黑河综合遥感联合试验：扁都口-临泽飞行区L&K波段机载微波辐射计数据集（2008年7月4日）

本数据集为L&K波段机载微波辐射计于2008年07月04日获取，地点在扁都口-临泽飞行区。
其中L波段频率为1.4GHz，后视35度观测，获取双极化（H和V）信息；K波段频率为18.7GHz，天顶角观测，无极化信息。飞机9:48（北京时间，下同）从张掖机场起飞，14:14降落。10:16-11:40在扁都口摄区观测，飞行高度3100-3500m，飞行速度230-250km/hr左右。12:16-12:18低飞临泽水库1-6线，相对高度100m，飞行速度190km/hr。12:26-13:42在临泽摄区工作，飞行高度2000m左右，飞行速度250km/hr左右。13:49-13:51再次低飞临泽水库1-6线。
原始数据分为两部分，分别为微波辐射计数据和GPS数据。其中微波辐射计L和K波段均属非成像观测，由文本文件记录瞬时观测获得的数码值，GPS数据记录飞行时的经纬度以及飞机姿态参数等。使用微波辐射计观测数据时需要根据定标系数将记录的数码值转换为亮温值（定标系数文件与原始观测数据归档在一起）。同时，通过微波辐射计和GPS各自的时钟记录，可以将微波观测与GPS记录联系起来，给微波观测匹配地理坐标信息。由于微波辐射计观测分辨率较粗，数据处理中一般忽略飞机的航偏、翻滚以及俯仰效应。根据使用目标及飞行相对航高（H），在定标和坐标匹配后，还可以将观测信息栅格化，L和K波段的分辨率（x）与观测足迹（footprint）可以认为一致，参考分辨率为：L波段，x=0.3H；K波段，x=0.24H。经过以上各步处理后，可以获得用户能够直接使用的产品。

This dataset was acquired by an L&K band airborne microwave radiometer on July 4, 2008, over the Biandukou-Linze flight area.

The L-band operates at 1.4 GHz, conducts observations at a 35-degree backward-looking angle, and collects dual-polarization (H and V) information; the K-band operates at 18.7 GHz, performs zenith-angle observations without polarization information. The aircraft took off from Zhangye Airport at 09:48 (Beijing Time, the same below) and landed at 14:14. Observations were conducted over the Biandukou survey area from 10:16 to 11:40, with flight altitude ranging from 3100 to 3500 m and flight speed approximately 230–250 km/hr. From 12:16 to 12:18, the aircraft conducted a low-altitude flight over Linze Reservoir lines 1–6, with a relative altitude of 100 m and flight speed of 190 km/hr. From 12:26 to 13:42, operations were carried out over the Linze survey area, with flight altitude around 2000 m and flight speed approximately 250 km/hr. The aircraft flew over Linze Reservoir lines 1–6 again at low altitude from 13:49 to 13:51.

The raw data is divided into two parts: microwave radiometer data and GPS data. Both L-band and K-band microwave radiometer data are non-imaging observations, where the instantaneous observed digital values are recorded in text files. The GPS data records the flight's latitude and longitude, aircraft attitude parameters, and other relevant information. When using the microwave radiometer observation data, the recorded digital values need to be converted to brightness temperature values using calibration coefficients, and the calibration coefficient files are archived together with the original observation data. Meanwhile, the clock records of the microwave radiometer and GPS can be used to associate microwave observations with GPS records, enabling the matching of geographic coordinates to microwave observations.

Due to the relatively coarse resolution of microwave radiometer observations, the effects of aircraft yaw, roll, and pitch are generally ignored during data processing. Based on the usage objectives and the relative flight altitude (H), after calibration and coordinate matching, the observation information can also be rasterized. The resolution (x) of the L and K bands is considered consistent with their respective observation footprints, with the reference resolutions: L-band, x=0.3H; K-band, x=0.24H. After completing the above processing steps, products that can be directly used by users can be obtained.