Current Browsing: Remote Sensing Technology


HiWATER: Airborne CCD image data production in the sample strip in the upstream of the Heihe River Basin

On 25 August 2012, a RCD30 camera of Leica Company boarded on the Y-12 aircraft was utilized to obtain the optical remote sensing data. RCD30 camera has a focal length of 80 mm and four bands including red, green, blue and near-infrared bands. The absolute flight altitude is 5200 m and ground sample distance is 6-19 cm. The product includes TIF images and exterior orientation elements.

2019-09-11

WATER: Dataset of ground truth measurements for snow synchronizing with the airborne microwave radiometers (K&Ka bands) mission in the Binggou watershed foci experimental area on March 30, 2008

The dataset of ground truth measurements for snow synchronizing with the airborne microwave radiometers (K&Ka bands) mission was obtained in the Binggou watershed foci experimental area on Mar. 30, 2008. Those provide reliable data for retrieval of snow parameters and properties, especially for dry and wet snow identification. Observation items included: (1) Snow density, snow complex permittivity, snow volumetric moisture and snow gravimetric moisture by the snowfork in BG-A; (2) Snow parameters including snow depth, the snow surface temperature synchronizing with the airborne microwave radiometers (K&Ka bands), the snow layer temperature, the snow grain size and snow density in BG-A (10 points), BG-B (6 points), BG-F (12 points), BG-H (21 points) and BG-I (20 points); For each snow pit, the snowpack was divided into several layers with 10-cm intervals of snow depth. The layer depth (by the ruler), the snow grain size (by the handheld microscope), snow density (by the cutting ring) and the snow temperature (by the probe thermometer) were obtained at each snow pit. Two files including raw data and the preprocessed data were archived.

2019-09-10

WATER: Dataset of airborne microwave radiometers (L&K bands) mission in the Linze-Biandukou flight zone on May 25 2008

This dataset was acquired on May 25, 2008 by the L&K-band airborne microwave radiometer at the Linze-Biandukou flight area.The L-band frequency is 1.4 GHz, the rear view is 35 degrees, and the dual-polarization (H and V) information is obtained; the K-band frequency is 18.7 GHz, with zenith angle observation, and there is no polarization information. The plane took off from Zhangye Airport at 9:51 (Beijing time, the same below) and landed at 15:01. The observation from 10:10 to 12:30 was in the Linze area, the flight altitude is about 1800m, and the flight speed is about 250km/hr. The plane flew low over Linze Reservoir from 12:31 to 12:38. The plane works in the Bianduko aerophotography region from13:13 to 14:35, the flight altitude is about 3000m, and the flight speed is about 250km/hr. The original data is divided into two parts: microwave radiometer data and GPS data. The L and K bands of microwave radiometer are all from non-imaging observation, the digital values obtained from instantaneous observation are recorded by text files, the longitude and latitude of flight and the attitude parameters of aircraft are recorded by GPS data. At the same time, through the respective clock records of the microwave radiometer and GPS, the microwave observation can be linked with the GPS record, and the microwave observation can be matched with the geographical coordinate information. Due to the relatively low resolution of the microwave radiometer, the leeway, welter and pitching of the aircraft are generally neglected in data processing. According to the target of use and relative flight altitude (H), after calibration and coordinate matching, the observation information can be rasterized. The resolution (x) of the L and K bands can be considered consistent with the observation footprint. The reference resolution is: L band, x = 0.3H; K band, x = 0.24H. After the above steps, products that can be directly used by users can be obtained.

2019-07-20

WATER: Dataset of 3D scanning of forest structure using the ground-based LiDAR at the super site around the Dayekou Guantan forest station

This data set is the acquisition of the super-site forest 3D structure of the scanning point cloud data and other ancillary data based on the ground-based lidar (LiDAR) . Data acquisition time is from June 4, 2008 to June 12, 2008. Riegl LMS-Z360i ground-based LiDAR was used. The super site is divided into 16 sub-samples of 25m×25m, LiDAR base station points are set in each sub-sample, and LiDAR acquisition 3D full coverage LiDAR point metadata is set at each base station point. The content of the data set: total station measurement coordinates (x, y, z) for each LiDAR data acquisition base station point, the instrument attitude measured by a digital slope meter and an angle meter when each station collects data, and the laser radar scanning point cloud data at each station. This data set can provide realistic 3D forest scenes, provide detailed ground observation data for the development and correction of various 3D forest remote sensing models, and provide ground verification data for airborne and spaceborne remote sensing data.

2019-07-16

HiWATER: Dataset of airborne microwave radiometers (L bands) mission in the middle reaches of the Heihe River Basin on 10 July, 2012

The dataset of airborne Polarimetric L-band Multibeam Radiometers (PLMR) was acquired on 10 July, 2012, located in the middle reaches of the Heihe River Basin. The aircraft took off at 10:30 am (UTC+8) from Zhangye airport and landed at 15:30 pm, with the flight time of 5 hours. The flight was performed in the altitude of about 2500 m and at the speed of about 220-250 km during the observation, corresponding to an expected ground resolution of about 750 m. The PLMR instrument flown on a small aircraft operates at 1.413 GHz (L-band), with both H- and V-polarizations at incidence angles of ±7.5°, ±21.5° and ±38.5°. PLMR ‘warm’ and ‘cold’ calibrations were performed before and after each flight. The processed PLMR data include 2 DAT files (v-pol and h-pol separately) and 1 KMZ file for each flying day. The DAT file contains all the TB values together with their corresponding beam ID, incidence angle, location, time stamp (in UTC) and other flight attitude information as per headings. The KMZ file shows the gridded 1-km TB values corrected to 38.5 degrees together with flight lines. Cautions should be taken when using these data, as the RFI contaminations are often higher than expected at v-polarization.

