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Airborne and Space borne SAR
Missions
Shefali Agrawal
Photogrammetry and Remote Sensing Department
EDUSAT Short Course on
Microwave Remote Sensing and its
Application (5th February 2014)
Microwave Remote Sensing
Microwave Remote Sensing
Active Passive
Sensing microwave radiation from earth
surface
Illuminates the target artificially and receives
signal after interaction with the target
Radiometer
Imaging Non-imaging
RAR
SAR
Altimeter
Scatterometer
Microwave Sensors
OPERATES FOR 1 mm TO 100 Cm
Because Of Longer Compared To Visible-IR, The Technology Of
Receiving And Transmitting In Microwave Region Is Different.
Antennas Are Used For Reception And Transmission.
Passive microwave sensor
Detects the naturally emitted
microwave energy within its field of
view. This emitted energy is related to
the temperature and moisture
properties of the emitting object or
surface.
Passive microwave sensors are
typically radiometers.
Applications: Snow cover mapping,
Flood mapping, Soil moisture
mapping.
The microwave energy recorded
by a passive sensor can be
emitted by the atmosphere (1),
reflected from the surface (2),
emitted from the surface (3),
or transmitted from the
subsurface (4).
Contd.. Because the wavelengths are so long, the energy available is quite small
compared to optical wavelengths.
Thus, the fields of view must be large to detect enough energy to record a
signal.
Most passive microwave sensors are therefore characterized by low
spatial resolution.
Special Sensor Microwave
Imager (SSMI)
4 frequencies --
19.35,
22.235, 37, and
85.5 GHz
Swath -- 1500km
Altitude – 835 km
Resolution ~
20km
Sea Ice Monitoring
IRS P4 Multi-frequency Scanning Microwave Radiometer (MSMR) band
characteristics
Frequencies
(GHz)
Polarization Resolution
(km)
Swath Sea Surface
Temperature
Accuracy
6.6 V&H 120x120
1360 km
1.3 degrees k 10.65 V&H 80x80
16 V&H 40x40
21 V&H 40x40
Active microwave sensor
It provide own source of microwave radiation to
illuminate the target.
divided into two categories: imaging (RADAR)
and non-imaging (altimeters and
scatterometers).
Non-imaging microwave sensors are profiling
devices which take measurements in one linear
dimension, as opposed to the two-dimensional
representation of imaging sensors.
It transmits a microwave (radio) signal towards
the target and detects the backscattered portion of
the signal.
RADAR :
RAdio Detection And
Ranging
Doppler Effect
•The frequency of an observed wave is affected by the
relative motion between source and observer
•Doppler effect is the apparent change in the receiver
frequency from the transmitted frequency as a function
of the relative velocity between transmitter and the
receiver
•If the two are moving towards each other the received
frequency will be higher than the transmitted
• In case of SAR the target experiences this shift in
frequency and return is also doppler shifted thus
producing a doppler shift to the return pulse
Doppler Effect
Frequency (pitch) of a wave changes if the receiver and/or
source are in motion relative to one another Train whistle has a increasing pitch as it approaches, highest when it is
directly perpendicular to the listener (receiver)
After train passes by, its pitch will decrease in frequency in proportion
to the distance it is from the listener (receiver)
This principle is applicable to all harmonic wave motion,
including the microwaves used in radar systems
There Are Four Main Frequencies Of Microwave Energy
Which Are Currently Used For Satellite Remote Sensing -
X-band: Uses A Wavelength Range From 2.4 To 3.8 Cm (12.5 TO 8 Ghz)
and is Widely Used For Military Reconnaissance and Commercially for
terrain surveys.
C-band: Uses A Wavelength Range From 3.8 To 7.5 Cm (8 TO 4 Ghz) and
used in ,many SPACEBORNE SAR, such as ERS-1 AND RADARSAT.
