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About JERS-1

JERS-1 (Japanese Earth Resources Satellite) was an environmental Japanese satellite, also known as 'Fuyo-1', which launched on 11 February 1992 and ceased operations in October 1998. JERS-1 was a radar/optical mission and was developed by NASDA, the National Space Development Agency of Japan.

JERS-1 Mission Parameters
Orbit Height568km
Orbit TypeSun Synchronous
Repeat Cycle44 days

JERS-1 Objectives

The overall objectives of JERS-1 were the generation of global data sets with SAR and OPS sensors aimed at surveying resources, establishing an integrated Earth observation system, verifying instrument/system performances. The mission applications focused on survey of geological phenomena, land usage, observation of coastal regions, geologic maps, environment, disaster monitoring and demonstration of two-pass SAR interferometry for change detection.

JERS-1 Instruments

Synthetic Aperture Radar (SAR)

JERS-1 carried an early example of a SAR instrument. It was an L-band (HH polarisation) synthetic aperture radar.

Performance parameters of the JERS-1/SAR instrument
Center Frequency1.275 GHz (L-band, 23.5 cm wavelength)
Bandwidth15 MHz
Spatial Resolution18 m (range) x 18 m (azimuth, 3 looks)
Swath Width175 km
Transmitting Power35 µs
PRF (Pulse Repetition Frequency)1505.8 - 1606.0 Hz
Look angle
Antenna gain
Signal to ambiguity ratio
Array of 1024 microstrip radiation elements
>33.5 dB
>14 dB
Data Quantization3 bits
Data Rate3 Mbit/s


Optical Sensor (OPS)

This was a nadir-pointing multi-spectral imager.

Specification of OPS Spectral Bands
Band NoSpectral RangeGeneral Application
10.52 - 0.60 µm VIS (green)Vegetation surveys, land use, water monitoring
20.63 - 0.69 µm VIS (red)Chlorophyll absorption for vegetation differentiation
30.76 - 0.86 µm NIRBiomass surveys (nadir viewing)
40.76 - 0.86 µm NIRBiomass surveys (forward looking, at 15.3º to give stereo coverage with band 3)
51.60 - 1.71 µm (SWIR)Vegetation moisture
62.01 - 2.12 µm (SWIR)Hydrothermal mapping (eg. soils; geology)
72.13 - 2.25 µm (SWIR)Hydrothermal mapping (eg. soils; geology)
82.27 - 2.40 µm (SWIR)Hydrothermal mapping (eg. soils; geology)


Non-scientific measuring instrument

AVNIR: Side-looking optical camera.

JERS-1 Data


ESA offers to registered user the access through the Online Dissemination server to the following data collections:


The SAR Precision Image product is a multi-look (speckle-reduced), ground range, system corrected image. The product is calibrated and corrected for the SAR antenna pattern and range-spreading loss: radar backscatter can be derived from the product for geophysical modelling, but no correction is applied for terrain-induced radiometric effects. The image is not geocoded and terrain distortion (foreshortening and layover) has not been removed.



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