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我们已经研究了从空间测量冠层热点ＢＲＤＦ的几个构想，其中最具前景的研究有主动光照和分置探测，以上二法可以从空间用探照灯模式进行热点的角度分布测量。构想中包含了一个可定向的光照源，如工作在大气窗波长的激光器，和一些固定在光源周围的高空间分辨率的探测器，用来接收几乎和原路反射方向同轴的光子。卫星微波控制和指令将允许激光定向和探测器聚焦，使整个系统象一个具有近于无限定向能力的探照灯一样工作。我们称这种构想中的卫星为热点探照卫星（ＨＳＳＬ）。卫星的标准高度为６００ｋｍ，这将可以测量热点ＢＲＤＦ达到１８度的相位角。分布的探测器可测量热点角度分布的强度方面，而无需复杂的成象探测器。为提高信噪比，系统可在夜间工作。这样，热点角度特征就能被量化和参数化得足够细，也就可以提取植被结构和生物物理信息。
We have studied several concepts for measuring canopy hotspots BRDF from space, of which the most promising ones are active illumination and fractional exploration, and the above two methods measure the hotspot angular distribution from the space searchlight mode. The concept includes an orientable source of illumination, such as a laser operating at the atmospheric window wavelength, and detectors of high spatial resolution fixed around the light source to receive photons that are nearly coaxial with the original reflection direction. Satellite microwave control and instructions will allow laser orientation and detector focus, allowing the entire system to behave like a searchlight with near-infinite directional capabilities. We call this concept satellite a hot search satellite (HSSL). The standard height of the satellite is 600 km, which will measure the phase angle at which the hot spot BRDF reaches 18 degrees. The distributed detector measures the intensity of the hot spot angular distribution without the need for a complex imaging detector. To improve signal-to-noise ratio, the system can work at night. In this way, hot-spot features can be quantified and parameterized sufficiently fine to extract vegetation structure and biophysical information.