S-band: Uses A Wavelength Range From 7.5 TO 15 Cm (4 TO 2 Ghz) and is
used in ALMAZ.
L-band: Uses A Wavelength Range From 15 To 30 Cm (2 To 1 Ghz) used On
Seasat And Jers-1.
The Capability To Penetrate Through Precipitation Or Into A Surface Layer Is
Increased With Longer Wavelengths. Radars Operating At Wavelengths
Greater Than 2 Cm Are Not Significantly Affected By cloud Cover, however,
rain does become a factor at Wavelengths shorter Than 4 cm.
Active Microwave Sensors
•BISTATIC: When separate antennas are used for
transmitting and receiving
•MONOSTATIC: Same antenna is used for transmitting
and receiving
Radars For Remote Sensing
•NADIR LOOKING ( (Altimeters)
•SIDE LOOKING (SLAR and SAR)
Radar Angle Nomenclature
η
(a)
η
(b)
Depression angle: The angle of the radar beam to the target (i. e., line of sight
from the antenna to the target) measured from a horizontal plane (η)
Look angle: The angle of the radar beam to the target measured from a vertical
plane (θ).
Incidence Angle: Angle between the radar beam to the target and the
perpendicular to the ground surface, where the beam strikes (Φ). When the
surface is horizontal, the incidence angle and look angle are same. When the
surface is not horizontal, the terrain slope affects the local incidence angle. For a
horizontal surface, the incidence angle is least near range and maximum at far
range.
11/18/02 University of Kansas
RF Spectrum Microwave Radiometry covers a range of frequencies.
1 GHz 10 GHz 100 GHz 1000 GHz
Soil
Moisture
1-3 GHz
Resolution /
aperture
Atmospheric
Temperature
54, 118 GHz
Accuracy
Atmospheric
Water Vapor
22, 24, 92, 150,
183 GHz
Accuracy
Sea Surface Salinity
1-3 GHz
Receiver sensitivity/
stability
Precipitation
11, 31,37,89 GHz
Frequent global
coverage
Atmospheric
Chemistry
190, 240, 640,
2500 GHz
High frequency
Sea Ice
37 GHz
Polar coverage
Ocean Surface Wind
19, 22 GHz
Polarimetry
Cloud Ice
325, 448, 643 GHz
High frequency
30 cm 3 cm 3 mm 0.3 mm
L band S band C band X band Ku/K/Ka band Millimeter Submillimeter
Hartley, NASA
Polarisation
Polarisation Refers To The Orientation Of The Electric And Magnetic
Fields Of Electromagnetic Waves.
Radar Systes Can Be Configured To Transmit And Receive Either
Horizontally Or Vertically Polarised Electromagnetic Radiation.
When Transmitted And Received Energy Is Polarised In The Same
Direction, It Is Referred To As Like-polarised. Hh Refers To Horizontally
Transmitted And Received Energy; Vv For Vertically Transmitted And
Received Energy.
When Transmitted And Received Energy Is Polarised In Opposite
Directions, It Is Referred To As Cross-polarised. Hv Refers To Horizontal
Transmission And Vertical Reception; Vh For Vertical Transmission And
Horizontal Reception.
When The Radar Wave Interacts With A Surface, The Polarisation Is
Modified Based On The Properties Of That Surface. This Affects The Way
The Scene Appears On Radar Imagery.
Antennas
• Antennas are used to couple electromagnetic waves into
free space or capture electromagnetic waves from free
space.
Type of antennas
• Wire
• Dipole
• Loop antenna
•Aperture
• Parabolic dish
• Horn
dipole
Feed (primary radiator)
Reflector (secondary radiator)
feeding line (waveguide)
Parabolic antenna
• Antennas are characterized by their:
– Directivity : It is the ratio of
maximum radiated power to that
radiated by an isotropic antenna.
– Efficiency: Efficiency defines how
much of the power is the total power
radiated by the antenna to that
delivered to the antenna.
