Spectral parameters estimation in precipitation for 50 MHz band atmospheric radars
Tong Gan, Masayuki K. Yamamoto, Hiroyuki Hashiguchi, Hajime Okamoto, Mamoru Yamamoto
Fifty megahertz band atmospheric radars (ARs) can detect clear air echoes and hydrometeor echoes simultaneously. However, in order to calculate spectral parameters (i.e., echo power, Doppler velocity, and spectrum width) of the clear air echo accurately, the clear air echo must be separated from the hydrometeor echo well. In this study, we propose methods (top method and two-echo method) for calculating the spectral parameters in precipitation region. The top method is used when raindrops or solid hydrometeors with small echo intensities exist. The top method sets an echo cut level by using the peak intensity of the clear air echo. The echo cut level is used for separating clear air echoes from hydrometeor echoes. The two-echo method is used when solid hydrometeors with large echo intensities exist. The two-echo method sets the echo cut level by using the local minimum of echo intensity between the clear air echo and the hydrometeor echo. Measurement results obtained by the vertical beam of the middle and upper atmosphere radar during a precipitation event on 26 October 2009 were used for evaluating the performance of the top and two-echo methods. The echo cut levels of the top and two-echo methods were determined from numerical simulation. The measurement results demonstrate that the top and two-echo methods are useful for reducing errors of spectral parameters.
Radio Science
https://doi.org/10.1002/2014RS005643
hydrometeors
Upper atmosphere
Precipitation (meteorology)
middle atmosphere
Gan, T., Yamamoto, M. K., Hashiguchi, H., Okamoto, H., & Yamamoto, M. (2015). Spectral parameters estimation in precipitation for 50 MHz band atmospheric radars. Radio Science, 50(8), 789-803. https://doi.org/10.1002/2014RS005643
Spectral parameters estimation in precipitation for 50 MHz band atmospheric radars. / Gan, Tong; Yamamoto, Masayuki K.; Hashiguchi, Hiroyuki; Okamoto, Hajime; Yamamoto, Mamoru.
In: Radio Science, Vol. 50, No. 8, 01.08.2015, p. 789-803.
Gan, T, Yamamoto, MK, Hashiguchi, H, Okamoto, H & Yamamoto, M 2015, 'Spectral parameters estimation in precipitation for 50 MHz band atmospheric radars', Radio Science, vol. 50, no. 8, pp. 789-803. https://doi.org/10.1002/2014RS005643
Gan T, Yamamoto MK, Hashiguchi H, Okamoto H, Yamamoto M. Spectral parameters estimation in precipitation for 50 MHz band atmospheric radars. Radio Science. 2015 Aug 1;50(8):789-803. https://doi.org/10.1002/2014RS005643
Gan, Tong ; Yamamoto, Masayuki K. ; Hashiguchi, Hiroyuki ; Okamoto, Hajime ; Yamamoto, Mamoru. / Spectral parameters estimation in precipitation for 50 MHz band atmospheric radars. In: Radio Science. 2015 ; Vol. 50, No. 8. pp. 789-803.
@article{f4c18666a89a46e794ea45a430460921,
title = "Spectral parameters estimation in precipitation for 50 MHz band atmospheric radars",
abstract = "Fifty megahertz band atmospheric radars (ARs) can detect clear air echoes and hydrometeor echoes simultaneously. However, in order to calculate spectral parameters (i.e., echo power, Doppler velocity, and spectrum width) of the clear air echo accurately, the clear air echo must be separated from the hydrometeor echo well. In this study, we propose methods (top method and two-echo method) for calculating the spectral parameters in precipitation region. The top method is used when raindrops or solid hydrometeors with small echo intensities exist. The top method sets an echo cut level by using the peak intensity of the clear air echo. The echo cut level is used for separating clear air echoes from hydrometeor echoes. The two-echo method is used when solid hydrometeors with large echo intensities exist. The two-echo method sets the echo cut level by using the local minimum of echo intensity between the clear air echo and the hydrometeor echo. Measurement results obtained by the vertical beam of the middle and upper atmosphere radar during a precipitation event on 26 October 2009 were used for evaluating the performance of the top and two-echo methods. The echo cut levels of the top and two-echo methods were determined from numerical simulation. The measurement results demonstrate that the top and two-echo methods are useful for reducing errors of spectral parameters.",
author = "Tong Gan and Yamamoto, {Masayuki K.} and Hiroyuki Hashiguchi and Hajime Okamoto and Mamoru Yamamoto",
doi = "10.1002/2014RS005643",
journal = "Radio Science",
publisher = "American Geophysical Union",
T1 - Spectral parameters estimation in precipitation for 50 MHz band atmospheric radars
AU - Gan, Tong
AU - Yamamoto, Masayuki K.
AU - Hashiguchi, Hiroyuki
AU - Okamoto, Hajime
AU - Yamamoto, Mamoru
N2 - Fifty megahertz band atmospheric radars (ARs) can detect clear air echoes and hydrometeor echoes simultaneously. However, in order to calculate spectral parameters (i.e., echo power, Doppler velocity, and spectrum width) of the clear air echo accurately, the clear air echo must be separated from the hydrometeor echo well. In this study, we propose methods (top method and two-echo method) for calculating the spectral parameters in precipitation region. The top method is used when raindrops or solid hydrometeors with small echo intensities exist. The top method sets an echo cut level by using the peak intensity of the clear air echo. The echo cut level is used for separating clear air echoes from hydrometeor echoes. The two-echo method is used when solid hydrometeors with large echo intensities exist. The two-echo method sets the echo cut level by using the local minimum of echo intensity between the clear air echo and the hydrometeor echo. Measurement results obtained by the vertical beam of the middle and upper atmosphere radar during a precipitation event on 26 October 2009 were used for evaluating the performance of the top and two-echo methods. The echo cut levels of the top and two-echo methods were determined from numerical simulation. The measurement results demonstrate that the top and two-echo methods are useful for reducing errors of spectral parameters.
AB - Fifty megahertz band atmospheric radars (ARs) can detect clear air echoes and hydrometeor echoes simultaneously. However, in order to calculate spectral parameters (i.e., echo power, Doppler velocity, and spectrum width) of the clear air echo accurately, the clear air echo must be separated from the hydrometeor echo well. In this study, we propose methods (top method and two-echo method) for calculating the spectral parameters in precipitation region. The top method is used when raindrops or solid hydrometeors with small echo intensities exist. The top method sets an echo cut level by using the peak intensity of the clear air echo. The echo cut level is used for separating clear air echoes from hydrometeor echoes. The two-echo method is used when solid hydrometeors with large echo intensities exist. The two-echo method sets the echo cut level by using the local minimum of echo intensity between the clear air echo and the hydrometeor echo. Measurement results obtained by the vertical beam of the middle and upper atmosphere radar during a precipitation event on 26 October 2009 were used for evaluating the performance of the top and two-echo methods. The echo cut levels of the top and two-echo methods were determined from numerical simulation. The measurement results demonstrate that the top and two-echo methods are useful for reducing errors of spectral parameters.
U2 - 10.1002/2014RS005643
DO - 10.1002/2014RS005643
JO - Radio Science
JF - Radio Science
10.1002/2014RS005643