Calibration Accuracy of the Dual-Polarization Receivers of the C-Band Swiss Weather Radar Network
Abstract
:1. Introduction
2. Description of Instruments, Acquired Data, and Retrieval Formula
3. Results
3.1. Weissfluhgipfel (WEI) Radar at an Altitude of 2850 m in Grisons (Next to Davos)
3.2. Monte Lema (Near Lugano) Radar at an Altitude of 1626 m
3.3. Albis (Near Zurich) Radar at an Altitude of 938 m
3.4. La Dole (Near Geneva) Radar at an Altitude of 1682 m
3.5. Pointe de la Plaine Morte (PPM) Radar at an Altitude of 2937 m in Valais (Next to Crans-Montana)
4. Discussion of the Results Including a Preliminary Attempt of Noise Subtraction
5. Summary, Conclusions, and Outlook
Acknowledgments
Author Contribution
Conflicts of Interest
References
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Weissfluhgipfel | Monte Lema | Albis | La Dole | P. de la Plaine Morte | |||||
---|---|---|---|---|---|---|---|---|---|
H | V | H | V | H | V | H | V | H | V |
2.5 dB | 2.7 dB | 2.6 dB | 2.15 dB | 2.25 dB | 2.4 dB | 2.7 dB | 2.8 dB | 2.25 dB | 2.55 dB |
44.8 dB | 45.0 dB | 45.0 dB | 45.0 dB | 45.2 dB | 45.0 dB | 45.0 dB | 45.1 dB | 44.6 dB | 44.7 dB |
Date | DRAO Reference | I5.5 Rx H | I5.5 Rx V | 10 log (H/V) | 10 log (H/DRAO) | 10 log (V/DRAO) |
---|---|---|---|---|---|---|
14 October 2015 | 21.40 ± 0.067 | 21.15 | 20.96 | 0.19 dB | −0.25 dB | −0.44 dB |
15 October 2015 | 21.51 ± 0.074 | 21.50 | 21.26 | 0.24 dB | −0.01 dB | −0.25 dB |
17 October 2015 | 21.71 ± 0.084 | 21.85 | 21.51 | 0.34 dB | +0.14 dB | −0.20 dB |
20 October 2015 | 21.92 ± 0.009 | 21.75 | 21.66 | 0.09 dB | −0.17 dB | −0.26 dB |
21 October 2015 | 21.95 ± 0.060 | 21.90 | 21.76 | 0.14 dB | −0.05 dB | −0.19 dB |
22 October 2015 | 21.90 ± 0.075 | 21.95 | 21.71 | 0.24 dB | +0.05 dB | −0.19 dB |
22 October 2015 | 21.90 ± 0.075 | 21.85 | 21.61 | 0.24 dB | −0.05 dB | −0.29 dB |
22 February 2016 | 21.30 ± 0.024 | 21.25 | 21.21 | 0.04 dB | −0.05 dB | −0.09 dB |
21 March 2016 | 21.16 ± 0.017 | 20.95 | 20.91 | 0.04 dB | −0.21 dB | −0.25 dB |
Average | 21.64 | 21.57 | 21.40 | +0.17 | −0.07 | −0.24 |
Standard dev. | ±0.30 | ±0.37 | ±0.32 | ±0.10 | ±0.13 | ±0.10 |
Date | DRAO Reference | I5.5 Rx H | I5.5 Rx V | 10 log (H/V) | 10 log (H/DRAO) | 10 log (V/DRAO) |
---|---|---|---|---|---|---|
2 November 2013 | 22.34 ± 0.079 | 22.32 | 22.17 | 0.15 dB | −0.02 dB | −0.17 dB |
29 April 2014 | 21.88 ± 0.037 | 21.52 | 21.37 | 0.15 dB | −0.36 dB | −0.51 dB |
7 August 2014 | 22.17 ± 0.039 | 21.97 | 21.87 | 0.10 dB | −0.20 dB | −0.30 dB |
28 January 2015 | 22.56 ± 0.039 | 22.32 | 22.37 | −0.05 dB | −0.24 dB | −0.19 dB |
7 April 2015 | 21.76 ± 0.125 | 21.67 | 21.57 | 0.10 dB | −0.09 dB | −0.19 dB |
21 March 2016 | 21.16 ± 0.017 | 20.98 | 20.90 | 0.08 dB | −0.18 dB | −0.26 dB |
Average | 21.98 | 21.80 | 21.71 | +0.09 | −0.18 | −0.27 |
Standard dev. | ±0.50 | ±0.52 | ±0.54 | ±0.07 | ±0.12 | ±0.13 |
Date | DRAO Reference | I5.5 Rx H | I5.5 Rx V | 10 log (H/V) | 10 log (H/DRAO) | 10 log (V/DRAO) |
---|---|---|---|---|---|---|
2 November 2013 | 22.34 ± 0.079 | 21.27 | 21.67 | −0.40 dB | −1.07 dB | −0.67 dB |
2 April 2014 | 22.51 ± 0.070 | 21.57 | 21.92 | −0.35 dB | −0.94 dB | −0.59 dB |
6 August 2014 | 22.19 ± 0.031 | 20.97 | 21.37 | −0.40 dB | −1.22 dB | −0.82 dB |
28 January 2015 | 22.56 ± 0.039 | 21.47 | 21.87 | −0.40 dB | −1.09 dB | −0.69 dB |
