Skip to main content

India remote sensing


1. Foundational Phase (Early 1970s – Early 1980s)

Objective: To explore the potential of space-based observation for national development.

  • 1972: The Space Applications Programme (SAP) was initiated by the Indian Space Research Organisation (ISRO), focusing on applying space technology for societal benefits.

  • 1975: The Department of Space (DoS) was established, providing an institutional base for space applications, including remote sensing.

  • 1977: India began aerial and balloon-borne experiments to study Earth resources and assess how remote sensing data could aid in agriculture, forestry, and hydrology.

  • 1978 (June 7): Bhaskara-I launched by the Soviet Union — India's first experimental Earth Observation satellite.

    • Payloads: TV cameras (for land and ocean surface observation) and a Microwave Radiometer.

    • Significance: Proved that satellite-based Earth observation was feasible for India's needs.

  • 1981 (November 20): Bhaskara-II launched.

    • Improvements: Enhanced radiometric and optical sensors for land use, forestry, and hydrology.

    • Outcome: Successful demonstration of indigenous data analysis and interpretation.

2. Institutional Strengthening and User Involvement (1980–1985)

Objective: To integrate remote sensing into national planning.

  • 1980: Aryabhata, India's first satellite (for science/technology), laid the foundation for satellite engineering.

  • 1983: Formation of the National Natural Resources Management System (NNRMS).

    • Purpose: Coordinate and integrate the use of remote sensing data with conventional data for national resource management.

    • Structure: Involved multiple user ministries (agriculture, water, forestry, etc.) and established Regional Remote Sensing Service Centres (RRSSCs).

    • Impact: Shift from experimental use to operational planning.

  • 1984: India began receiving data from LANDSAT and NOAA satellites through its own ground station in Shadnagar, Hyderabad — enhancing domestic data processing capabilities.

3. First-Generation Operational Satellites (1988–1995)

Objective: To launch and operate India's own Earth observation satellites.

  • 1988 (March 17): IRS-1A launched by the Soviet Union's Vostok launcher from Baikonur Cosmodrome.

    • Payload: LISS-I (72.5 m) and LISS-II (36.25 m) multispectral sensors.

    • Orbit: Sun-synchronous polar orbit.

    • Applications: Agriculture, forestry, water resource mapping, and soil studies.

    • Significance: Marked the beginning of the Indian Remote Sensing (IRS) series — India's first operational remote sensing satellite.

  • 1991 (August 29): IRS-1B launched — a near-identical successor with improved calibration and longer life.

    • Outcome: Data from IRS-1A/1B validated the national system for operational resource monitoring.

    • Impact: India achieved self-reliance in Earth observation for key resource sectors.

4. Second-Generation IRS Satellites (1995–2000)

Objective: To enhance spatial resolution and expand thematic applications.

  • 1995 (December 28): IRS-1C launched (from Baikonur).

    • Sensors:

      • PAN (5.8 m),

      • LISS-III (23.5 m),

      • WiFS (188 m).

    • Applications: Cartography, urban planning, and vegetation monitoring.

    • Significance: India entered the high-resolution mapping era.

  • 1997 (September 29): IRS-1D launched — similar to IRS-1C, providing stereo coverage and better radiometric accuracy.

  • 1998: Data from IRS-1C/1D began supporting international users, establishing India as a global remote sensing data provider.

5. Diversification and Specialized Missions (1999–2010)

Objective: To develop satellites tailored for thematic domains — oceans, cartography, and natural resources.

  • 1999 (May 26): IRS-P4 (Oceansat-1) launched.

    • Payload: Ocean Colour Monitor (OCM) and Multi-frequency Scanning Microwave Radiometer (MSMR).

    • Use: Ocean productivity, fisheries, and climate studies.

  • 2001 (May 5): IRS-P6 (Resourcesat-1) launched.

    • Sensors: LISS-III, LISS-IV, and AWiFS.

    • Purpose: Detailed agricultural and natural resource management.

  • 2005 (May 5): IRS-P5 (Cartosat-1) launched.

    • Payload: Two panchromatic cameras providing 2.5 m stereo imagery.

    • Applications: High-resolution cartography and digital elevation models (DEMs).

  • 2007 (October 23): Cartosat-2 launched — sub-meter resolution imagery.

    • Use: Urban planning, infrastructure, and defense.

  • 2009 (September 23): Oceansat-2 launched — followed by the Megha-Tropiques and SARAL (joint missions for climate and ocean studies).

6. Modernization and Microwave Era (2011–Present)

Objective: Integration of optical and microwave sensors, enhanced revisit times, and global data distribution.

  • 2013 (April 28): Resourcesat-2 launched — continuation of Resourcesat-1 with improved radiometry.

  • 2016 (March 10): Cartosat-2C launched — 0.65 m resolution; supported Smart City and infrastructure projects.

  • 2018 (March 12): Cartosat-2F launched, maintaining high-resolution optical imaging continuity.

  • 2019 (December 11): RISAT-2BR1 launched — radar imaging satellite with all-weather day-night capability.

    • Microwave sensors: Enabled mapping even under cloud cover, marking India's operational SAR (Synthetic Aperture Radar) era.

  • 2020–2023:

    • Launch of EOS (Earth Observation Satellite) series — replacing IRS nomenclature.

    • Satellites: EOS-01 (RISAT-type), EOS-04 (Radar), EOS-06 (Oceansat-3).

    • Integration of optical, microwave, and hyperspectral imaging systems.

7. Current Framework and Data Access (2020s–Present)

Objective: Streamline commercial and data dissemination processes.

  • 2020: Formation of NewSpace India Limited (NSIL) — a commercial arm of ISRO, responsible for marketing remote sensing data globally.