2019-05-23

HiWATER: Airborne CCD image data in the Shenshawo desert area of the Heihe River Basin

On 19 August 2012, a RCD30 camera of Leica Company boarded on the Y-12 aircraft was used to obtain the CCD image. RCD30 camera has a focal length of 80 mm and four bands including red, green, blue and near-infrared bands. The absolute flight altitude is 2900 m and ground sample distance is 10 cm. The data includes TIF images and exterior orientation elements.

2019-05-23

HiWATER: Airborne CCD image data in Hulugou Catchment

On 25 August and 28 August, 2012, a RCD30 camera of Leica Company boarded on the Y-12 aircraft was used to obtain CCD image. RCD30 camera has a focal length of 80 mm and four bands including red, green, blue and near-infrared bands. The absolute flight altitude is 4800 and 5200 m, and ground sample distance is 6-19 cm. The product includes TIF images and exterior orientation elements.

2019-05-23

WATER: Dataset of airborne microwave radiometers (L&K bands) mission in the A'rou-Biandukou flight zone on Mar. 19, 2008

The dataset of airborne microwave radiometers (L&K) mission was obtained in the A'rou-Biandukou flight zone on Mar. 19, 2008. The frequency of L bands was 1.4 GHz with back sight of 35 degree and dual polarization (H&V) was acquired; and the frequency of K band was 18.7 GHz at the nadir view angle without polarization. The plane took off at Zhangye airport at 9:25 (BJT) and landed at 12:50 along the scheduled lines at the altitude about 4100m and speed about 260km/hr. The raw data include microwave radiometer (L&K bands) data and GPS data; the former are instantaneous non-imaging observation recorded in text, which will be converted into brightness temperatures according to the calibration coefficients (filed with raw data together), and the latter are aircraft longitude, latitude and attitude. Moreover, based on the respective real-time clock log, observations by the microwave radiometer and GPS can be integrated to offer coordinates matching for the former. Yaw, flip, and pitch motions of aircraft were ignored due to the low resolution of microwave radiometer observations. Observation information can also be rasterized, as required, after calibration and coordinates matching. L&K bands resolution (x) and footprint can be approximately estimated as x=0.3H (H is relative flight height) for L band and x=0.24H for K band.

2019-05-23

WATER: Dataset of ground truth measurements for snow synchronizing with EO-1 Hyperion in the Binggou watershed foci experimental area on Mar. 22, 2008

The dataset of ground truth measurements for snow synchronizing with EO-1 Hyperion was obtained in the Binggou watershed foci experimental area on Mar. 22, 2008. Those provide reliable data for retrieval of snow parameters from remote sensing approaches. Observation items included: (1) snow surface emissivity by the portable emissivity determinator near the Binggou cold region hydrometerological station; (2) snow density, snow complex permittivity, snow volumetric moisture and snow gravimetric moisture by the snowfork in BG-A from 11:20-13:53 (BJT) on Mar. 2, 2008; (3) snow parameters in BG-A, BG-B, BG-C, BG-D, BG-E and BG-F, and variables including the snow layer temperature by the probe thermometer, the snow grain size by the handheld microscope, snow density by the aluminum case and the snow surface temperature and the snow-soil interface temperature by the handheld infrared thermometer simultaneous with the satellite; (4) the land surface infrared temperature in BG-D, BG-E, BG-B and BG-F during the airborne mission; (5) fresh snow albedo by the total radiometer east to A2; (6) snow spectrum by the portable ASD from Xinjiang Meteorological Administration and Nanjing University, GPS recordings enclosed. Two files including raw data and preprocessed data were archived.

2019-05-23

WATER: Dataset of airborne microwave radiometers (L&K bands) mission in the Biandukou flight zone on Mar. 21, 2008

The dataset of airborne microwave radiometers (L&K) mission was obtained in the Biandukou flight zone on Mar. 21, 2008. The frequency of L bands was 1.4 GHz with back sight of 35 degree and dual polarization (H&V) was acquired; and the frequency of K band was 18.7 GHz at the nadir view angle without polarization. The plane took off at Zhangye airport at 8:00 (BJT) and landed at 11:40, from north to south along the scheduled lines at the altitude about 4100m (400m for the low flight) and speed about 290km/hr . The raw data include microwave radiometer (L&K) data and GPS data; the former were instantaneous non-imaging observation recorded in text, which could be converted into brightness temperatures according to the calibration coefficients (filed with raw data together), and the latter were aircraft longitude, latitude and attitude. Moreover, based on the respective real-time clock log, observations by the microwave radiometer and GPS can be integrated to offer coordinates matching for the former. Yaw, flip, and pitch motions of aircraft were ignored due to the low resolution of microwave radiometer observations. Observation information can also be rasterized, as required, after calibration and coordinates matching. L&K bands resolution (x) and footprint can be approximately estimated as x=0.3H (H is relative flight height) for L and x=0.24H for K.

2019-05-23