7 April 2015 | 21.76 ± 0.125 | 20.47 | 20.87 | −0.40 dB | −1.29 dB | −0.89 dB |
28 May 2015 | 21.28 ± 0.021 | 20.07 | 20.47 | −0.40 dB | −1.21 dB | −0.81 dB |
21 March 2016 | 21.16 ± 0.017 | 20.07 | 20.37 | −0.30 dB | −1.09 dB | −0.79 dB |
Average | 21.97 | 20.84 | 21.22 | −0.38 | −1.13 | −0.75 |
Standard dev. | ±0.58 | ±0.64 | ±0.65 | ±0.04 | ±0.12 | ±0.10 |
Date | DRAO Reference | I5.5 Rx H | I5.5 Rx V | 10 log (H/V) | 10 log (H/DRAO) | 10 log (V/DRAO) |
---|---|---|---|---|---|---|
28 January 2015 | 22.56 ± 0.039 | 22.24 | 22.04 | 0.20 dB | −0.32 dB | −0.52 dB |
7 April 2015 | 21.76 ± 0.125 | 21.59 | 21.54 | 0.05 dB | −0.17 dB | −0.22 dB |
Average | 22.10 | 21.91 | 21.79 | 0.13 | −0.19 | −0.31 |
Date | DRAO Reference | I5.5 Rx H | I5.5 Rx V | 10 log (H/V) | 10 log (H/DRAO) | 10 log (V/DRAO) |
---|---|---|---|---|---|---|
22 February 2016 | 21.30 ± 0.024 | 21.50 | 21.55 | −0.05 dB | +0.20 dB | +0.25 dB |
14 March 2016 | 21.27 ± 0.024 | 21.50 | 21.65 | −0.15 dB | +0.23 dB | +0.38 dB |
22 March 2016 | 21.14 ± 0.023 | 21.05 | 21.50 | −0.45 dB | −0.09 dB | +0.36 dB |
Average | 21.24 | 21.35 | 21.57 | −0.22 | +0.11 | +0.33 |
St. Deviation | ±0.09 | ±0.18 | ±0.07 | ±0.21 | ±0.18 | ±0.07 |
Average Error between Radar and DRAO Reference | Albis | Monte Lema | Weissfluhgipfel | |||
---|---|---|---|---|---|---|
H | V | H | V | H | V | |
SSun + Nunknown (as per Section 3) | −1.13 dB | −0.75 dB | −0.18 dB | −0.27 dB | −0.07 dB | −0.24 dB |
SSun + Nunknown − NEL40 | −1.62 dB | −1.25 dB | −0.67 dB | −0.76 dB | −0.58 dB | −0.77 dB |
Standard Deviation of the Error between Radar and DRAO Reference | Albis | Monte Lema | Weissfluhgipfel | |||
---|---|---|---|---|---|---|
H | V | H | V | H | V | |
SSun + Nunknown (as per Section 3) | 0.12 dB | 0.10 dB | 0.12 dB | 0.13 dB | 0.13 dB | 0.10 dB |
SSun + Nunknown − NEL40 | 0.16 dB | 0.17 dB | 0.15 dB | 0.18 dB | 0.16 dB | 0.12 dB |
% of Explained Variance between Radar and DRAO Reference | Albis | Monte Lema | Weissfluhgipfel | |||
---|---|---|---|---|---|---|
H | V | H | V | H | V | |
SSun + Nunknown | 97.3% | 98.6% | 94.8% | 94.8% | 90.6% | 91.4% |
SSun + Nunknown − NEL40 | 97.8% | 98.7% | 94.7% | 94.4% | 91.7% | 91.7% |
© 2016 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC-BY) license (http://creativecommons.org/licenses/by/4.0/).
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Gabella, M.; Boscacci, M.; Sartori, M.; Germann, U. Calibration Accuracy of the Dual-Polarization Receivers of the C-Band Swiss Weather Radar Network. Atmosphere 2016, 7, 76. https://doi.org/10.3390/atmos7060076
Gabella M, Boscacci M, Sartori M, Germann U. Calibration Accuracy of the Dual-Polarization Receivers of the C-Band Swiss Weather Radar Network. Atmosphere. 2016; 7(6):76. https://doi.org/10.3390/atmos7060076
Chicago/Turabian StyleGabella, Marco, Marco Boscacci, Maurizio Sartori, and Urs Germann. 2016. "Calibration Accuracy of the Dual-Polarization Receivers of the C-Band Swiss Weather Radar Network" Atmosphere 7, no. 6: 76. https://doi.org/10.3390/atmos7060076
APA StyleGabella, M., Boscacci, M., Sartori, M., & Germann, U. (2016). Calibration Accuracy of the Dual-Polarization Receivers of the C-Band Swiss Weather Radar Network. Atmosphere, 7(6), 76. https://doi.org/10.3390/atmos7060076