Current Browsing: Remote Sensing Technology


HiWATER: Dataset of emissivity of typical terrain over Heihe River Basin (2014.03.25-2015.06.30)

This data set is typical specific emissivity data set of Heihe River Basin. Data observation is from March 25, 2014 to June 30, 2015. Instrument: Portable Fourier transform infrared spectrometer (102f), hand-held infrared thermometer Measurement method: 102f was used to measure the radiation values of cold blackbody, warm blackbody, observation target and gold plate. Using the radiation value of the cold and warm blackbody, the 102f is calibrated to eliminate the influence of the instrument's own emission. By using the iterative inversion algorithm based on smoothness, the specific emissivity and the object temperature are inversed. The specific emissivity range is 8-14 μ m, and the resolution is 4cm-1. This data set contains the original radiation curves (in ASCII format) and recording files of cold blackbody, warm blackbody, measured target and gold plate obtained by 102f.

2020-03-13

WATER: Dataset of airborne microwave radiometers (L&K bands) mission in the Linze flight zone on Jul. 8, 2008

This data set was acquired by L & K band airborne microwave radiometer on July 8, 2008 in Linze flight area. The frequency of L-band is 1.4GHz, and the backsight is 35 degrees to obtain dual polarization (H and V) information; the frequency of K-band is 18.7ghz, and there is no polarization information. The plane took off from Zhangye airport at 10:00 (Beijing time, the same below) and landed at 13:38. 10: At 23-13:10, the flight altitude was about 1900m and the flight speed was about 230-250km / hr. Among them, 12:21-12:27 low flying Linze reservoir line 1-6 has a relative altitude of 100m and a flight speed of 190km / hr. 12: 56-13:08 low flying desert marking twice (line 1-7, first North to south, then south to North). The original data is divided into two parts: microwave radiometer data and GPS data. The L and K bands of microwave radiometer are non imaging observations. The digital values obtained from the instantaneous observation are recorded in the text file, and the longitude and latitude as well as the aircraft attitude parameters are recorded in the GPS data. When using microwave radiometer to observe data, it is necessary to convert the digital value recorded into the bright temperature value according to the calibration coefficient (the calibration coefficient file is filed with the original observation data). At the same time, through the clock records of microwave radiometer and GPS, we can connect the microwave observation with GPS record and match the geographic coordinate information for the microwave observation. Due to the coarse observation resolution of microwave radiometer, the effects of aircraft yaw, roll and pitch are generally ignored in data processing. According to the target and flight relative altitude (H), after calibration and coordinate matching, the observation information can also be gridded. The resolution (x) of L band and K band is consistent with that of observation footprint. The reference resolution is: L band, x = 0.3H; K band, x = 0.24h. After the above steps, we can get the products that users can use directly.

2020-03-10

WATER: Dataset of airborne microwave radiometers (K&Ka bands) mission in the Binggou watershed flight zone on Mar. 29, 2008

This data set was acquired by K & Ka band airborne microwave radiometer on March 29, 2008, in the Binggou watershed flight zone. Among them, K-band frequency is 18.7ghz, zenith angle observation, no polarization information; Ka band frequency is 36.0ghz, scanning imaging, scanning range ± 12 °, vertical polarization observation. The plane took off from Zhangye airport at 8:49 (Beijing time, the same below) and landed at 12:54. 9: At 25-12:08, 18 routes were flown according to the scheduled design, with a flight altitude of about 5000m and a flight speed of about 220-250km / hr. The original data is divided into two parts: microwave radiometer data and GPS data. The K-band of microwave radiometer belongs to non imaging observation, and the digital value obtained from instantaneous observation is recorded in the text file. Ka band belongs to imaging observation, which is different from L band and K band data. The original record of Ka band is hexadecimal text file. In data processing, the hexadecimal file needs to be converted to decimal system first, and then 112 data (the angle difference of each two data points is 24 / 112 = 0.214 degrees) are collected uniformly within the scanning range of 24 degrees. GPS data record the latitude and longitude of the flight and the aircraft attitude parameters. When using microwave radiometer to observe data, it is necessary to convert the digital value recorded into the bright temperature value according to the calibration coefficient (the calibration coefficient file is filed with the original observation data). At the same time, through the clock records of microwave radiometer and GPS, microwave observation and GPS record can be linked to match the geographical coordinate information for microwave observation. When processing Ka band data, the angle scanning effect should also be considered, and 112 data in the scanning period should be given geographical coordinate information respectively. Due to the coarse observation resolution of microwave radiometer, the effects of aircraft yaw, roll and pitch are generally ignored in data processing. According to the target and flight relative altitude (H), after calibration and coordinate matching, the observation information can also be gridded. The resolution (x) of K-band is consistent with that of observation footprint. The reference resolution is: x = 0.24h; the resolution of Ka band is 39m. After the above steps, we can get the products that users can use directly.

