DLR's Airborne F-SAR System Andreas Reigber Microwaves and Radar Institute
Why Airborne SAR? Advantages of airborne SAR: Airborne ‐ SAR • Higher SNR & resolution than spaceborne sensors • Flexible operation of the sensor • Experimental platform for new technology For the Institute: • Defining the „state ‐ of ‐ the ‐ art“ in SAR sensor development & demonstration of technology new technology • Prepare future satellite missions • Test and develop new signal processing algorithms • Development and demonstration of new demonstration of new techniques with existing spaceborne systems products and imaging techniques concepts for future spaceborne systems • Execution of scientific flight campaigns Slide 2
The Advanced Airborne Sensor F ‐ SAR Remarkable features: ‐ Very high resolution and SNR ‐ Multispectral operation (up to 4 bands) L-band X-band C-band P-band ‐ Polarimetry in all bands ‐ Single ‐ pass interferometry at X and S ‐ band ‐ Modular sensor design F-SAR technical characteristics Main Goals: X C S L P • Defining the „state ‐ of ‐ the ‐ art“ RF [GHz] 9.6 5.3 3.2 1.3 0.35 in SAR sensor technology BW [MHz] 800 400 300 150 100 • Scientific flight campaigns, preparation of PRF [kHz] up to 12 Rg res. [m] 0.2 0.4 0.5 1.0 1.5 new satellite missions Az res. [m] 0.2 0.3 0.35 0.4 1.5 • New approaches by multispectral & high ✓ ✓ ✓ ✓ ✓ PolSAR resolution PolSAR imaging Rg cov [km] 12.5 (at max.bandwith) Sampling 8 Bit real; 1000MHz; 4 channels. Slide 3
The Advanced Airborne Sensor F ‐ SAR DLR’s New F ‐ SAR Sensor 1H 1V 2H 2V 3H 3V 1H 1V 2H 2V 1H 1V 1H 1V 1H 1V X1H X1V X2H X2V X3H X3V S1H S1V S2H S2V C1H C1V L1H L1V P1H P1V X-Band S-Band C-Band P-Band L-Band L-Band SC-Band P-Band Antenna Switch Antenna Switch Antenna Sw. Antenna Sw. Antenna Sw. HPA Rack D Rack A E2a D3u, D3o D4 A3 F3 F1 7 S1 L-Band SC Ant. Sw. D2 UPC R1X R2X R1S R2S R1C R2C R1L R2L R1P R2P F5 F5 L-Band A5 P-Band X-Band SC XCS S1 P-Band Down Conv. Down Conv. L-Band TWTA TWTA Down Converter L HPA E3 E1 D1 Rack F A1 Chirp F5 2 of 4 Switch C6 8 S2 1 R1 2 R2 3 S1 4 S2 5 R5 6 R6 XCS-Band ADC ADC STC/AGC ADC ADC P-Band UPC ADC1 ADC2 Processor ADC5 ADC6 UPC C5 C5 C5 C5 A5 E4 C5 X-Band S1,2 Rack E XCS P Monitor Bus MDR MDR Onboard MDR MDR Chirp Chirp E4 MDR1 MDR2 Processor MDR5 MDR6 A5 C3 C3 C7 C3 C3 modular F ‐ SAR Navigation & System DC/AC Power Disk Array 1 Disk Array 2 Timing Unit Flight Guidance Control Supply B2 C6 B2 cabin layout system layout C1 System C2 B4 F-SAR Basic Configuration (Rack B and Rack C) X ‐ band C/S ‐ band L ‐ band P ‐ band F ‐ SAR core modules rack rack rack rack Slide 4
F ‐ SAR „in action“ (mounted on research plane Do228)
Simulation of Future Spaceborne Products Kaufbeuren (Germany) Kaufbeuren (Germany) Kaufbeuren (Germany) TerraSAR ‐ X, X ‐ band VV, HRS mode F ‐ SAR, X ‐ band, VV polarisation F ‐ SAR, X ‐ band quadpol (HH, VV, HV) Slide 6 1.0 m x 2.0m resolution 0.25m x 0.25m resolution 0.25m x 0.25m resolution
Simulation of Future Spaceborne Products Oensingen (Switzerland) F ‐ SAR, S ‐ Band quadpol (HH, HV, VV) Slide 7 0.5m x 0.65m resolution, 5 looks
Real ‐ time Situation Monitoring F ‐ SAR (DLR ‐ HR) weather independent real ‐ time onboard processing day & night capability Data distribution to end ‐ users (BOS, THW, red cross) through central platform data downlink: 1.25 GBit/sec (DLR ‐ KN) laser / microwave Slide 8
Slide 9 Real ‐ time Situation Monitoring Real-time Situation Monitoring
InSAR: Generation of digital elevation models Kaufbeuren (Germany) Kaufbeuren (Germany) Slide 10 Tandem ‐ X Digital Surface Model F ‐ SAR Digital Surface Model
InSAR: Generation of digital elevation models InSAR DEM Laser DEM 2 2 InSARDEM (Scale around: 41m) Laser (Scale around: 41m) 2 2 InSAR DEM INSARDEM XS (Scale around: 41m) Laser DEM 0 0 Muriel 4 Laser DEM ALS 26032013 (Scale around: 41m) ‐ 4 4 -2 -2 ‐ 2 ‐ 2 InSAR DEM Laser DEM Difference INSARDEM XS (Scale around: 41m) ALS 26032013 (Scale around: 41m) 4 4 µ = ‐ 0.15m σ = 0.11m 4 4 Difference Difference [-1m,1m] Northing 0 0 Northing Easting Testsite: Jade Bight F ‐ SAR Digital Surface Model ‐ 4 ‐ 4 -4 -4 vs. ALS Reference Heights Easting µ = 0.21m σ = 0.22m
DInSAR: Measurement of Ground Deformation / Motion Aletsch glacier (Switzerland) 85 cm / day 1 ‐ day ice motion SWISAR campaign (2006 & 2007) DINSAR campaign (2009) 20-40 cm / year Hamm (Germany) Slide 12 deformation within 6 months
