基于MODIS数据的雪深反演——以天山北坡经济带为例

应用中分辨率成像光谱仪(MODIS)数据进行雪深遥感反演理论和方法的研究。利用全波段地物光谱仪对不 同深度的积雪进行反射光谱值野外量测且同步测定雪深,通过分析雪深和反射光谱值的关系确定反演雪深的 MODIS最佳观测通道,应用新疆地区冬季MODIS 1B数据,以天山北坡经济带为实验区,结合该区域同期气象台 地面雪深观测记录数据建立雪深遥感反演数学公式。雪深反演结果与实测值对比表明,应用MODIS数据进行大 区域雪深反演时,其结果具有分辨率高、监测范围广的特点,可以清楚反映积雪覆盖范围和雪深空间分布特征,对 地表径流量计算、农业开发等具有应用价值。

Investigation on reflection spectr a of chirped and phase-shifted fiber Bragg gratings

The characteristics of chirped and phase-shifted fiber Bragg gratings have been investigated by the use of transfer matrix formulation. While the characteristics of a chirped and phase-shifted fiber Bragg grating are the same as those of non-chirped one in some important aspects, both the reflection and transmission windows of a chirped and phase-shifted fiber Bragg grating can be broadened in a wide range. Therefore, chirped and phase-shifted fiber Bragg gratings will have appScations in WDM or DWDM optical communication systems. The work in this paper can be used to design the new devices based on chirped and phase-shifted fiber Bragg gratings.