National Severe Storms Laboratory school of electrical and computer school of electrical and computer
engineeringengineeringTechniques for Detection and Tracking Airplanes Using Techniques for Detection and Tracking Airplanes Using
WSR-88DWSR-88DSvetlana 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, [email protected], [email protected], [email protected], [email protected]
radar set upradar set up
6
9
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 ?
abstracabstractt
KOUN WSR-88D• RF = 2705 MHz • Pt = 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
1010Z
eZ
2ln16 4
221
62
rcKZe
2ln2||
22210
221
32
lrZKcgPP et
243
422
4),(
lr
fgPt
distributed scatterers
point scatterers
|K|2 = 0.93 = 1.57 s 1 = 0.95/180 rad = 0.1 m
-40 -20 0 20 405
10
15
20
25
30
35
40
45
50DFT
Velocity (ms-1)
Pow
er (d
B)
-40 -20 0 20 400
5
10
15
20
25
30
35
40
45DFT((signal+noise)*VonHann)
Velocity (ms-1)
Pow
er (d
B)
2400 rpm, v = 41 m s –1
A = 2, B = .5, C = 248
weighted with the Hanning window
Pow
er (d
B)
-40 -20 0 20 40-60
-40
-20
0
20
40
60FFT
Velocity (ms-1)
Pow
er (d
B)
in front ofairplanebehindclear air
-40 -20 0 20 40-40
-30
-20
-10
0
10
20
30
40
50FFT*VonHann
Velocity (ms-1)
Pow
er (d
B)
weighted with the Hanning window
Velocity (m s–1)
Pow
er (d
B)
-40 -20 0 20 40-80
-60
-40
-20
0
20
40
60DFT
Velocity (ms-1)
Pow
er (d
B)
in front ofairplanebehindclear air
-40 -20 0 20 40-80
-60
-40
-20
0
20
40
60DFT(signal*VonHann)
Velocity (ms-1)
Pow
er (d
B)
weighted with the Hanning window
Velocity (m s–1)
Pow
er (d
B)
• Speed of flight• Moving parts: propeller (rpm), etc.• Turbulence• Position in the resolution volume
)(exp)(exp 11 dd jkBjkB
)sin(1 kC
602 RPM
1000..5000 rpm vd = 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)
simulationsimulation
airplane-1 airplane-1 spectraspectra
airplane-2 airplane-2 spectraspectra
modelmodel
9 10 11 12 13 14 150
0.1
0.2
0.3
0.4
0.5
0.6
0.7
01
2345678
9101112131415
16 17 18 19
Range (km)
Hei
ght a
bove
ant
enna
(km
)
363 m
motivatiomotivationn
Airplane-1 cut 13: away, 24 m s–1
1° at 15 km – 262 m, at 9 km – 157 mAirplane-2 cut 13: toward, 13 m s–1toward, 40 m s–1
5 km
10 km
Z, dB V, m s-1
15 km
180 170
Trajectorytracking
cross cross sectionsection
altitudealtitude
airplanein front of
behindclear-air
OOKLAHOMKLAHOMAAThe university ofThe university of
Cooperative Institute for Mesoscale Meteorological Studies