Antennas
– Gain : It is the product of
efficiency and directivity
– Beamwidth :Width of the
main lobe at 3- dB points.
Satellite Borne Microwave Radiometer
An Imaging Microwave Radiometer Essentially Consists Of
An Antenna, Which Receives The Incoming Radiation
A Scanning Mechanism – Mechanical Or Electrical
A Receiver And Associated Electronics, Which Detects And
Amplifies, The Received Radiation And Produce A Voltage
Output.
In-flight Calibration Systems – Hot Body, Sky Horn, Etc.
Auxiliary Logic Systems Providing Signals For Timing,
Multiplexing Data Formatting, Etc.
House-keeping Systems, Which Monitors Various
Temperatures, Voltages, Etc.
RADAR – Radio Detection And Ranging
Radar Remote Sensing Techniques Can Provide Information About
The Earth’s Surface Related To:
- Surface Roughness
- Topography
- Moisture Conditions (Dielectric Constant)
A Radar System Has Three Primary Functions:
- It Transmits Microwave (Radio) Signals Towards A Scene;
- It Receives The Portion Of The Transmitted Energy Backscattered
From The Scene; And
- It Observes The Strength (Detection) And The Time Delay
(Ranging) Of The Return Signals.
SAR Imaging Modes
ScanSAR mode is an additional mode that has been defined by some SAR data
providers. ScanSAR is not a true Scan mode, - special case of the stripmap mode.
ScanSAR incorporates a process for time-sharing an electronically steered phased array
antenna to quickly move the beam from one strip to a parallel one so that multiple strips can
be illuminated in one pass.
ScanSAR modes have poorer resolution. The strips are typically processed into slightly
overlapping images that are then “stitched” into large area images
Non-imaging Sensors
Altimeter
Nadir-looking AMI, measures height of the targets from the
two-way travel time.
Applications: Ocean surface topography, Wave height; May be
configured to measure terrain elevation.
Scatterometer
Side-looking AMI, measures scattering co-efficient of the
targets; provides data across flight direction.
Applications: Ocean surface wind speed and direction.
Radar Altimeter Is A Short Pulse Radar Used For Accurate Height
Measurements.
• Ocean Topography.
• Glacial Ice Topography
• Sea Ice Characteristics
Scatterometer
A Scatterometer is an Active Radar Instrument
• Transmits A Pulse Of Known Power And Duration
• Receives And Measures The Power Return From The Surface.
Measures Radar Backscatter From Surface
• Backscatter Measurement provides Information on the Surface
Roughness
• Can Be Correlated To Geophysical Quantities
Past and Current Radar Altimeter Satellites
Satellite/Mission Years Organisation Accuracy
SKYLAB 1972 NASA 20 m
GEOS-3 1975-1978 NASA 3 m
SEASAT 1978 NASA 2 m
GEOSAT 1985-1990 US Navy 30 cm
ERS-1 1991-1996 ESA 4-10 cm
ERS-2 1995-2006 ESA 4 cm
Topex/Poseidon 1992-2005 NASA/CNES 2 -3 cm
GFO 2000-Present US Navy 2 - 5 cm
Satellite/Mission Years Organisation Accuracy
JASON1/2 2001-Present NASA/CNES 2 -3 cm
ENVISAT 2002-Present ESA 2 -3 cm
Cryosat-2 2010-Present ESA 2 -3 cm
SARAL/AltiKa 2013-Present ISRO/CNES 2 -3 cm
Characteristics of some of the Spaceborne Altimeters.
* second frequency
Non-imaging Sensors
Altimeter
Nadir-looking AMI, measures height of the targets from the
two-way travel time.
Applications: Ocean surface topography, Wave height; May be
configured to measure terrain elevation.
Scatterometer
Side-looking AMI, measures scattering co-efficient of the
targets; provides data across flight direction.
Applications: Ocean surface wind speed and direction.
