• Title/Summary/Keyword: Wind profiler

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Evaluation of Wind Speed Depending on Pulse Resolution of UHF Wind Profiler Radar (UHF 윈드프로파일러 레이더의 펄스 해상도에 따른 풍속의 정확성 평가)

  • Lee, Kyung-Hun;Kwon, Byung-Hyuk;Yoon, Hong-Joo
    • 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.

Rain Rate Estimation Process Using Doppler Spectrum of UHF Wind Profiler Radar

  • Kitichai Visessiri;Chaiwat Somboonlarp;Anuchit Waisontia;Lee, Nipha laruji;Narong Hemmakon
    • 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.

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Comparison of Data Measured by Doppler Instruments at 1,550 nm and 23.2 cm Wavelengths (1,550 nm와 23.2 cm 파장의 도플러 측기 관측자료 비교)

  • Geon-Myeong Lee;Byung-Hyuk Kwon;Kyung-Hun Lee;Zi-Woo Seo
    • 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.

Improvement in Wind Vector from UHF Wind Profiler Radar through Removing Ground Echo (지형에코 제거를 통한 UHF 윈드프로파일러의 바람벡터 개선)

  • Kim, Kwang-Ho;Kim, Park-Sa;Kim, Min-Seong;Kang, Dong-Hwan;Kwon, Byung Hyuk
    • Journal of Environmental Science International
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    • v.25 no.2
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    • pp.267-280
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    • 2016
  • Ground echo is radar return from stationary targets such as buildings and trees. Wind vectors from the wind profile radar in Gangneung are affected by ground echoes due to the complex mountainous terrain located to the west and the south. These ground echoes make a spurious peak close to the direct current (DC) line signal in Doppler spectra. Wind vectors polluted by ground clutters were determined from spectra of oblique beams. After eliminated the terrain echoes, the accuracy of wind vector compared with radiosonde was improved about 68.4% and its relative coefficient was increased from 0.58 to 0.97.

Retrieval of Radial Velocity and Moment Based on the Power Spectrum Density of Scattered 1290 MHz Signals with Altitude (1290 MHz 산란 신호의 고도별 파워 스펙트럼 밀도에 기반한 시선 속도와 모멘트 산출)

  • Jo, Won-Gi;Kwon, Byung-Hyuk;Yoon, Hong-Joo
    • 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.

An Analysis on Characteristics of Turbulence Energy Dissipation Rate from Comparison of Wind Profiler and Rawinsonde (연직바람관측장비와 레윈존데의 비교를 통한 난류 에너지 감소률의 특성 분석)

  • Kang, Woo Kyeong;Moon, Yun Seob;Jung, Ok Jin
    • Journal of the Korean earth science society
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    • v.37 no.7
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    • pp.448-464
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    • 2016
  • The purpose of this study is to optimize the parameters related to consensus coherency within the PCL 1300, the operating program of wind profiler, from a validation of wind data between rawinsonde and wind profiler at Chupungryeong ($36^{\circ}13^{\prime}$, $127^{\circ}59^{\prime}$) site in Korea. It is then to analyze the diurnal and seasonal characteristics of the turbulence energy dissipation rate (${\varepsilon}$) in clear and rainy days from March 2009 to February 2010. In comparison of the wind data between wind profiler and rawinsonde during April 22-23, 2010, it was shown in a big error more than $10ms^{-1}$ over the height of 3,000 meters in the zonal (u) and meridional (v) wind components. When removing more than $10ms^{-1}$ in each wind speed difference of u an v components between the two instruments, the correlation coefficients of these wind components were 0.92 and 0.88, respectively, and the root mean square errors were 3.07 and $1.06ms^{-1}$. Based on these results, when the data processing time and the minimum available data within the PCL 1300 program were adjusted as 30 minutes and 60%, respectively, the bias errors were small. In addition, as a result of an analysis of sensitivity to consensus coherency of u and v components within the PCL1300 program, u components were underestimated in radial coherency, instantaneous and winbarbs coherency, whereas v components were overestimated. Finally by optimizing parameters of the PCL1300 program, the diurnal and seasonal means of ${\varepsilon}$ at each height were higher in rainy days than those in clear days because of increasing in the vertical wind speed due to upward and downward motions. The mean ${\varepsilon}$ for clear and rainy days in winter was lower than those of other seasons, due to stronger horizontal wind speed in winter than those in other seasons. Consequently, when the turbulence energy dissipation rates in the vertical wind speed of more than ${\pm}10cm\;s^{-1}$ were excluded for clear and rainy days, the mean ${\varepsilon}$ in rainy days was 6-7 times higher than that in clear days, but when considering them, it was 4-5 times higher.