2020-03-09

WATER: Dataset of airborne microwave radiometers (L&K bands) mission in the Biandukou-Linze flight zone on Jul. 4, 2008

This data set was acquired by L & K band airborne microwave radiometer on July 4, 2008, in the Biandukou-Linze flight zone. The frequency of L-band is 1.4GHz, and the backsight is 35 degrees to obtain dual polarization (H and V) information; the frequency of K-band is 18.7ghz, and there is no polarization information. The plane took off from Zhangye airport at 9:48 (Beijing time, the same below) and landed at 14:14. 10: At 16-11:40, the flight altitude was 3100-3500m and the flight speed was about 230-250km / hr. 12: 16-12:18 low flying Linze reservoir line 1-6, relative altitude 100m, flight speed 190km / hr. 12: At 26-13:42, he worked in Linze photography area, with a flight altitude of about 2000m and a flight speed of about 250km / hr. 13: 49-13:51 fly low again to Linze reservoir line 1-6. The original data is divided into two parts: microwave radiometer data and GPS data. The L and K bands of microwave radiometer are non imaging observations. The digital values obtained from the instantaneous observation are recorded in the text file, and the longitude and latitude as well as the aircraft attitude parameters are recorded in the GPS data. When using microwave radiometer to observe data, it is necessary to convert the digital value recorded into the bright temperature value according to the calibration coefficient (the calibration coefficient file is filed with the original observation data). At the same time, through the clock records of microwave radiometer and GPS, we can connect the microwave observation with GPS record and match the geographic coordinate information for the microwave observation. Due to the coarse observation resolution of microwave radiometer, the effects of aircraft yaw, roll and pitch are generally ignored in data processing. According to the target and flight relative altitude (H), after calibration and coordinate matching, the observation information can also be gridded. The resolution (x) of L band and K band is consistent with that of observation footprint. The reference resolution is: L band, x = 0.3H; K band, x = 0.24h. After the above steps, we can get the products that users can use directly.

2020-03-09

WATER: Dataset of airborne microwave radiometers (L&K bands) mission in the A'rou flight zone in the morning of Apr. 1, 2008

This data set was acquired by the L & K band airborne microwave radiometer on the morning of April 1, 2008, in the A'rou flight zone. The frequency of L-band is 1.4GHz, and the backsight is 35 degrees to obtain dual polarization (H and V) information; the frequency of K-band is 18.7ghz, and there is no polarization information. The plane took off from Zhangye airport at 8:06 (Beijing time, the same below) and landed at 11:17. 8: 50-10:13 fly from north to south, observe and reserve 10 routes, flight height is about 4100m, flight speed is about 260km / hr. 10: At 20-10:35, Jiafei 6-8 and 6-9 lines completed the observation. The original data is divided into two parts: microwave radiometer data and GPS data. The L and K bands of microwave radiometer are non imaging observations. The digital values obtained from the instantaneous observation are recorded in the text file, and the longitude and latitude as well as the aircraft attitude parameters are recorded in the GPS data. When using microwave radiometer to observe data, it is necessary to convert the digital value recorded into the bright temperature value according to the calibration coefficient (the calibration coefficient file is filed with the original observation data). At the same time, through the clock records of microwave radiometer and GPS, we can connect the microwave observation with GPS record and match the geographic coordinate information for the microwave observation. Due to the coarse observation resolution of microwave radiometer, the effects of aircraft yaw, roll and pitch are generally ignored in data processing. According to the target and flight relative altitude (H), after calibration and coordinate matching, the observation information can also be gridded. The resolution (x) of L band and K band is consistent with that of observation footprint. The reference resolution is: L band, x = 0.3H; K band, x = 0.24h. After the above steps, we can get the products that users can use directly.

2020-03-09

Integrated remote sensing experiment of Heihe River: ENVISAT AATSR remote sensing data set

Advanced along orbit scanning radiometer (AATSR) is an advanced tracking scanning radiometer sensor mounted on the European Space Agency ENVISAT satellite. It is one of many high-precision and stable infrared radiometers for retrieving sea surface temperature (SST). Its accuracy can reach 0.3k, and it can also be used to record meteorological data. AATSR is a multi-channel imaging radiometer. Its main goal is to provide global ocean surface temperature with high accuracy and stability for monitoring the earth's climate change. At present, there are 38 ENVISAT AATSR images in Heihe River Basin. The acquisition time is 2008-05-17 (2 scenes), 2008-05-27 (2 scenes), 2008-05-30 (2 scenes), 2008-06-02 (2 scenes), 2008-06-12 (2 scenes), 2008-06-15 (2 scenes), 2008-06-18 (2 scenes), 2008-06-21 (2 scenes), 2008-07-04 (2 scenes), 2008-07-072008-07-102008-07-172008-07-202008-07-232008-07-262008-08-022008-08-052008-08-082008 -08-11,2008-08-14,2008-08-21,2008-08-24,2008-08-27,2008-08-30,2008-09-06,2008-09-12,2008-09-15,2008-09-18,2008-09-25。 The product level is L1B, which has been corrected by radiation but not by geometry. The ENVISAT AATSR remote sensing data set of Heihe comprehensive remote sensing joint test was obtained through the China EU "dragon plan" project (Project No.: 5322) (see the data use statement for details).

