • RF = 2705 MHz • P t = 750 kW • Parabolic, d = 8.5 m • Beam-width 0.95° • Short/long pulse • H, H/V polarization • 381.3 m ASL Time series data collected by KOUN for Homeland Defense Radar Test on March 26 2003 10 10 Z e Z 2 ln 16 4 2 2 1 6 2 r c K Z e 2 ln 2 | | 2 2 2 10 2 2 1 3 2 l r Z K c g P P e t 2 4 3 4 2 2 4 ) , ( l r f g P t distributed scatterers point scatterers |K| 2 = 0.93 = 1.57 s 1 = 0.95/180 rad = 0.1 m -40 -20 0 20 40 0 5 10 15 20 25 30 35 40 45 -1 2400 rpm, v = 41 m s –1 A = 2, B = .5, C = 248 weighted with the Hanning window Power (dB) -40 -20 0 20 40 -40 -30 -20 -10 0 10 20 30 40 50 weighted with the Hanning window Velocity (m s –1 ) Power (dB) -40 -20 0 20 40 -80 -60 -40 -20 0 20 40 60 weighted with the Hanning window Velocity (m s –1 ) Power (dB) • Speed of flight • Moving parts: propeller (rpm), etc. • Turbulence • Position in the resolution volume ) ( exp ) ( exp 1 1 d d jk B jk B ) sin( 1 k C 60 2 RPM 1000..5000 rpm v d = 40..55 m s-1 A, B, C Aircraft can be tracked with weather radar Aircraft has signature in Doppler spectrum Doppler spectra corresponds to the physical characteristics of the craft: replicated spectral characteristics of Cessna 188 Ag Wagon. Categories of Airplanes could be distinguished Velocity (m s -1 ) simulati simulati on on airplane-1 airplane-1 spectra spectra airplane-2 airplane-2 spectra spectra model model 9 10 11 12 13 14 15 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 R ange (km ) H eightabove antenna (km ) 363 m motivati motivati on on Airplane-1 cut 13: away, 24 m s –1 1° at 15 km – 262 m, at 9 km – 157 m Airplane-2 cut 13: toward, 13 m s –1 toward, 40 m s –1 5 km 10 km Z, dB V, m s - 1 15 km 180 170 Trajectory tracking cross cross section section altitude altitude airplane in front of behind clear-air O O KLAHOM KLAHOM A A The university of The university of Cooperative Institute for Mesosc Meteorological Studies