SAR Systems
Airborne SAR
TOPSAR (JPL, USA), IFSARE(ERIM/Intermap, USA), DO-
SAR(Donier, Germany), E-SAR(DLR, Germany), AeS-1(Aerosensing,
Germany), AER-II (FGAN, Germany), C/X-SAR (CCRS, Canada),
EMISAR (Denmark), Ramses (ONERA, France), ESR (DERA, UK)
Space Borne SAR
Planetary SAR
Chandrayaan, Magellan (US, 1990-1994), Titan Radar Mapper (US,
2004), Arecibo Antenna, Goldstone antenna
SENSOR FREQ. GLOBAL MISSIONS ISRO
SAR
L SEASAT,SIR-C, JERS-1,PALSAR, MAPSAR CY-2 L-Band MoonSAR,
RISAT-3 SAR
S CASSINI Chandrayaan-1 MiniSAR
CY-2 S-Band MoonSAR
C ERS-1/ERS-2, SIR-C, ENVISAT-ASAR,
RADARSAT-1, RADARSAT-2
RISAT-1 SAR,
ASAR, DMSAR,
RISAT-1A SAR,
X SIR-C, TERRASAR-X, TECSAR RISAT-2
DMSAR, RISAT-4 SAR
SCATT C/Ku (Fan) SEASAT, ERS-1/ERS-2,NSCAT, METOP ------
Ku (Pencil) QuickScat , Seawinds ( Midori-II) OCEANSAT-2, SCATT-2
ALT. Ku / Ka Seasat, ERS-1/2,Topex, Jason, Envisat-RA ALTIKA
Radiometer 6- 160 Ghz SSMI, AMSR, ATMS, CMIS MSMR, MADRAS (MT)
SOUNDER Temp/Humdty
23-190 Ghz
AMSU-A/B, HSB, ATMS, CMIS SAPHIR (MT)
MAPS (TSU & HSU)
Pol. RAD 6 – 37 Ghz WindSAT, ATMS,CMIS ---------
Synthetic
Aper. RAD
L-band ,
Sounder
MIRAS(SMOS), GeoSTAR SARAD
Weather
Radar
18, 37, 94 Ghz PR (TRMM), PR-2 ( GPM), CloudSat --------
Missions Involving Microwave Sensors
Airborne SAR sensor • AIRSAR
• The Airborne Synthetic Aperture Radar (AIRSAR) is a side-looking
radar instrument mounted on modified NASA DC-8 aircraft.
• It was an all-weather imaging tool able to penetrate through clouds and
collect data at night.
• AIRSAR was designed and built by the Jet Propulsion Laboratory
(JPL). It can collect fully polarimetric data (POLSAR) at three radar
wavelengths: C-band (0.057 m), L-band (0.25 m), and P-band (0.68
m).
Radar C band L band P band
Frequency 5.3 GHz 1.3 GHz 440 MHz
Polarimetry Quad Quad Quad
Interferometr
y
XTI,ATI XTI,ATI --
Height
Accuracy
1m / 5m 2m / 10m --
Velocity
Accuracy
10 cm/s 10 cm/s --
Bandwidth 20 MHz 40 MHz 80 MHz
Radar C/L/P C/L/P L
Swath 20km 10km 6km
AuSAR -INGARA
• The INGARA Australian Airborne Radar Surveillance
System, formerly called AuSAR, is a low cost airborne
imaging radar technology demonstrator under development
at the Defence Science and Technology Organisation in
Adelaide, Australia. The aims of INGARA is primarily for
aid in defence applications
Radar X band
Frequency 10.1 GHz
Incidence Angles 45º -89º
Polarimetry Quad
Interferometry ATI
Stripmap Mode 2 m resolution
Spotlight Mode <1 m resolution
Swath 12 km
Airborne SAR development in ISRO
C – band Airborne imaging SAR (ASAR) has been developed indigenously
(1990)
Generates image with 6 metres range & Azimuth resolutions and
having 25 Kms swath
C-band DMSAR First flown on NOV-26, 2005
Operating frequency 5350 MHz
Polarisation HH, VV
Slant range resolution 1 m (Exp), 3 m, 5 m, 10m
Azimuth resolution 1 m (Exp), 3 m, 5 m, 10m
Swath coverage 6 Km (Exp), 25 km, 50 km, 75 km
Các vệ tinh SAR
SEASAT
(1978)
ERS - 1
(1991 - 2000)
JERS - 1
(1992 - 1998)
SIR-C/X-SAR
(1994)
RADARSAT - 1
(1995)
ERS - 2
(1995) SRTM
(2000)
ENVISAT
(2002)
ALOS / PALSAR
(2006)
TerraSAR–X (2007) &
TanDEM-X(2010) RADARSAT - 2
(2007)
SAR - Lupe
(2005)
Spaceborne SAR
RISAT-1
(2012)
RISAT-2
(2009)
Satellite and Sensors
Contd..