2020-03-09

Heihe integrated remote sensing joint experiment: ASTER Remote Sensing Data Set (2007-2008)

ASTER data in 2007 and 2008 are 15 scenes, covering the whole Heihe River Basin. Acquisition time: 2007-10-22 (1 scene), 2007-11-14 (1 scene), 2007-11-23 (1 scene), 2007-12-04 (1 scene), 2008-01-28 (1 scene), 2008-02-13 (1 scene), 2008-05-03 (4 scenes), 2008-05-05 (1 scene), 2008-05-17 (1 scene), 2008-06-04 (2 scenes), 2008-06-13 (1 scene). The product level is L1B, which has been calibrated by radiation and geometry. The ASTER Remote sensing data set of Heihe integrated remote sensing joint experiment was obtained from NASA's data website (https://wist.echo.nasa.gov/) through international cooperation.

2020-03-09

HiWATER: Dataset of ground truth measurements synchronizing with airborne PLMR mission in the Yingke oasis and Huazhaizi desert steppe on June 28-29, 2012

The first dataset of ground truth measurements synchronizing with airborne Polarimetric L-band Multibeam Radiometer (PLMR) mission was obtained in the Yingke oasis and Huazhaizi desert steppe on 28-29 June, 7, 10, 26 July, 2 August, 2012 (UTC+8). The dataset of ground truth measurements synchronizing with airborne Polarimetric L-band Multibeam Radiometer (PLMR) mission was obtained in the Linze Inland River Basin Comprehensive Research Station on 3 July, 2012. PLMR is a dual-polarization (H/V) airborne microwave radiometer with a frequency of 1.413 GHz, which can provide multi-angular observations with 6 beams at ±7º, ±21.5º and ±38.5º. The PLMR spatial resolution (beam spot size) is approximately 0.3 times the altitude, and the swath width is about twice the altitude. The measurements were conducted in the southwest part of the Zhangye Oasis, which included two sampling plots. One was located in Gobi desert with an area of 1 km × 1 km. Due to its homogeneous landscape, around 10 points were sampled to acquire the situation of soil water content. The other sampling plot was designed in farmlands with a dominant plant type of maize. Ground measurements took place along 16 transects, which were arranged parallelly with an interval of 160 m between each other in the east-west direction. In each 2.4 km long transect, soil moisture was sampled at every 80 m in the north-south direction. Steven Hydro probes were used to collect soil moisture and other measurements. For each sampling point in farmland, two measurements were acquired within an area of 1 m2, with one for the soil covered by plastic film (point name was tagged as LXPXXA) and the other for exposed soil (point name was tagged as LXPXXB). The field campaign started from 11:00 AM, but stopped at 4:00 PM on 28 June because of rain. The rest of measurements were completed from 10:30 AM to 5:30 PM on 29 June. Concurrently with soil moisture sampling, vegetation properties were measured at around 10 locations within the farmland sampling plot. Observation items included: Soil parameters: volumetric soil moisture (inherently converted from measured soil dielectric constant), soil temperature, soil dielectric constant, soil electric conductivity. Vegetation parameters: biomass, vegetation water content, canopy height. Data and data format: This dataset includes two parts of measurements, i.e. soil and vegetation parameters. The former is as shapefile, with measured items stored in its attribute table. The measured vegetation parameters are recorded in an Excel file.

2019-09-15

HiWATER: Dataset of airborne microwave radiometers (L bands) mission in the river way of the midstream of the Heihe River Basin on Jul. 4, 2012

The dataset of airborne Polarimetric L-band Multibeam Radiometers (PLMR) was acquired on 4 July, 2012, located along the riverway of Heihe River in the middle reaches of the Heihe River Basin. The aircraft took off at 10:50 am (UTC+8) from Zhangye airport and landed at 14:50 pm, with the flight time of 4 hours. The flight was performed in the altitude of about 1000 m and at the speed of about 220-250 km during the observation, corresponding to an expected ground resolution of about 300 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.

2019-09-15

HiWATER: Wide-angle Infrared Dual-mode line/area Array Scanner, WIDAS (26th, July, 2012)

On 26 July 2012, a Wide-angle Infrared Dual-mode line/area Array Scanner (WIDAS) carried by the Y-12 aircraft was used in a visible near Infrared thermal Dual-mode airborne remote sensing experiment, which is located in the artificial oasis eco-hydrology experimental area (5×5 km). WIDAS includes an CCD cameras with spatial resolution 0.2 m, a visible near Infrared multispectral camera with five bands scanner (an maximum observation angle 48° and spatial resolution 1 m), and a thermal image camera with spatial resolution 4.8 m. The CCD camera data are recorded in DN values processed by mosaic and orthorectification. The multispectral camera data are recorded in reflectance processed by atmospheric and geometric correction. Thermal image camera data are recorded in radiation brightness temperature processed by atmospheric and geometric correction.

2019-09-15