Microwave RS Application and It_s Use in Vietnam

8/2/2019 Microwave RS Application and It_s Use in Vietnam

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Microwave remote sensing

applications and it’s use in

Vietnam

1. The applications of microwave RemoteSensing;

2. The Use of Microwave data in Vietnam



SAR applications

SAR interferometry for DEM generation;

SAR interferometry for subsident monitoring;

SAR for soil moisture content; SAR for biomass estimation;

SAR for crop estimation;

SAR for flood control; SAR for oil spills monitoring.



SAR for DEM generation

Two technology can be applied to generate DEM(Stereo SAR and Interferometric SAR);

Stereo SAR uses the parallax of SAR pair to

generate DEM; Interferometric SAR uses the deferent phases of

two SAR images to estimate the surface height;

The arrived DEM accuracy is very from 10 ms to50 m;

A DEM for a large area can be generated without

need of ground control or a few control points.



SAR interferometry for subsidence

monitoring

DiInSAR technology is used;

The millimeters level of accuracy can be

obtained.

This technology is good for monitoring the

construction site such as mining area, city...

It can help in predicting the hazards such as

mining exploitation.



SAR application for soil moisture

content estimation

Soil dielectric constant is calculatedthrough the SAR backscattering signals;

The soil moisture content can beestimated by the soil dielectric constant;

The accuracy of the estimated resultdepend on the SAR wave length, the

polarization used;

It is useful for irrigation monitoring as wellas the environmental monitoring.



SAR for biomass estimation

Combine two separate SAR technologies, SARpolarimetry and Interferometry;

SAR polarimetry uses the polarization state of receiving and transmitting channel to measure the

differences in backscatter due to orientation, shapeand material composition;

SAR interferometry coherently combines signalsfrom two separated spatial positions to extract the

interferogram; By combining two technologies, the vegetation

propertied such as vegetation height and biomasscan be determined.



SAR for crop estimation

Multi-temporal SAR data should be used to

monitor the plant grow and estimate the plant’s

biomass. The damages area due to Flooding or Sea

Serge... can also be monitoring;

The crop producing model may be used tosimulate the plant grow and predict the crop

yields;



SAR for flood control

SAR data is weather independent;

It can be obtain in before, during, and after the

flood event;

The flood area can be mapped;

The flood movement can be delineated;

The flood effect area can be mapped.



SAR for oil spills monitoring

The SAR data is cloud independent;

Oil cover surface is clearly displaced in SAR

images as dark regions; Some software can detect oil spills

automatically’

The thickness of the oil layer may also beobtained using SAR data;

With the multi-temporal data available, thesource of pollution may be discovered.



The Use of SAR data in Vietnam

Up to now, SAR data has not widely used in

Vietnam despite its various applications;

Most of the SAR data is used for the research

purposed;

Some projects have used the SAR data

namely: Flood control in Mekong delta river;Rice yield prediction in the Mekong river

delta;



Some reasons for the limit used of

SAR DATA in Vietnam

Lack of SAR data availability;

Microwave remote sensing was not taught in

the university;

SAR images is not easy to interpretation;

Lack of professional technician;

Lack of expert in this field of study;



In the future

With the data receiving station, the ASAR datawill be available;

The availability of ASAR data will encouragesthe user;

Hopefully, JAXA can help to increase the usedof SAR data by providing Remote SensingCentre with technical supports or ALOS-

PALSAR data in some research activities;

Thanks you!!!

Documents

Microwave RS Application and It_s Use in Vietnam