1- Envisat polarizations HH or VV or HH+VV or HH+HV or VV+VH
2- ALOS PALSAR polarizations HH or VV or HH+HV or VV+VH or HH+HV+VH+VV
3- SAOCOM polarizations HH or VV or HH+HV or VV+VH or HH+HV+VH+VV
4- RADARSAT-2 polarizations HH or VV or HV or VH or HH+HV or VV+VH or HH+HV+VH+VV
X band
N
a
t
i
o
n
Sensor/Agency Orbit
altitude
Inclination/
revisit
Swath Imaging Modes Spatial
resoluti
on
Incidenc
e angle
G
E
R
M
A
N
Y
SAR Lupe 1-5 -DLR/Bundeswehr
5 satellite collecting high
resolution SAR images for
military reconnisance
2006,2007(2&3), 2008(4&5)
Polar
500Km
98.2
daily
8
5.5
Strip mode
Spot light Mode
<1
TERRA SAR X -DLR 2007-2013
Scientific and commercial use
hydrology, geology climatology,
oceanography, environment ,
disaster etc
Sun Sync
514 Km
97.44
11 days
10
10
15-30
100
High resolution spot
light SP(HH/ VV) or
DP(HH/VV)
Stripmap SP(
HH/VV/HV/VH
Scan SAR
1.48-3.49
1.48-3.49
1.7-3.49
1.7-3.49
20-55
20-55
20-45
20-45
Left and
right
looking
TAN DEM X-DLR 2010-14
Global DEM Generation and new
application using along track
InSAR and Pol In SAR
Sun Sync
514 Km
97.44
11 days
30
10
100
Bistatic mode
Monostatic
Along track InSAR
Pol INSAR
Stripmap DP
Spot light DP
ScanSAR DP
12m
DEM
<2m
3
1
16
25-55
• Active sensor (all radar sensors)
– Transmit microwave pulses to earth surface, measures amount of
energy that bounces back
• Pixel values (intensities) represent ability of target to backscatter (reflect)
pulses: 0-255 digital number
– Ability to collect data day or night
• One-channel image (RADARSAT-1)
– Single microwave frequency (5.3 GHz)
• C-Band, 5.6 cm wavelength
– Ability to collect data regardless of atmospheric conditions
• Horizontal Polarization (HH)
– Combine with multi-date and/or multi-sensor images
• Change detection, composite images
RADARSAT-1
RADARSAT-1
RADARSAT International 1996. Radarsat Geology Handbook. Richmond, B.C.
