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WINDAS - Departamento de Ciências Atmosféricas
PRINCÍPIOS DE RADAR TÓPICOS AVANÇADOS CAPÍTULO 6 OSWALDO MASSAMBANI, Ph.D. Professor Titular Departamento de Ciências Atmosféricas Instituto de Astronomia, Astronomia Geofísica e Ciências Atmosféricas Universidade de São Paulo São Paulo – Brasil Tópicos avançados para a disciplina Meteorologia com Radar Departamento de Ciências Atmosféricas Instituto de Astronomia, Geofísica e Ciências Atmosféricas- IAG-USP Universidade de Sáo Paulo ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR Radares Perfiladores de Vento Radares Perfiladores de Vento Wind Profiler Radars ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Wind Profiler Radars Wind Profiler Radars PRINCÍPIOS DE RADAR C t t Contents Introduction User requirement Operational and frequency aspects Spectrum requirement Sharing aspects of wind profilers Japanese wind profiler network ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR INTRODUCTION • What is a Wind Profiler Radar? • Advantages of WPRs • RASS ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Wh i What is a wind profiler radar? i d fil d ? PRINCÍPIOS DE RADAR • Wind Profiler Radars (WPR ) (WPRs) are used to d obtain the vertical profiles of the wind over profiles of the wind over an unattended and sometimes remote area by detecting the tiny fraction of emitted power backscattered b k tt d from turbulence in the clear atmosphere clear atmosphere. Air flow Wind vector Reflected radio wave Reflected radio wave Emitted radio wave Principle of measuring wind by WPRs The frequency of reflected radio wave is changed Th f f fl d di i h d by Doppler effect. ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Example of wind profiler installation PRINCÍPIOS DE RADAR 449MHz WPR RASS This picture is from the Handbook(2008) ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil 6 Example of wind profiler installation Example of wind profiler installation PRINCÍPIOS DE RADAR Snow covered area type (f = 1357.5MHz) Generall structure G t t in i Japan J (f = 1357.5MHz) Redome: for antenna protection from snow ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Advantages of WPRs f PRINCÍPIOS DE RADAR • One One of the major advantages of wind profilers to other wind of the major advantages of wind profilers to other wind measurement systems is their ability to continuously monitor the wind field. • they can also be used to – – – – detect precipitation, measure major disturbances in the vertical velocity, measure the intensity turbulence, measure atmospheric stability. t h i t bilit ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Example of WPR’ss data Example of WPR data PRINCÍPIOS DE RADAR As an example mobile profiling system operating at 924 MHz produced the plot of wind velocity vs. altitude. The orientation of each flag represents wind direction as a function of altitude (vertical axis)and time (horizontal axis) while its colour represents function of altitude (vertical axis)and time (horizontal axis), while its colour represents wind speed. ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR Advantages of WPRs • WPRs can also provide detailed information on atmospheric virtual temperature through the addition of a Radio Acoustic virtual temperature through the addition of a Radio Acoustic Sounding System (RASS) ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil RASS PRINCÍPIOS DE RADAR Acoustic Wave • RASS utilizes an acoustic source that is matched in h i h di frequency so that the wavelength of the acoustic g wave is matched to half the wavelength of the radar transmitted electromagnetic transmitted electromagnetic wave. The speed of sound Electromagnetic Wave (The speed of light) RASS RASS WPR RASS RASS ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil RASS PRINCÍPIOS DE RADAR Acoustic Wave • RASS measures the speed of p the acoustic wave which is dependent upon temperature. • In this way RASS provides a t t f th remote measurement of the atmospheric virtual temperature. The speed of sound Electromagnetic Wave (The speed of light) RASS RASS WPR RASS RASS ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil User requirement PRINCÍPIOS DE RADAR A good way to examine the impact of user requirements upon wind profiler A good way to examine the impact of user requirements upon wind profiler operating parameters and design is to consider the following equation rewritten from [Gossard and Strauch, 1983]: ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil User requirement User requirement PRINCÍPIOS DE RADAR • • • • High temporal resolution High vertical resolution Obtaining wind data at high altitudes Reliable all‐weather operation ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil User requirement User requirement PRINCÍPIOS DE RADAR • High temporal resolution High temporal resolution 1. 