Study on TRX Channel Amplitude and Phase Calibration Method for a Radar Wind Profiler Based on 256 Active Phased Array (256 능동위상배열 기반 연직바람 관측장비의 송수신 채널 크기 및 위상 보정 방법 연구)

  • Jung, Woo-Jae;Lee, Jong-Chul
    • 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.

Improvement in the Simulation of Wind Fields Over the Complex Coastal Area, Korea (한반도 복잡 해안지역의 바람장 모의 개선)

  • Kim, Yoo-Keun;Bae, Joo-Hyun;Jeong, Ju-Hee;Kweon, Ji-Hye;Seo, Jang-Won;Kim, Yong-Sang
    • Journal of Environmental Science International
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    • v.15 no.5
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    • pp.417-430
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    • 2006
  • We focused on improvement in simulation of wind fields for the complex coastal area. Local Analysis and Prediction System(LAPS) was used as a data assimilation method to improve initial conditions. Case studies of different LAPS inputs were performed to compare improvement of wind fields. Five cases have been employed : I) non data assimilation, II) all available data, III) AWS, buoy, QuikSCAT, IV) AWS, buoy, wind profiler, V) AWS, buoy, AMEDAS. Data assimilation can supplement insufficiency of the mesoscale model which does not represent detailed terrain effect and small scale atmospheric flow fields. Result assimilated all available data showed a good agreement to the observations rather than other cases and estimated veil the local meteorological characteristics including sea breeze and up-slope winds. Result using wind profiler data was the next best thing. This implies that data assimilation with many high-resolution sounding data could contribute to the improvements of good initial condition in the complex coastal area. As a result, these indicated that effective data assimilation process and application of the selective LAPS inputs played an important role in simulating wind fields accurately in a complex area.

Field measurements of wind characteristics over hilly terrain within surface layer

  • He, Y.C.;Chan, P.W.;Li, Q.S.
    • Wind and Structures
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    • v.19 no.5
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    • pp.541-563
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    • 2014
  • This paper investigates the topographic effects on wind characteristics over hilly terrain, based on wind data recorded at a number of meteorological stations in or near complex terrain. The multiply data sources allow a more detailed investigation of the flow field than is normally possible. Vertical profiles of mean and turbulent wind components from a Sodar profiler were presented and then modeled as functions of height and wind speed. The correlations between longitudinal and vertical wind components were discussed. The phenomena of flow separation and generation of vortices were observed. The distance-dependence of the topographic effects on gust factors was revealed subsequently. Furthermore, the canyon effect was identified and discussed based on the observations of wind at a saddle point between two mountain peaks. This study aims to further understanding of the characteristics of surface wind over rugged terrain. The presented results are expected to be useful for structural design, prevention of pollutant dispersion, and validation of CFD (computational fluid dynamics) models or techniques over complex terrains.

Effect of Precipitation on Sea Surface Wind Scatterometry

  • Yang, Jilong;Zhang, Xuehu;Chen, Xiuwan;Esteban, Daniel;McLaughlin, David;Carswell, Jim;Chang, Paul;Black, Peter;Ke, Yinghai
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1359-1361
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    • 2003
  • A set of microwave remote sensing data collected with the newly developed UMass Imaging Wind and Rain Airborne Profiler (IWRAP) during the 2002 Atlantic Hurricane Season was analyzed to further our understanding of the effect of precipitation on scatterometer wind vector retrieval. Coincident surface wind speed and precipitation measurements were provided by the UMass Simultaneous Frequency Microwave Radiometer (SFMR). The differences between the wind estimations from IWRAP and SFMR under precipitation conditions of 0-100mm/hr and wind speed of 0-60m/s was calculated, from which the effect of precipitation on the wind vector retrieval using scatterometry is analyzed qualitatively.

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