Image Product Options: 35 possibilities
Positions – cross-track viewing incidence angles 10° - 60°
RADARSAT-1
• Temporal resolution
– 24 day orbit path repeat cycle
– With RADARSAT’s suite of beam modes, images
can be acquired for a location every one (high
latitudes) to five (low latitudes) days
• Spatial coverage depends on beam mode
Beam Mode (35 Possibilities) Coverage (km) Spatial Res. (m)
ScanSAR Wide (1) 500 x 500 100
ScanSAR Narrow (2) 300 x 300 50
Extended Low (1) 170 x 170 35
Wide (3) 150 x 150 30
Standard (7) 100 x 100 25
Extended High (6) 75 x 75 25
Fine (15) 50 x 50 8
RADARSAT International 1996. Radarsat
Geology Handbook. Richmond, B.C.
RADARSAT 1 IMAGING MODES
Mode Resolution(M)
Range X
Azimuth (M)
Looks Width
(Km)
Incidence Angle
(Degrees)
Standard 25 x 28 4 100 20-49
Wide - 1 48-30 x 28 4 165 20 - 31
Wide - 2 32-25 x 28 4 150 31 - 39
Fine resolution 11-9 x 9 1 45 37 - 48
ScanSAR
narrow
50 x 50 2 - 4 305 20 - 40
ScanSAR wide 100 x 100 4 - 8 510 20 - 49
Extended (H) 22-19 x 28 4 75 50 - 60
Extended (L) 63-28 x 28 4 170 10 - 23
ASAR - Advanced Synthetic Aperture Radar
(ENVISAT, European Space Agency)
• The ESA's ENVISAT satellite was successfully launched
on 1st March 2002, with the Advanced SAR (ASAR)
instrument
• Operates in C-band (5.331 GHz).
• swath coverage of over 400km wide using ScanSAR
techniques.
• In the image mode, ASAR operates in one of seven
predetermined swaths (100 km swath width) with either
vertically or horizontally polarized radiation; the same
polarization is used for transmit and receive (i.e., HH or
VV).
• The ground resolution is about 30 m (three looks)
ALOS (1/2) Spacecraft Mass Approx. 4 tons
Generated Power Approx. 7 kW (at End of Life)
Design Life 3 -5 years
Orbit
Sun-Synchronous Sub-Recurrent
Repeat Cycle: 46 days
Sub Cycle: 2 days
Altitude: 691.65 km (at Equator)
Inclination: 98.16 deg.
Attitude Determination
Accuracy 2.0 x 10-4degree (with GCP)
Position Determination
Accuracy 1m (off-line)
Data Rate
240Mbps (via Data Relay Technology
Satellite)
120Mbps (Direct Transmission)
Onboard Data Recorder Solid-state data recorder (90Gbytes)
ALOS
Instrument Acronym
Panchromatic Remote-sensing
Instrument for Stereo Mapping
PRISM
Advanced Visible and Near
Infrared Radiometer type 2
AVNIR-2
Phased Array type L-band
Synthetic Aperture Radar
PALSAR
RADARSAT 2
Geometry near-polar, sun-synchronous
Altitude 798km
Inclination 98.6 degrees
Period 100.7 minutes
Repeat cycle 24 days
Orbits per day 14
Frequency Band C-band (5.405 GHz)
Channel Bandwidth 11.6, 17.3, 30, 50, 100 MHz
Channel Polarization HH, HV, VH, VV
SAR Antenna Dimensions 15m x 1.5m
Radarsat-2 launched December 14, 2007
• Multiple polarization modes, including a fully-polarimetric mode in which
HH, HV, VV and VH polarized data are acquired.
• Its highest resolution is 1 m in Spotlight mode (3 m in Ultra Fine mode) with
100 m positional accuracy requirement.