2. 3. 4. Large aperture High peak power and high pulse repetition frequency (PRF) Long wave length Operation over a range of heights close to the radar • High PRF does not cause range ambiguity • Atmospheric backscattering are relatively large ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil User requirement User requirement PRINCÍPIOS DE RADAR • High vertical resolution – large aperture – high peak power, high PRF, and pulse compression to increase the average power – long wavelength – operation over a range of heights close to the radar where high PRF does not cause range ambiguity problems and where atmospheric backscattering and g g yp p g inverse‐height‐squared are relatively large ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil User requirement User requirement PRINCÍPIOS DE RADAR • Obtaining wind data at high altitudes – – – – large aperture; high peak power and pulse compression to increase the average power; long wavelength; long wavelength; large averaging times. ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil User requirement User requirement PRINCÍPIOS DE RADAR • Reliable all‐weather operation even if low‐scatter conditions – – – – frequency band; high average power and antenna aperture; higher receiver sensitivity; and low level of interference and system noise low level of interference and system noise. ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Monthly average of highest altitude for wind data PRINCÍPIOS DE RADAR highest altitu ude for wiind data [m] both Non‐Precipitation condition Precipitation condition Apr Winter in Japan low humidity Low Tropopause altitude Mar ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Operational and frequency aspects PRINCÍPIOS DE RADAR • Three types of WPRs Three types of WPRs • 50MHz band WPRs 50MH b d WPR – Middle and Upper atmosphere radar • 400MHz band WPRs • 1000MHz or more band WPRs – Boundary layer radar ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Comparison 50, 400, 1300MHz p , , PRINCÍPIOS DE RADAR 30km 15km Stratosphere 5km Troposphere ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR O Operational and frequency aspects ti l df t • MU radar( 50MHz band) is very large, powerful and short pulse – About 10 000m b 0 000 2, – 250kW or more peak, 12.5kW or more average – Pulse width: 1 microsecond Pulse width: 1 microsecond ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR Operational and frequency aspects Operational and frequency aspects • 400‐500MHz Wind profiler have been designed to : 400 500MH Wi d fil h b d i dt – Measure wind profiles from about 0.5 ‐ 16km – Vertical resolutions: • 250m( low altitude) • 1000m( high altitude) – Antenna gain is about 32dBi, Antenna gain is about 32dBi – Mean power of: • about 500W( low altitude) • About 2000W( high altitude) ( ) – Necessary bandwidth of less than 2MHz ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR Operational and frequency aspects f • 915MHz and 1270‐1375MHz Wind profiler have been designed to : boundary layer profiler, – – – – – Measure wind profiles up to about 5km Vertical resolutions are about 100m Antenna gain is below 30dBi Antenna gain is below 30dBi, Mean powers of about 50W Necessary bandwidths of 8MHz or more y ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR spectrum requirements t i t • Geographical separation and terrain shielding are effective protection against interference to and from other profilers. • Hence, an affordable network of wind profilers, say separated by at least 50 km over level terrain – less over more rugged or treed terrain could operate on the same frequency. treed terrain – could operate on the same frequency ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR spectrum requirements spectrum requirements • It It is generally agreed that 2 to 3 MHz of bandwidth are is generally agreed that 2 to 3 MHz of bandwidth are required near 400 MHz and 8 to 10 MHz near 1 000 MHz or 1 300 MHz ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR Sharing aspects of wind profilers • The bands for profiler use allocated by WRC‐97 were carefully selected to minimize the likelihood of interference to and l d i i i h lik lih d f i f d from other users of these bands. • • • • • • 46‐68 MHz in accordance with No. 5.162A 440‐450 440 450 MHz MHz 470‐494 MHz in accordance with No. 5.291A 904‐928 MHz in Region 2 only g y 1 270‐1 295 MHz 1 300‐1 375 MHz ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR An example of a WPR network l f k • The Japan Meteorological Agency (JMA) is operating a Wind profiler Network and Data Acquisition System (WINDAS) network. • Consist of thirty‐one 1.3GHz wind profiler ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR WINDAS • Purpose of WINDAS – Monitoring and Predicting the severe weather – Initial value of JMA Numerical Weather Prediction models – Combined with another data to comprehensive Upper‐air wind analysis ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR WINDAS Wind Profiler Network and Data Acquisition System ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil JMA Upper‐air Observation Network Observation Network PRINCÍPIOS DE RADAR 31 Wind Profilers Wind Profiler Control Center 16 Radiosonde stations Wakkanai Rumoi Sapporo Nemuro Muroran Obihiro Akita Miyako Sakata Takada Hamada FFukui k i Takamatu Yonago Tottori Wajima Oita Miham Izuhara a Fukuoka Hirado Kumamoto Ichiki Shiono‐ misaki Kagoshima Yakushima Kouchi hi Shimizu Nobeoka Kumagaya Tateno Mito Control Center (JMA Headquarters) (JMA Headquarters) Katuura Kawaguchiko Hachijojima Shizuoka N Nagoya Owase Naze Chichijima Minamidaitojima Ishigakijima Yonagunijima 1000km Minamitorishima JMA upper‐air observation network consisting of rawinsonde stations and wind profilers of WINDAS. ________________________________________________________________________________________________________ Upper‐wind observations are made at the interval of about 120km. Prof. Oswaldo Massambani –6.2 Wind Profiler Radars Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Data Flow in WINDAS WINDAS Profiler３ PRINCÍPIOS DE RADAR Profiler３０ Profiler２ 10 minute values of Doppler velocity and signal intensity l it d i l i t it being sent every 1 hour Profiler１ CONTROL CENTER（JMA Headquarters） Profiler３１ Data quality control and remote control of profilers being made Horizontal and vertical components of wind and signal intensity being sent with BUFR code every 1 hour C O S M E T S （JMA Central Computer） C O S M E T S （JMA Central Computer） N A P S Everｙ 6 hours Forecast made with Mesoscale Model ADESS Everｙ 1 hour Hourly analyzed y y atmospheric GPV 10 minute data being sent every 1 hour Wind profiler data ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Appearance pp PRINCÍPIOS DE RADAR General structure (Kagoshima: Department observed Ichiki) Snow‐covered area (Hokkaido: Department observed Obihiro) ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Major equipment and signal flow PRINCÍPIOS DE RADAR Module Unit Antenna System CONTROL CENTER Transmitter and Data Processer ________________________________________________________________________________________________________ Receiver System Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Block Diagram of the JMA Wind Profiler Network ( WINDAS) CONTROL CENTER CONTROL CENTER OBSERVATION SITE OBSERVATION SITE Type Ａ 中央監視局 観測局 PRINCÍPIOS DE RADAR Antenna System Transmitter and Transmitter and Receiver System Module Unit LAN Server 1 Server 2 L3SW L3SW HUB L2SW Operating Display Printer HUB Data Processer L2SW Leased line 国内基盤通信網 Type Ｂ Weather station Operating & Watching & Watching Quality Control Data Processer Outdoor L2SW L3SW Observation hut Observation hut Ｒｏｕ ｔｅｒ Ｒｏｕ ｔｅｒ HUB ISDN Operating Display Data Processer ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Characteristics of the JMA Wind Profiler Parameter PRINCÍPIOS DE RADAR Characteristics of WINDAS Antenna type Active phased array Antenna size 4mx4m Antenna gain 33 dBi Antenna beam width 4 degree (both elevation and azimuth direction) Antenna scan Vertical and four directions (elevation angle 75-80 degree) - These four directions make a right angle. Th b The beam di direction i changes h to another h every about b 0 0.4 4 seconds. d Frequency 1357.5 MHz power Peak p 1.8 kW Pulse width 0.67, 1.33, 2.00, 4.00 microseconds (selectable) Pulse repetition frequency (PRF) 5, 10, 15, 20 kHz (selectable) Pulse compression 8 bit Observation range 300m – about 5 km in height Observation interval 10 minutes (0.4 s x 5 beams x 28 times x 10 data of 1min) ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Data Quality Control Q y PRINCÍPIOS DE RADAR W P R R i Receiver W P R Si Signal Processor lP F F T / Wavelet White Noise Rejection Ground Clutter Rejection line Spectra Rejection Multi‐Peak Processing W P R D t P Data Processor Network C Center Receiving Power Check Horizontal Buddy Check Spectrum Width Check Surface Wind Check Velocity Unfolding Quadratic Surface Check Time‐Height Check Vertical Shear Check Spectrum Data 1 Min. Doppler Velocity pp y 10 Min. U VW U,V,W 10 Min. U,V,W Development of QC Algorithm JMA Central JMA Central Computer ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR Example of data Example of data ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Surface weather map PRINCÍPIOS DE RADAR Yakushima Typhoon was 980 hPa, moving to ENE 13kt near Yakushima WPR site. ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Satellite image PRINCÍPIOS DE RADAR ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil 台風１３号通過（屋久 島） Yakushima PRINCÍPIOS DE RADAR 2008/09/18 12：00－18： 00 Vertical velocity Vertical velocity 鉛直速度 Ｓ/Ｎ比 鉛直シアー 東西成分 南北成分 スペクトル幅 ペクト 幅 受信強度 ________________________________________________________________________________________________________ ヘリシティ Prof. Oswaldo Massambani –6.2 Wind Profiler Radars Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil 41 台風１３号通過（屋久 島） Yakushima PRINCÍPIOS DE RADAR 2008/09/18 12：00－18： 00 SNR 鉛直速度 Ｓ/Ｎ比 鉛直シアー 東西成分 南北成分 スペクトル幅 ペクト 幅 受信強度 ________________________________________________________________________________________________________ ヘリシティ Prof. Oswaldo Massambani –6.2 Wind Profiler Radars Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil 42 台風１３号通過（屋久 島） Yakushima PRINCÍPIOS DE RADAR 2008/09/18 00 12：00－18： Vertical Shear of horizontal wind speed Vertical Shear 鉛直速度 Ｓ/Ｎ比 鉛直シアー 東西成分 南北成分 スペクトル幅 受信強度 ________________________________________________________________________________________________________ ヘリシティ Prof. Oswaldo Massambani –6.2 Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Wind Profiler Radars 43 台風１３号通過（屋久 島） Yakushima PRINCÍPIOS DE RADAR 2008/09/18 00 12：00－18： East-West component East-west component 鉛直速度 Ｓ/Ｎ比 鉛直シアー 東西成分 南北成分 スペクトル幅 受信強度 ________________________________________________________________________________________________________ ヘリシティ Prof. Oswaldo Massambani –6.2 Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Wind Profiler Radars 44 台風１３号通過（屋久 島） Yakushima PRINCÍPIOS DE RADAR 2008/09/18 00 12：00－18： North-South component North-south component 鉛直速度 Ｓ/Ｎ比 鉛直シアー 東西成分 南北成分 スペクトル幅 受信強度 ________________________________________________________________________________________________________ ヘリシティ Prof. Oswaldo Massambani –6.2 Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Wind Profiler Radars 45 台風１３号通過（屋久 島） Yakushima PRINCÍPIOS DE RADAR 2008/09/18 00 12：00－18： Spectral width Spectral width 鉛直速度 Ｓ/Ｎ比 鉛直シアー 東西成分 南北成分 スペクトル幅 受信強度 ________________________________________________________________________________________________________ ヘリシティ Prof. Oswaldo Massambani –6.2 Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Wind Profiler Radars 46 台風１３号通過（屋久 島） Yakushima PRINCÍPIOS DE RADAR 2008/09/18 00 12：00－18： Received Intensity Received intensity 鉛直速度 Ｓ/Ｎ比 鉛直シアー 東西成分 南北成分 スペクトル幅 受信強度 ________________________________________________________________________________________________________ ヘリシティ Prof. Oswaldo Massambani –6.2 Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil Wind Profiler Radars 47 SUMMARY PRINCÍPIOS DE RADAR • WPRs are used to obtain the upper‐air wind and other useful data continuously. data continuously. • WPRs WPRs contains various type, and they use 50MHz band , 400 contains various type and they use 50MHz band 400‐ 500MHz band or 900‐1400MHz band. • In Japan, data of WPRs are used in various scenes, and very useful. ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil PRINCÍPIOS DE RADAR Sucesso para cada um de vocês ! Ob i d ! Obrigado ! _____________________ Prof. Oswaldo Massambani ________________________________________________________________________________________________________ Prof. Oswaldo Massambani – Departamento Ciências Atmosféricas ‐ Universidade de São Paulo – Brasil
