Post on 01-Jan-2017
Air Systems Division
High Doppler Resolution X-bandWake-Vortex Radar : CDG Airport Trials F. BARBARESCO
Air Systems Division
Brieve History of Wake Vortex Radar Campaigns
Air Systems Division3
GEC MARCONI EXPERIMENT (UK) : 1992GEC-MARCONI DX 04 Radar (S Band)Wake Vortex have been clearly detected (measured RCS : -80 dBsm to –90 dBsm) at 2.8 Km by radar (radar beam perpendicular to the aircraft’s flight path)DX Radar Figures :3 GHz (λ=9 cm)PRI = 100 μsτc= 4 μs (B=0.25 MHz, 600 m) to 13 ns (B=77 MHz, 2 m)τ< 400 . τcPc = 10 KWτ/PRI < 2.5 %GEmGRec= 33 dB
Radar Beam Position
HS-748 Plane :
Width : 30.02 m
Weight : 40000 LBS
Speed : 138 kts (69 m/s)
Weather conditions :
Cloud base : 2500 feet
Humidity : 85%Doppler Spectrum(range cells : 15 m)
Air Systems Division4
CNRS/CRPE, CNET & STNA (France) : 1992PROUST RadarFrequency : 961 MHzWavelength : 31.2 cmPRI = 156.4 μsτ = 1 μsPc = 4.5 KWResrange = 150 m (withoutpulse compression)τ/PRI < 2.5 %Beamwidth : 5°Gant = 29 dBRangeamb = 23.4 Km
Doppler Spectrum(range cells : 30 m)
Air Systems Division5
CLEAR AIR RADAR REFLECTIVITY OF WAKE VORTEXTests have revealed radar echoes in clear air.
Two mechanisms causing refractive index gradients are :Radial Pressure (and therefore density) gradient in a columnar vortex arising from the rotational flow :
Adiabatic transport of atmospheric fluid within a descending oval surrounding a vortex pair :
Particulates were not involved (not f4 Rayleigh scattering) .The frequency dependence was not the Kolmogorov f1/3
The role of Engine Exhaust :RCS doesn’t change when the engine run at idle or full powerExhaust diameter yields a partial pressure of vapour and a contribution which is much smaller than that due to temperature.
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Air Systems Division
THALES RADAR WAKE VORTEX PROCESSING CHAIN
Air Systems Division7
CHARACTERISTICS OF THALES X-BAND BOR-A550 RADAR
Main FiguresFrequency : X Band (9.6 GHz for ORLY Campaign)Minimal Range : 400 mMaximal Range : 40 KmRange Resolution : 40 mMechanical Tilt : +/- 24°Beam Width (elevation/azimut): 4°/2.7°Radial Velocity Range : +/- 26 m/sDoppler Resolution (& High Resolution) : 0.2 m/s
(0.04m/s)Mechanical Scan Rate : 8°/s (sur 45° pour ORLY)Peak transmit power: 75 WData Link : RS232 (x2), RS432 (x2), EthernetRecording System : All range cellsexternal link Ethernet 20 Gb/s
PRF = 3348 HzF=9.6 GHz
Vamb = λ.PRF/2Vamb = 52.31 m/s
(+/-26 m/s)
λ=c/F=3.125 cm
Air Systems Division8
Wake Vortex Detection in All weather Conditions
No Rain
Minimum Temperature 8 °
Maximum Temperature 14 °
Rain Rate 0 mmWind Speed 22 km/hWind Direction : South
Rain
Minimum Temperature 9 °
Maximum Temperature 12 °
Rain Rate 1.19 mmWind Speed 20 km/h
Wind Direction South-East
RCS of Medium Aircraft Wake Vortex : 0.01 m2 S/N ≈ 15 dB (Range = 600 m)
NO RAIN RAIN
Air Systems Division9
Speed Variance of Rain can measure
EDR & TKE(air turbulence)
Time (s)
0 m/s
+/-26 m/s
0 m/s
Tangential SpeedVersus Radius
SpiralGeometry
Cross-Wind Speed
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21
WAKE VORTEX PROFILING : RADAR DOPPLER ANALYSIS
Air Systems Division10
WAKE VORTEX PROFILING : WAKE VORTEX AGEPositive
Time/Dopplerslopes
ZeroTime/Doppler
slopes
NegativeTime/Doppler
slopesLow speedNegative
Time/Dopplerslopes
Air Systems Division11
Wake Vortex Circulation Computation
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Wake Vortex Doppler Frequencies Extraction(Pre-Processing : CFAR on Doppler axis)
Air Systems Division12
Wake-Vortex Detection based on Doppler Entropy criteriaIn the framework of Affine Information Geometry, Kähler metric is given by Hessian of Entropy, considered as Kähler Potential Function :
Entropy of Multivariate Gaussian Law of Zero Mean :
Entropy can be parametrized by reflection coefficients of complex AR model
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Power