• In ScanSAR Wide Beam mode the SAR has a nominal swath width of 500 km
and an imaging resolution of 100 m
Beam Mode Nominal
Swath Width
Approximate Resolution
(Range) (Azimuth)
Approximat
e Incidence
Angle
Polarization
Ultra-Fine 20 km 3 m 3 m 30° - 49° Single
Polarization Multi-Look Fine 50 km 8 m 8 m 30° - 50°
Fine 50 km 8 m 8 m 30° - 50° Single
Polarization
OR
Dual
Polarization
Standard 100 km 25 m 26 m 20° - 49°
Wide 150 km 30 m 26 m 20° - 45°
ScanSAR
Narrow
300 km 50 m 50 m 20° - 46°
ScanSAR Wide 500 km 100 m 100 m 20° - 49°
Extended High 75 km 18 m 26 m 49° - 60° Single
Polarization
Fine Quad-Pol 25 km 12 m 8 m 20° - 41° Quad
Polarization Standard Quad-
Pol
25 km 25 m 8 m 20° - 41°
RADARSAT 2 IMAGING MODES
TERRA SAR X
• TerraSAR-X is an X-band SAR mission for scientific research and
applications. It is the first satellite to be built in a public/private
partnership in Germany Active phased array X-band SAR
X-Band Imaging Modes
HighRes SpotLight: 5 x 10 km, up to 1 m. spatial res.
SpotLight: 10 x 10 km, up to 2 m. spatial res.
StripMap: 30 km wide strip, up to 3 m. spatial res.
ScanSAR: 100 km wide strip, 16-18 m spatial res.
SAR (Synthetic Aperture Radar)
TOR Package (Tracking, Occultation & Ranging)
GPS Receiver
(LRR) Laser Retro-reflector Array
LCT (Laser Communication Terminal)
• TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement)
• TanDEM-X mission is launched on 21st June 2010, to generate a high-
accuracy global Digital Elevation Model (DEM). TanDEM-X is a second SAR
satellite flying in a tandem orbit configuration with TerraSAR-X. The
TanDEM-X mission's objectives are: (1) Generation of DEM (2) Along-track
interferometry (3) Bi-static applications (e.g., polarmetric SAR
interferometry).
TERRA SAR X imaging modes
Beam mode
SpotLight Mode StripMap Mode ScanSAR Mode
Waveband X-band (3.11 cm)
Polarization Single (VV or HH)
Dual
(VV&HH)
Single
Dual
(VV&HH or
HH&HV or
VV&VH)
Quad
(VV,HH,HV,VH)
Single
Highest ground
range resolution
1 m 3 m 16 m
Swath width 10 km 30 km 100 km
Antenna look
direction
Normally right
Incidence angle 20~55° 20~45°
Indian SAR Sensors
•ISRO first developed microwave sensors for atmospheric and ocean
applications called Satellite Microwave Radiometer (SAMIR)
Payload of Bhaskara series of satellites (1978,1981).
•Multi-frequency Scanning Microwave Radiometer (MSMR) and
scattero-meters onboard Oceansat 1 (1999)
•KU Band Scatterometer onboard Oceansat 2 (2009)
•Microwave Sounder on board Indian Mini Satellite
APPLICATIONS
• SEA SURFACE TEMPERATURE
• WIND SPEED
• CLOUD-LIQ WATER CONTENT
MSMR provided routinely 48 hour
global data product, in terms of
Brightness Temperature, SST, Wind
Speed, Water Vapor content and Cloud
Liquid Water, on operational basis from
National Remote Sensing Agency
(NRSA), Hyderabad, India.
MSMR (Multi Frequency Scanning Microwave
Radiometer) Launched on 26th May 1999
MSMR MISSION SPECIFICATIONS
Spacecraft IRS-P4
Orbit Sun Synchronous
Altitude 720 Km
Swath 1360 Km
Repeativity 2 days
Frequencies 6.6, 10.65, 18.0 & 21
GHz
Polarisation V & H for all
frequencies
Grid size
150 Km (6.6 GHz)
75 km (10.65 GHz)
50 km (18 and 21 GHz)
Sampling 12 bits
Data rate 5.6 kbps
Payload Weight 130 kg
Payload Power 80 Watts
RISAT-1 & RISAT-2 Parameters RISAT-2 RISAT-1
Country India India
Lifetime (Design) 5 years 5 years
Band X C
Wavelength (cm) 9.59 GHz 5.350 GHz
Polarization HH/VV HH, HV, VH, VV
Incidence angle (º) 20-45 12-55
Resolution 1-8 2-50
Swath width (Km) 5-55 25-223
Repeat Days 14 days 25 days
RISAT 1
•C band SAR 5.35 GHz: 5
imaging modes
•Single, dual and Quad
polarisation modes
•Sun Synchronous orbit
•Single Look Products (SLC) where
the amplitude and phase are
preserved will be available for single
beam mode.
