SCC Documentation: comparison docs/depolarization/depolarization.rst

-:e33ec332b498
+:32068c9ff7c7
 For what it concerns the method c) it, basically, requires to solve the equation:
 .. math::
 \alpha_s P_s + \alpha_p P_p = P
-in two different of atmospheric layers with considerably different *VLDR*. So to calibrate in this way the implementation of automatic layer identification in the SCC is required. As at moment this feature is not yet available within the SCC **ONLY** the method b) is considered.
+in two different atmospheric layers with considerably different *VLDR*. So to calibrate in this way the implementation of automatic layer identification in the SCC is required. As at moment this feature is not yet available within the SCC **ONLY** the method b) is considered.
 1.3 SCC procedure to calculate the PLDRP
 ----------------------------------------
 According to what mentioned before the SCC calculates the *PLDR* through the following steps:
 Let's suppose, for example, we have the perpendicular polarized lidar signal on the transmitted channel and the parallel polarized on reflected channel. For an ideal system (no diattenuation and cross-talk) we have:
 .. math::
 G_T=1 , \qquad H_T=-1, \qquad G_R=1, \qquad H_R=1
-If, on the other hands, we have the perpendicular polarized lidar signal on reflected channel and the total polarized on the transmitted for and ideal system we have:
+If, on the other hand, we have the perpendicular polarized lidar signal on reflected channel and the total polarized on the transmitted for and ideal system we have:
 .. math::
-G_T=1 , \qquad H_T=0, \qquad G_R=1, \qquad H_R=-1
+G_T=1 , \qquad H_T=1, \qquad G_R=1, \qquad H_R=-1
 **Table 1.1:** Polarization cross-talk correction parameters for ideal systems
 +----------------------+-----------------------------+-----------------+-----------------+-----------------+
 +                      +-----------------------------+-----------------+-----------------+-----------------+
 |                      | :math:`G_T`                 | :math:`H_T`     | :math:`G_R`     | :math:`H_R`     |
 +----------------------+-----------------------------+-----------------+-----------------+-----------------+
 | total                | 1                           | 0               | 1               | 0               |
 +----------------------+-----------------------------+-----------------+-----------------+-----------------+
-| parallel             | 1                           | 1               | 1               | 1               |
+| parallel             | 1                           | 1               | 1               | -1              |
 +----------------------+-----------------------------+-----------------+-----------------+-----------------+
-| cross                | 1                           | -1              | 1               | -1              |
+| cross                | 1                           | -1              | 1               | +1              |
 +----------------------+-----------------------------+-----------------+-----------------+-----------------+
 The *apparent calibration factor* (:math:`\eta^*`), *the calibration factor correction* (*K*) and the *polarization cross-talk correction parameters* are stored by **ELPP** module in the intermediate NetCDF files using the following variables:
 - :code:`Polarization_Channel_Gain_Factor` (*apparent calibration factor* - :math:`\eta^*` )
 :code:`32` :math:`\rightarrow` :code:`-45elPRnr`
 :code:`33` :math:`\rightarrow` :code:`-45elPRfr`
-.. warning:: It this variable is found in the SCC input file the corresponding settings in the SCC database will be **OVERWRITTEN**. Unless you don't have any valid reason to overwrite the database value this variable should not be used.
+.. warning:: This variable is found in the SCC input file the corresponding settings in the SCC database will be **OVERWRITTEN**. Unless you don't have any valid reason to overwrite the database value this variable should not be used.
 3. The variables:
 ::
 :scale: 100 %
 :align: center
 **Figure 3.1**: How to select signal types
-The first modification concerns the settings of the channel type for the 532 cross and 532 parallel polarization channels. Starting from SCC v4.0 polarization channels are identified as transmitted and reflected polarization channels and not on the base of their polarization state. So suppose if we suppose the cross polarized channel is transmitted by a polarizer beam splitter cube and the parallel is reflected the value reported in table 3.1 should be modified as they appear in table 3.2. So using the SCC web interface, the signal type of the 532 cross channel should be changed from :code:`elCP` to :code:`elPT` and in the same way the 532 parallel channel should be changed from :code:`elPP` to :code:`elPR` (see figure 3.1).