Air Systems Division13
Thales Advanced Processing Chain: 3 Patents
Implemented in C language :3 times faster
than real time by“off-line” tests on 4 Threadswith Quadri-
Core PC
PRF = 3348 Hz
Implemented in Matlablanguage
Air Systems Division14
“Off-Line” Tests on 4-threads quadri-Core PCC-Code Code has been parallelizedon 4 threads by divided 31 Range cells in 4 Domains (1.2 km)Each Range Domain is processed on 1 threadRange Cell resolution : 40 m
C-Code implemented on 4 Threads is 3 time faster
than real time :
1 second processed in 300 ms
Air Systems Division15
Real-Time Implementation of THALES “Wake Vortex”Algorithms (e.g. : General-Purpose computing on Graphics Processing Units)
In Progress : Real-Time THALES Processing Chain
General PurposeGPU
Ethernet 20Gb/sDATLINK
THALES Processing chain (3 patents)THALES radar
HMI
PRF = 3348 Hz
Multi-CorePC
Air Systems Division16
LIDAR & RADAR WAKE VORTEX DOPPLER SPECTRUM
AngularRadar resolution
Doppler radarsignature
Doppler Lidarsignature
LIDAR WAKE VORTEX DETECTION
Post-processingNeeded for Wind
Inversion detection
Air Systems Division
Paris Airport Radar Trials
Air Systems Division18
Radar Sensor Campaigns funded by THALES
2006 : Paris Orly AirportFrom Mode S site (500 m from runway)Wake Vortex Monitoring during departuresWeather conditions : Winter (clear air, rain)
2007 : Paris Orly AirportFrom Thales Limours Testbed TowerWake Vortex Monitoring during arrivals (ILS Interception)Weather Conditions : Autumn (highly turbulent atmosphere)
2008 : Paris CDG AirportFrom Kbis Tower co-localized with Eurocontrol Lidar (2 mm Windtracer)Wake Vortex Monitoring during arrivals/departures on Closely Spaced Parallel runwaysWeather Conditions : Summer (very hot, rain)
Orly 2006
Orly 2007
CDG 2008
Air Systems Division19
BOR-A550 Radar View at Paris ORLY Airport Site
Air Systems Division20
PARIS ORLY WAKE VORTEX RADAR CAMPAIGN (2006)
Air Systems Division21
Orly Airport 2006 (runway monitoring for departure)
Air Systems Division22
Orly Airport 2007 (ILS Interception monitoring for arrival)
Air Systems Division23
Wake Vortex Monitoring based on HR Doppler
Vertical ScanningFrom Limours Tesbed
Tower (Orly ILS Interception : 1500 m)
Highly Turbulent Atmosphere !!
Wake VortexRollups Wake Vortex
Rollups
Color = Doppler Entropy E = - log det(R) (R : covariance matrice)
Air Systems Division24
CDG Airport 2008 (runway monitoring : departure/arrival)
08L
08R
26L
26R
27L
27R
HorizontalScanning
VerticalScanning
Air Systems Division25
Scanning strategies
Vertical Scanning
Horizontal Scanning
360° scanning
Air Systems Division26
Vertical Scanning: Monitoring of Arrival (2nd runway)
Wake Vortex Roll-up(Arrival)
DepartureArrival
East Configuration
Air Systems Division27
Vertical Scan: Monitoring of Departure (1rst runway)
Wake Vortex Roll-up(Departure)
DepartureArrival
West Configuration
Air Systems Division28
West Config. Procedure
From scan to scan : Departure
Air Systems Division29
Vertical Scanning
Air Systems Division30
Horizontal scanning
Air Systems Division31
Wake Vortex Position & Circulation (strength in m2/s) along runwayPosition des vortex au cours du temps
1200
1300
1400
1500
1600
1700
1 2 3 4 5 6 7
Numéro de balayage
Cas
e di
stan
ce
vortex 1 position
vortex 2 position
Circulation des vortex au cours du temps en m²/s
0
20
40
60
80
100
120
140
160
180
1 2 3 4 5 6 7
N uméro d e b alayag e
vortex1 circulat ionvortex2 circulat ion
5 s per scan (35 s)Position at 1500 m
Position des vortex au cours du temps
600
700800
9001000
11001200
1300
1 2 3 4 5 6
Numéro de balayage
Cas
e di
stan
ce
vortex 1 position
vortex 2 position
Circulation des vortex au cours du temps en m²/s
0
50
100
150
200
250
300
350
1 2 3 4 5 6
N uméro d e balayage
vortex1 circulat ionvortex2 circulat ion
5 s per scan (30 s)Position at 1000 m
With Cross-Wind Without Cross-Wind
Air Systems Division32
Thales Radar Trials SynthesisParis ORLY AIRPORT Campaign has proved that X-band Radar can :