•This image is Geotagged using orbit
and attitude information of the
satellite and is available in the CEOS
format
•Standard products are available as Ellipsoid Georeferenced Terrain corrected products with UTM
projection, WGS 84datum in CEOSS /GEOTIFF format
• Near-Real Time (NRT) processing and electronic delivery
Parameters
SSMR in NIMBUS-
7
SSM/I
IRS-P4, MSMR
EOS Aqua AMSR-
E
ADEOS-II AMSR
Launch date
1978-87
1987/92/95
May 26, 1999
May 4, 2002
Jan. 16, 2004
Frequency
(GHz.)
6.6, 10.7, 18.0, 21
and 37 GHz
19.3, 22.2 (V),
38.0 and 85.5
GHz
6.6, 10.65, 18,
21
6.6, 10.65, 18.7,
23.8, 36.5, 89
6.6, 10.7, 18.7, 23.8,
36.5, 89, (50.3 V and
52.8 V polarization)
Polarization
H & V
H &V (except
22.2 GHz)
H&V
H&V
H&V (except last 2)
IFOV (km x km)
148x95, 91x59,
55x41, 46x30,
27x18
69x43, 60x40,
37x28, 15x13 km
150x144, 75x72,
50x36, 50x36
km
76x44, 49x28,
28x16, 31x18,
14x8, 6x4 km
70x40,46x27,25x14,
28x17,14x8,6x3,10x
6 km
Swath width
(km)
822 km
1400 km
1360
1445
1600
Revisit
coverage(days)
--
1 day
2
2
2
Incidence
angle (deg.)
50.3 (at the
surface)
53.3 (at the
surface)
43.13
54 (at the
surface)
54 (at the surface)
Sensitivity
0.4, 0.5, 0.7, 0.7,
1.1
0.8, 0.8, 0.6, 1.1
0.6, 0.75, 1.05,
1.1
0.3, 0.6, 0.6, 0.6,
0.6, 1.0
0.3,0.6,0.6,0.6,0.6,1.
0,1.3,0.9
Radiometer Systems and their Parameters
Parameter \ Mode Spotlight Stripmap ScanSAR
Ultra-fine High-sensitive Fine
Frequency 1257.5 MHz 1257.5 MHz or 1236.5 / 1278.5 MHz, selectable
Incidence angle 8º to 70º range
Bandwidth 84 MHz 84 MHz 42 MHz 28 MHz 14 MHz
Ground resolution 3 m (rg) x 1 m
(az)
3 m 6 m 10 m 100 m
Swath 25 km (rg) x 25
km (az)
50 km 50 km
(FP:30 km)
70 km
(FP:30 km)
350 km
5 looks
Polarization SP SP/DP SP/DP/FP/CP SP/DP/FP/CP SP/DP
Data rate 800 Mbit/s 800 Mbit/s 800 Mbit/s 400 Mbit/s 400 Mbit/s
NESZ -24 dB -24 dB -28 dB -26 dB -26 dB
S/A: range 25 dB 25 dB 23 dB
FP:Co-pol: 23 dB
FP:X-pol: 15 dB
25 dB
FP:Co-pol: 20 dB
FP:X-pol: 10 dB
25 dB
S/A: azimuth 20 dB 25 dB 20 dB 23 dB 20 dB
Future Missions : ALOS 2- PALSAR 2
Thank You
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