極化雷達教程（搬運工）
來自加拿大自然資源https://www.nrcan.gc.ca/earth-sciences/geomatics/satellite-imagery-and-air-photos/satellite-imagery-and-products/educational-resources/tutorial-radar-polarimetry/9579，源網頁在線可讀。包括極化雷達應用，基本概念，分類。網頁一章一章點着麻煩，整合到一個word，鏈接：https://pan.baidu.com/s/1681EcXn9Coad-wOnYPl0_w 提取碼：61ib
Permission for Use
This educational material within these tutorials is provided as is and may be copied in any form and used for non-commercial purposes provided that the content of the original material is not altered and it is clearly indicated that the Canada Centre for Mapping and Earth Observation (formerly Canada Centre for Remote Sensing), Natural Resources Canada is the originator of this material.
Figure 1-1 The Electric Field vector has horizontal (green) and vertical (blue) components, which combine to yield the net Electric Field vector (red). The locus of the tip of the Electric Field vector is shown in brown, tracing one cycle of the waveform on a plane perpendicular to the propagation direction.
Figure 1-2: Polarization ellipse showing the orientation angle 
and ellipticity 
, which are a function of the semi-major and semi-minor axes, a and b
Figure 7-1: The H / α plane showing the model-based classes and their partitioning. A description of the classes (Z1 - Z9) is given in the text.
The bounds shown in Figure 7-1 (Curve I and Curve II) show that when the entropy is high, the ability to classify different scattering mechanisms is very limited. An initial partition into nine classes (eight usable) has been suggested by Cloude and Pottier , and is shown in Figure 7-1. Classes are chosen based on general properties of the scattering mechanism and do not depend up on a particular data set. This allows an unsupervised classification based on physical properties of the signal. The class interpretations suggested by Cloude and Pottier are as follows (see for more details):
- Class Z1: Double bounce scattering in a high entropy environment
- Class Z2: Multiple scattering in a high entropy environment (e.g. forest canopy)
- Class Z3: Surface scattering in a high entropy environment (not a feasible region in H / α space)
- Class Z4: Medium entropy multiple scattering
- Class Z5: Medium entropy vegetation (dipole) scattering
- Class Z6: Medium entropy surface scattering
- Class Z7: Low entropy multiple scattering (double or even bounce scattering)
- Class Z8: Low entropy dipole scattering (strongly correlated mechanisms with a large imbalance in amplitude between HH and VV)
- Class Z9: Low entropy surface scattering (e.g. Bragg scatter and rough surfaces)