  • 2021: Launch of Bhoonidhi (Bhuvan-NIDHI) — ISRO's centralized data dissemination platform.

    • Provides access to IRS and EOS datasets for research, academia, and government users.

  • 2023–2025:

    • Integration with Digital India and Gati Shakti initiatives.

    • IRS data now forms the backbone of India's resource management, agriculture monitoring, climate resilience, and disaster response.

    • Over 15 active IRS/EOS satellites, making it the largest civilian remote sensing constellation globally.


PhaseYearsKey SatellitesMajor Achievements
Experimental1978–1981Bhaskara I & IIFirst Earth observation experiments
Institutionalization1983–1987NNRMS setupIntegration of users and ministries
First Generation1988–1991IRS-1A, 1BOperational remote sensing begins
Second Generation1995–2000IRS-1C, 1DHigh-resolution multispectral imaging
Specialized Missions1999–2010Oceansat, Cartosat, ResourcesatThematic data for various domains
Microwave & Modern Era2011–PresentRISAT, EOS seriesAll-weather, day-night, multi-sensor observation


Comments

Post a Comment

Popular posts from this blog

Radar Remote Sensing SAR

1. Radar and Radar Remote Sensing RADAR stands for Radio Detection and Ranging . It is an active remote sensing system that transmits microwave energy toward the Earth's surface and records the energy that is returned to the sensor as an echo or backscatter . Unlike passive optical remote sensing, radar does not depend on sunlight. Therefore, it can operate day and night and, at suitable wavelengths, can acquire data through clouds, haze and light rain. Hence, radar is widely described as an all-weather, day-and-night remote sensing technology . Basic principle Microwave pulse → transmission → interaction with surface → backscatter/echo → antenna receives signal → signal processing → radar image 2. Microwave Energy Radar systems use microwave electromagnetic radiation , generally in wavelength ranges from approximately 1 mm to 1 m . Important radar bands include: Band Approx. wavelength Common applications ...
Post a Comment
Read more

Atmospheric Window

The atmospheric window in remote sensing refers to specific wavelength ranges within the electromagnetic spectrum that can pass through the Earth's atmosphere relatively unimpeded. These windows are crucial for remote sensing applications because they allow us to observe the Earth's surface and atmosphere without significant interference from the atmosphere's constituents. Key facts and concepts about atmospheric windows: Visible and Near-Infrared (VNIR) window: This window encompasses wavelengths from approximately 0. 4 to 1. 0 micrometers. It is ideal for observing vegetation, water bodies, and land cover types. Shortwave Infrared (SWIR) window: This window covers wavelengths from approximately 1. 0 to 3. 0 micrometers. It is particularly useful for detecting minerals, water content, and vegetation health. Mid-Infrared (MIR) window: This window spans wavelengths from approximately 3. 0 to 8. 0 micrometers. It is valuable for identifying various materials, incl...
Post a Comment
Read more

Lidar

LiDAR (Light Detection and Ranging) is an active remote sensing technology that measures distances by illuminating a target with laser pulses and analyzing the time it takes for the reflected light to return. Unlike passive systems (e.g., cameras, multispectral sensors), LiDAR provides its own energy source (laser), allowing it to operate both day and night and even penetrate through vegetation canopies . 🔹 How LiDAR Works (Step-by-Step Process) Laser Pulse Emission The system emits rapid, short pulses of laser light (commonly in the near-infrared wavelength, 1064 nm ). Some systems emit up to hundreds of thousands of pulses per second . Interaction with Target Surface The laser beam strikes objects such as vegetation, buildings, or bare ground. Depending on the object's structure, part of the pulse may scatter or reflect. Return Signal Detection The sensor records multiple returns : First Return → typically vegetation canopy tops. ...
Post a Comment
Read more

Radar image. Polarization in Remote Sensing

L band radars operate on a wavelength of 15-30 cm and a frequency of 1-2 GHz. L band radars are mostly used for clear air turbulence studies. S band radars operate on a wavelength of 8-15 cm and a frequency of 2-4 GHz. Because of the wavelength and frequency, S band radars are not easily attenuated. . Polarization refers to the direction of travel of an electromagnetic wave vector's tip: vertical (up and down), horizontal (left to right), or  circular (rotating in a constant plane left or right). . a synthetic aperture radar (SAR) for high-resolution imaging. a radar altimeter, to measure the ocean topography. echo amplitude a wind scatterometer to measure wind speed and direction. Other types of radars have been flown for Earth observation missions: precipitation radars such as the  Tropical Rainfall Measuring Mission, or cloud radars like the one used on Cloudsat. . RISAT-1 (SAR, ISRO India, 2012) RORSAT (SAR, Soviet Union, 1967-1988) Seasat (SAR, altimeter, scatterometer, US, 19...
Post a Comment
Read more

Geometric Correction

When satellite or aerial images are captured, they often contain distortions (errors in shape, scale, or position) caused by many factors — like Earth's curvature, satellite motion, terrain height (relief), or the Earth's rotation . These distortions make the image not properly aligned with real-world coordinates (latitude and longitude). 👉 Geometric correction is the process of removing these distortions so that every pixel in the image correctly represents its location on the Earth's surface. After geometric correction, the image becomes geographically referenced and can be used with maps and GIS data. Types  1. Systematic Correction Systematic errors are predictable and can be modeled mathematically. They occur due to the geometry and movement of the satellite sensor or the Earth. Common systematic distortions: Scan skew – due to the motion of the sensor as it scans the Earth. Mirror velocity variation – scanning mirror moves at a va...
Post a Comment
Read more