Detect Wake Vortex (RCS of 0.01 m2 on medium aircraft) :In all weather conditions (wet & dry at short range < 2 Km)In Staring & Scanning ModeIn real Time / Update Rate of 11 s on 60° scan sector
Localize Wake Vortexin range/azimuthWith resolution : 40 m x 1°
Characterize Wake VortexGeometry (Spiral)Age (Young, mature, old, decaying)Strength : Circulation (m2/s)
Characterize ambient air (in Rain Conditions)Wind (based on Doppler & post-processing)Ambient Air Turbulence (EDR & TKE)
Air Systems Division33
X-band Radar PerformancesWake Vortex Monitoring in All Weather Conditions (light to heavy
rain, fog, turbulent atmosphere,…)Operational Use to track Wake Vortex (transport, decay, rebound) in extreme weather conditions :
Wind burst (wind under Cb, turbulent atmosphere, wind shear…)No Wind (foggy weather,…)
Non Operational Use for « Safety Case » by Data Collection :Risks Assessment according to extreme wind conditions and not only on mean wind conditions (extreme values statistics)Need for Wake Vortex Data in exhaustive cases of airport climatology(good/bad weather)
Fast Monitoring of very large volume (radar scanning) with high update rate (e.g. : 8°/s with mechanical scanning of BOR-A radar and faster with Electronic scanning)
Highly sensitivity of Radar : monitoring of Wake Vortex for « medium » (high % of A320) aircrafts and not only « heavy / super heavy » (requested for traffic mix of « very light jets »)
Air Systems Division34
Radar/Lidar Sensors
Radar & Lidar are complementary sensors in all weather operationsTHALES has proved by derisking campaign (Paris CDG-2008) that X-band Radar & Lidar are complementary for Wake Vortex Monitoring :
Lockheed Martin has proved by derisking Campaign (Westheimer Aiport) that X-band & Lidar are compementary for Wind Monitoring (& Wind-shear)
Air Systems Division
WAKE-VORTEX & WIND SENSORS BENCHMARK
Air Systems Division36
Suite of Sensors benchmarking THALES will supervise benchmarking of :
Wake Vortex Monitoring Sensors
Wind Monitoring Sensors
Others
In All Weather Conditions
EUROCONTROL
M-Scan & E-scan X-band Radars
2 μm Lidar
Polar X-band Radar
1.5 μm LidarWind Profiler
UHF Radar Wind Profiler
Ultrasonic Anemometers
Sodar
Air Systems Division37
Threshold
Touch-Down Area
Runway 3000 m / 60 m (typically)
Wind
Final Approach Fix (FAF)
ILS Interception Area
Altitude between 2000 and 6000 ft (typically)
H = 400 ft
400 m2500 m
25 000 m (13.6 NM)
ILS Glide Slope
ILS Glide Slope : 3° (5.2%) – 4°
Max course deviation : 2° Ie horizontal deviation at FAF : +/- 800m
5 500 m (3 NM)
Final Approach
Landing
Lidar Windprofiler
Sodar/RassT° Profiler
UHF Windprofiler
Anemometers
Lidar 3D Wind Tracer
X-bandRadar 3D
Wind Mnitoring
One Instance of Weather Sensors Deployment
Wind info
Fusion
Air Systems Division38
CDG : Surveillance Area
Air Systems Division39
WV Predictor
Approach/Departure : Ground wake detection, tracking & alert
WIMS(in TMA)
Data Broadcast
Data Broadcast
Pilot
WV Alarm
Approach & TowerController
WV controller HMI
Ground RadarHorizontal/Vertical scanning
of Runways
Ground RadarVertical scanning
of ILS interception Area(Entering of glide slope)
Data-Link(WV Alerts)
Limours trials 2007
Orly trials 2006 & CDG 2008
crosswind
crosswind
Air Systems Division40
Wake Vortex Alerts in THALES EUROCAT-T
WVAS enables Air Traffic Control to:Separate all aircraft down to radar separation minima without jeopardizing flight safetyIncrease the airports/runways capacityAddress Arrivals and/or Departures
WVAS will ingest Wake Vortex Monitoring Sensors data for Safety Net
Air Systems Division41
Acknowledgements
ADP Radar Team Jean-Paul LecorreJean-Marc ReceveauDaniel DuongGilbert Herbulot
DSNA Radar TeamAndré SimonettiAlfred HarterJean Jezequel
Direction des Aires Aéronautiques (ADP CDG) : Gérard BatistellaGuillaume Auquier
Air Systems Division42
Questions
HORIZONTAL SCANNING VERTICAL SCANNING