Instructions
Spectral fit information:
The power spectra of the pulse returns are fitted with a generalized Gaussian (gg) model. A gg equation is given as below:
$\left< S_v \right> = N + A_1 \exp^{-\frac{1}{2}\left| \frac{v-V_1}{S_1} \right|^{P_1}} + A_2 \exp^{-\frac{1}{2}\left| \frac{v-V_2}{S_2} \right|^{P_2}}$
- $N$: Noise floor
- $A$: Power magnitude
- $V$: Doppler shift (m/s)
- $S$: Doppler width (m/s)
- $P$: Shape parameter
- $1, 2$: preferred and secondary gg peaks
Tab information:
Click on the following Tabs on top-left to display time-height plots of fitted and/or derived data from Doppler spectral measurements conducted with four radar beams (use “Beam directions” and “Rad. patterns” buttons for radar beam information):
- SNR Map: Signal-to-Noise Ratio map plots
- LOS Map: Line-Of-Sight Doppler velocity map calculated with spectral fitting routine of Jen Smith.
- LOS_gg Map: Similar to LOS Map, using an improved spectral fitting algorithm gg (fit of a dual Generalized Gaussian model followed by a single Gaussian selection)
- LOS_gg SpcWidth Map: Spectral width map calculated by second central moment of the selected Doppler peaks.
- Jen's Wind Map: Derived (eastward, northward, upward) wind components using LOS Map data and Jen's algorithm to optimize the wind vectors calculation.
- Wind_gg Map: Similar to Jen's Wind Map but using LOS_gg Map data --- no additional algorithm was used to optimize the wind vectors calculation.
- Wind_gg+ Map: Similar to Wind_gg Map but using an additional DBSCAN clustering algorithm and bottom-to-top selection approach to optimize in utilizing
the correct spectral peak detected in dual Generalized Gaussian fit.
- Wind_gg Errors Map: Estimation uncertainties of the Wind_gg+ Map data.
The map presented in each Tab is an active Bokeh object that can be controlled as specified by the selected Bokeh action icons placed on the left of the plot areas (Pan, Box Zoom, Resize, Wheel Zoom, Reset). On each map you can zoom in (with click and drag action to select an area when Box Zoom icon is active) or select a time-height (with a single click) for spectral and fitted curve displays.
Fitted curves (Generalized Gaussians) can be superposed on the spectral curves plotted on the right as controlled by the following Buttons placed on top-right:
- jen fit OFF/ON: for toggling the display (or not) of jen's fit superposed (dashed red = showing both Gaussians) on the measured spectrum (blue plot).
- gg fit ON/OFF: for toggling the display (or not) of gg fits (thick blue = first preferred Gaussian / thick red = second Gaussian).
- gg_test fit: click to display gg test fits (thin blue = first preferred Gaussian / thin red = second Gaussian).
- refresh: click this button for refreshing the displayed fits after using any of the three buttons above.
Re-clicking on new positions on the map will show the measured and fitted spectra selected in the previous step at new time-height points.
The cluster plot demonstrates how DBSCAN algorithm is used to separate mainbeam Doppler velocities from sidebeam Doppler velocities. The plot consists of three columnns of Doppler velocities vs time scatter plots with each row representing a range gate. The left column shows the scatter plots before DBSCAN is applied where blue dots indicate mainbeam Doppler velocities, and red dots indicate sidebeam Doppler velocities. The middle column lists the scatter plots with multiple clusters detected by DBSCAN, each cluster being represented by different colors (Indigo color indicates noise). The right column represents the scatter plots with corrected blue mainbeam dots and red sidebeam dots by using clusters from a previous range gate and a current range gate.
- Cluster Plot: select a channel from a dropdown menu, which shows Doppler velocity vs time scatter plots before and after DBSCAN algorithm of the corresponding channel.
Additional buttons:
- Beam directions: click to view the azimuth and elevation (from zenith) of each beam.
- Rad. patterns: click to view the mainlobe and sidelobe of each beam.
- Edit files: edit fitting algorithm files (password protected feature)
Mainbeam $\Theta_x$, $\Theta_y$ information:
This table displays the directional cosines x and y of the mainbeams for all channels.
| Date |
Ch 0 ($\Theta_x$, $\Theta_y$) |
Ch 1 ($\Theta_x$, $\Theta_y$) |
Ch 2 ($\Theta_x$, $\Theta_y$) |
Ch 3 ($\Theta_x$, $\Theta_y$) |
| Jan - Dec 2016 |
0.0204, 0.0545 |
-0.0603, -0.0406 |
0.0397, -0.0412 |
-0.0027, 0.0226 |
Jan - Dec 2015 |
0.0204, 0.0545 |
-0.0603, -0.0406 |
0.0397, -0.0412 |
-0.0027, 0.0226 |
| Jun - Dec 2014 |
0.0204, 0.0545 |
-0.0603, -0.0406 |
0.0397, -0.0412 |
-0.0027, 0.0226 |
| Feb - May 2014 |
0.0171, 0.0556 |
-0.0603, -0.0406 |
0.0397, -0.0412 |
-0.0032, 0.0276 |
| Jan 2014 |
0.0126, 0.0561 |
-0.0591, -0.0275 |
0.0404, -0.0408 |
-0.0034, 0.0276 |
| Jan - Dec 2009 |
0.0126, 0.0561 |
-0.0580, -0.0284 |
0.0404, -0.0408 |
-0.0331, 0.0556 |
| Jan - Dec 2007 |
0.0305, 0.0563 |
-0.0289, -0.0066 |
0.0289, -0.0066 |
-0.0304, 0.0563 |
| Jan - Dec 2006 |
0.0305, 0.0563 |
-0.0289, -0.0066 |
0.0289, -0.0066 |
-0.0304, 0.0563 |
| Apr - Dec 2005 |
0.0305, 0.0563 |
-0.0289, -0.0066 |
0.0289, -0.0066 |
-0.0304, 0.0563 |
| Jan - Mar 2005 |
0.0305, 0.0563 |
-0.0271, -0.0084 |
0.0289, -0.0066 |
-0.0284, 0.0584 |