+The first modification concerns the settings of the channel type for the 532 cross and 532 parallel polarization channels. Starting from SCC v4.0 polarization channels are identified as transmitted and reflected polarization channels and not on the base of their polarization state. So if we suppose that the cross polarized channel is transmitted by a polarizer beam splitter cube, and the parallel is reflected, the value reported in table 3.1 should be modified as they appear in table 3.2. So using the SCC web interface, the signal type of the 532 cross channel should be changed from :code:`elCP` to :code:`elPT` and in the same way the 532 parallel channel should be changed from :code:`elPP` to :code:`elPR` (see figure 3.1).
 **Table 3.2:** The same of table 3.1 but with new channel types
 introduced in SCC v4.0
 +----------------+--------------+----------------+-------------+-----------+
 :code:`Raw_Lidar_Data[2][2][points]` :math:`\rightarrow` 3\ :sup:`rd` measured transmitted signal at -45 degrees
 :code:`Raw_Lidar_Data[2][3][points]` :math:`\rightarrow` 3\ :sup:`rd` measured transmitted signal at -45 degrees
-Once this file has been created it needs to be submitted to the SCC and linked to the configuration “depol\_calibration”. The result of the SCC analysis on this file will be the calculation of the calibration constant h\ :sup:`\*` that will be logged into the SCC database and can be used to calibrate Raman/Elastic backscat ter products (see section 3.3).
+Once this file has been created it needs to be submitted to the SCC and linked to the configuration “depol\_calibration”. The result of the SCC analysis on this file will be the calculation of the calibration constant h\ :sup:`\*` that will be logged into the SCC database and can be used to calibrate Raman/Elastic backscatter products (see section 3.3).
 3.3 Definition of “Raman/Elastic backscatter and linear depolarization ratio”
 -----------------------------------------------------------------------------
 In order to calculate the *PLDR* we need to modify the polarization related products linked to the “standard” measurement configurations (the configuration called “nighttime” and/or “daytime” in table 3.2).
 | Elastic backscatter   | 7            | Elastic backscatter   | x           | x         |
 |                       |              |                       |             |           |
 | 1064nm                |              |                       |             |           |
 +-----------------------+--------------+-----------------------+-------------+-----------+
-Product ID=1, 2, 4, 5, 7 do not need any modification as they do not involve polarization channels. The only product that need to be modified are the Product ID=3 and 6. To produce b532 files containing also *PLDR* we need to modify the “nighttime” and “daytime” configurations to include a product of type “Raman bakscatter and linear depolarization ratio” or “Elastic bakscatter and linear depolarization ratio” respectively. So the configuration reported in table 3.4 should be
+Product ID=1, 2, 4, 5, 7 do not need any modification as they do not involve polarization channels. The only product that need to be modified are the Product ID=3 and 6. To produce b532 files containing also *PLDR* we need to modify the “nighttime” and “daytime” configurations to include a product of type “Raman backscatter and linear depolarization ratio” or “Elastic bakscatter and linear depolarization ratio” respectively. So the configuration reported in table 3.4 should be
 changed to match what is included in table 3.5.
 **Table 3.5:** The same of table 3.4 but with new product types introduced in SCC v4.0
 +-----------------------+--------------+-----------------------------------------------------------+-------------+-----------+
 :scale: 100 %
 :align: center
 **Figure 3.4:** How to link a product to calibrate with a calibration product.
-.. warning:: Please not that also *Raman/Elastic backscatter products* need to be linked to a calibration product because the calibration constant and the corresponding correction factor is needed to calculate the total signal out of the two polarization components even if the *PLDR* is not involved in the product calculation.
+.. warning:: Please note that also *Raman/Elastic backscatter products* need to be linked to a calibration product because the calibration constant and the corresponding correction factor is needed to calculate the total signal out of the two polarization components even if the *PLDR* is not involved in the product calculation.

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comparison: docs/depolarization/depolarization.rst

docs/depolarization/depolarization.rst