• Wind and Structures
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• v.17 no.4
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• pp.419-433
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• 2013

This paper investigates the vertical profiles of horizontal mean wind speed and direction based on the synchronized measurements from a Doppler radar profiler and an anemometer during 16 tropical cyclones at a coastal site in Hong Kong. The speed profiles with both open sea and hilly exposures were found to follow the log-law below a height of 500 m. Above this height, there was an additional wind speed shear in the profile for hilly upwind terrain. The fitting parameters with both the power-law and the log-law varied with wind strength. The direction profiles were also sensitive to local terrain setups and surrounding topographic features. For a uniform open sea terrain, wind direction veered logarithmically with height from the surface level up to the free atmospheric altitude of about 1200 m. The accumulated veering angle within the whole boundary layer was observed to be $30^{\circ}$. Mean wind direction under other terrain conditions also increased logarithmically with height above 500 m with a trend of rougher exposures corresponding to lager veering angles. A number of empirical parameters for engineering applications were presented, including the speed adjustment factors, power exponents of speed profiles, and veering angle, etc. The objective of this study aims to provide useful information on boundary layer wind characteristics for wind-resistant design of high-rise structures in coastal areas.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.2
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• pp.277-290
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• 2018

Wind data observed by wind profiler provide wind vectors with the altitudes using PCL1300, wind computation program. As a result of application with parameters set in program currently, it is difficult to compute wind vectors in the upper air over 3 km. This id because a very strict criterion for parameters removes large amounts of data. In this study, therefore, we improve the methods of application by resetting parameters to expand data collection area of wind vectors and reduce underestimation. Although the acquisition rate of the wind vector increased from 72.2% to 92.2%, the RMSE of the wind speed maintained 1.5 m/s - 3.1 m/s, which is less than 15% of the error rate at each altitude.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.6
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• pp.1191-1198
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• 2018

The wind profiler radar provides a standing profile of the wind vector and the atmospheric physical signal for the fixed point. Since the wind vector is calculated by the manufacturer's data processing program, the quality control of the date is limited. Therefore, understanding and exploiting the raw spectrum data need to improve the quality of the wind vector. The raw data of the wind vector is the power spectral density stored in binary form. In this study, an algorithm was completed to transform the raw data into the real spectral density, and the use of raw data was evaluated by retrieving zero-order and first-order moments of the spectral based on the spectrum quality control.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.5
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• pp.841-848
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• 2020

The 1.29 GHz wind profiler radar is a remote observation device that is useful not only for calculating wind vectors in clear air, but also for detecting rainfall. The Doppler spectrum symmetry test is essential in the horizontal wind treatment process. Since asymmetry may be detected in rainfall cases, it is necessary to reflect in the wind calculation algorithm that the sign of the radial velocity is the same according to the magnitude of the vertical velocity. In the summer of 2017 (June, July), a wind vector calculation algorithm by Bragg scattering and Rayleigh scattering was developed using Changwon wind profiler data, and verified by comparing it with radiosonde data at 6 hour intervals.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.3
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• pp.429-436
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• 2021

The wind profilers operated by the Korea Meteorological Administration observe in a low mode for intensive observation of the low levels and a high mode for intensive observation of the high levels. The LAP-3000 wind profiler installed in Bukgangneung and Changwon is characterized by the same sampling frequency of the low mode and the high mode, allowing to compare winds observed in both modes at the same altitude. As a result of analyzing the wind speed of the two points for one year in 2020, the correlation between the two modes was up to 0.2 lower than the correlation with radiosonde. The T-test for the wind speed of the two modes showed a particularly significant difference in October, where the temperature and specific humidity fluctuate frequently. The difference in the development of the atmospheric boundary layer affects the accuracy of the wind speed depending on the observation mode.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.5
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• pp.162-170
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• 2022

In this paper, the phased-array transceiver (TRX) channel amplitude and phase calibration method for a radar wind profiler (RWP) based on the 256 active phased array is discussed. Without the additional module, the TX and RX calibration paths were secured using couplers and switches in the TRX front ends and the TRX switching duplexers, and the amplitude and phase of the 256 TRX were calibrated using a gain and phase detector. The beam widths and side lobes of five beams (vertical, east, west, south, and north) of the calibrated 256 active phased array antenna were confirmed by a near-field which agreed well with the simulation results. The proposed calibration method can be easily applied to a system based on an active phased array operated in an outdoor environment.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1575-1577
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• 2002

In this research we propose a method far rain rate estimation by using Doppler spectrum's data of wind profiler. The Doppler spectrum is used to calculate the wind velocity and wind direction. But in this research uses the parameters from Doppler spectrum, it calculates the rain rate. The rain rate estimation in this method will be compared to the obtained rain rate from the surface rain gauge. Two equipments are installed in the same area. The correlation coefficient between rain rate measuring method is 0.65.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.6
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• pp.1041-1048
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• 2023

Wind LiDAR and Wind Profiler are devices that produce continuous vertical distribution of wind vector in high-resolution data, and their use has recently been increasing. Although the observation and data processing methods of the two devices are similar, differences in wind detection accuracy may occur depending on weather and operation settings. introduce the characteristics of the two instruments and wind calculation methods, and apply the latest instrument verification standards to evaluate their accuracy by comparing them with the wind observed with a radiosonde. Accordingly, a new direction for performance verification following the introduction of equipment and additional necessary complements are presented.

• Atmosphere
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• v.26 no.1
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• pp.47-58
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• 2016

On 10 July 2014, tornado outbreak occurred over Goyang province in Korea. This was the first supercell tornado ever reported or documented in Korea. The characteristics of the supercell tornado were investigated using an X-band polarimetric radar, surface meteorological observation, wind profiler, and operational numerical weather prediction (Regional Data Assimilation and Prediction System, RDAPS). The supercell tornado developed along a preexisting dryline that was contributed to surface wind shear. The radar analyses examined here show that the supercell tornado indicated a hook echo with mesocyclone. The decending reflectivity core as well was detected before tornadogenesis and prior to intensification of supercell. The supercell tornado exhibited characteristics similar to typical supercell tornado over the Great Plains of the United States, such as hook echo, bounded weak echo region, and slower movement speed relative to the mean wind. Compared to the typical supercell tornado over U.S., this tornado showed horizontal scale of the mesocyclone was relatively smaller and left-mover.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.3
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• pp.423-428
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• 2021

The performance of wind profilers were evaluated in Bukgangneung and Changwon, where both wind profilers and radiosonde are being operated. From December 2019 to November 2020, the acquisition rate of wind speed data by altitude and month was investigated and compared with the wind speed of radiosonde. The acquisition rate of normal data increased at the minimal observable altitude, and then decreased again from 2 km or more at the two observation sites. The acquisition rate was high in summer (June, July, August), and low in winter (December, January, February). The results compared with radiosonde showed high correlation of 0.9 in the high mode and 0.8 in the low mode.