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