Polarimetric Interferometry: Estimation of Forest Height and Biomass RGB = L/X/P-Band PolInSAR bl 1 z 2 S S HH HV [ 1 S ] S S VH VV n S S r HH HV [ 2 S ] S S VH VV h x y Azimut Estimated Forest Height L-band HH Courtesy of K. Papathanssiou
Polarimetric Interferometry: Estimation of Forest Height and Biomass Courtesy of Fichtelgebirge / Germany Corridor / Spain Bayrischer Wald / Germany Traunstein / Germany Oberpfaffenhofen / Germany
3D SAR Tomography • Innovative method for3D ‐ imaging • Possible applications: • Vegetation structure, biomass • 3D City models • Archeology N parallel tracks z (ca. 5 ‐ 20) n L r H n x y Slide 15
Stripmap SAR Circular SAR Imaging • Possibility of extremly high resolution (up to λ /4, i.e. about 6cm at L ‐ band) • Possibility of “holographic” 3D imaging • Possibility of continous imaging (“video SAR”) z r ≈ 6km Circular SAR 360 ° y illumination x antenna illumination Slide 16
Circular SAR Imaging: Continuous Monitoring X ‐ Band C ‐ Band
Polarimetric P-band Sounding • Dedicated imaging mode for deep sounding of ice / bedrock structure • Long wavelength can penetrate very deep in dry (i.e. cold) ice. • Identical antennas as in SAR mode, but nadir ‐ looking by modified feed network. ~ 570m bedrock clutter? clutter HV polarisation (single acquisition, low altitude) 32 km Spitzbergen (Nordaustlandet) Sounder Image, P ‐ Band 350MHz
Holographic Ice Sounding / Multi-circular SAR P ‐ Band L ‐ Band ARCTIC15 Kangerlussuaq / K ‐ Transect Fully polarimetric HoloSAR images. F ‐ SAR CAMPAIGN Pauli decomposition R,G,B = HH ‐ VV, HV, HH+VV. April ‐ May 2015
Bistatic SAR Imaging & Processing • Development of synchronisation techniques in preparation of TanDEM ‐ X • Development of new processing concepts (BFFB ‐ bistatic fast factorised back ‐ projection) monostatic bistatic v=7000m/s v=7km/s v=85m/s v=85m/s monostatic bistatic TerraSAR-X (Tx) F-SAR (Rx) space-/airborne bistatic image bistatic geometry azimuth resolution 0.5m Slide 20
Airborne ‐ SAR Campaigns (since 2001) ? Agriculture (crop parameters, soil moisture) Forestry (forest heights and biomass) Surveys over sea and land ice Sea topography and oceanography Slide 21
Mission Proposal for Environment and Climate: Advanced high‐performance SAR‐Technology: • Fo Format ation fligh flight wi with tw two SAR SAR ‐ sa satellit llites • Polarim larimetric tric in interf rferometry ry and and to tomo mography • Di Digi gital Beam Beamform rming wi with lar large refle flect ctor an antenna nna
F ‐ SAR Campaign ARCTIC/DALOX (May 2015) • 11 test ‐ sites in Greenland • Analysis of several novel methods for the estimation of snow and ice parameters • Evaluation of high ‐ resolution SAR for security applications in Arctic environments • Study of the stongly varying penetration capabilities of the different bands into snow and ice • Demonstration of multi ‐ spectral SAR data recording in 4 frequency bands Campaign test sites • Acquisition of unique data sets for further research
L ‐ Band S ‐ Band X ‐ Band ARCTIC15 Helheim Glacier, differences in L ‐ , S ‐ and X ‐ band. Fully polarimetric images. F ‐ SAR CAMPAIGN Pauli decomposition R,G,B = HH ‐ VV, HV, HH+VV. April ‐ May 2015
L ‐ Band S ‐ Band X ‐ Band ARCTIC15 Helheim Glacier, differences in L ‐ , S ‐ and X ‐ band. Fully polarimetric images. F ‐ SAR CAMPAIGN Pauli decomposition R,G,B = HH ‐ VV, HV, HH+VV. April ‐ May 2015
X ‐ Band Increasing penetration depth C ‐ Band L ‐ Band P ‐ Band (non ‐ simultaneous) ARCTIC15 K ‐ Transect ‐ Percolation zone Fully polarimetric images. F ‐ SAR CAMPAIGN Pauli decomposition R,G,B = HH ‐ VV, HV, HH+VV. April ‐ May 2015
L ‐ Band S ‐ Band X ‐ Band ARCTIC15 Sea Ice between Greenland and North America Fully polarimetric images. F ‐ SAR CAMPAIGN Pauli decomposition R,G,B = HH ‐ VV, HV, HH+VV. April ‐ May 2015
ARCTIC15 Godhavn, X ‐ band detail image, 25cm resolution Fully polarimetric images. F ‐ SAR CAMPAIGN Pauli decomposition R,G,B = HH ‐ VV, HV, HH+VV. April ‐ May 2015
BIOMASS: ESA Earth Explorer Mission ESA EE-7 to map forest above-ground biomass and its changes System : Fully-polarimetric P-band SAR 12 m reflector antenna Strip-map acquisition mode with 6 MHz bandwidth Spatial resolution: 60 x 50 m with 6 ENL Launch planned for 2021 PolSAR Pol-InSAR Combined TomoSAR
Recommend
More recommend
