Availability of three-dimensionally contiguous volume-

1. ～2m ～2m 上空3000mの雨雲から、地上に雨粒が到達する時間は10分程度 １５：００ １５：１０ １５：２０ ＜Basic concept＞ High cost performance ・General (2-dim) phased array radar is high-priced. ・Combination of 1-dim array and DBF(Digital Beam Forming)to realize 3-dim obs. in 10 sec. ・Target price is in the same range of the parabolic antenna radar system. • ＜Antenna scan＞ • 3-dim volume scan in a rotation • Horizontal beam (～1°) made by a slot-array antenna • 1-dim active phased array in vertical direction- Fan beam ( >3°) Tx in vertical- Simultaneous pencil beams Rx (～1°) made by DBF • (to increase the num of samples) 雨粒が大きく成長し、 降下を始める。 上空で雨粒が急速に 成長を開始 雨雲の移動 降　雨 上昇気流 上昇気流 上昇気流 大きな雨粒が、 地上に到達。 積乱雲が発生 観測データ industry-academia-government project NICT-commissioned research project Toshiba & Osaka Univ. ○○県△△市竜巻注意情報 平成××年4月20日10時29分 △△地方気象台発表 ○○県△△市では竜巻発生のおそれがあります。 発生予測時刻と場所は以下の地図のとおりです。 頑丈な建物内に移動するなど、安全確保に努めてください。 Water discharged by dams Flood forecast, Landslide prediction Data assimilation, Tornado warnings [JMA] Air traffic control Analysis of the mechanism research, [Institute, University] Evacuation call [municipality] Next-generation Doppler radar Train operating Sewerage pump [municipality] Information service [Weather company] Availability of three-dimensionally contiguous volume- scan data measured by phased array weather radar 1 NICT, Japan (satoh@nict.go.jp) 2 Osaka University, Japan 3 Toshiba Corporation, Japan Shinsuke Satoh 1 , Tomoo Ushio 2, Eiichi Yoshikawa 2, Zen Kawasaki 2, Fumihiko Mizutani 3, Masakazu Wada 3, and Toshio Iguchi 1 　　15時20分頃、A地区で非常に 　　強い雨が突然降り出す 　　 15～16時頃まで、A地区では 　　夕立が発生しやすい状態 　　現在、A地区で非常に強い雨を 降らせている雨雲は、15時40分 頃にB地区に移動する 通信事業者 データセンター 1-1. Social Background in Japan 2-1. Research and Development of a Phased-array Radar System 3-1. 3D Contiguous Volume Data ・ In Japan, severe weather disasters caused by localized heavy rainfalls or tornadoes have occurred frequently in the last several years. ・ The River Bureau of MLIT has installed multiple X-band MP-radar within the area of C-band radar observation network. To measure and predict sudden and localized meteorological disasters, we should research and develop a next-generation Doppler radar which measures 3-dimentional structure of heavy rainfalls, tornadoes at a resolution of 100 m within 10 sec. Flash flood in the Toga river, Kobe （28 July 2008） RHI The observation area of MLIT C-band radar and X-band MP radar (small blue circles). Fatal accident in the sewerage at Zoshigaya, Tokyo （5 Aug 2008） Subject A: Dev. of phased array radar system ・ measure 30 x 30 x 14 km in less than 10 sec ・ grid size less than 100 m (after coordinate conversion) ・ reduction of interference tech for the network obs. ・ remote operation, real-time data proc. & delivery・ low-cost system, reduction of maintenance cost. CAPPIs Num of occurrences of heavy rainfalls (> 50 mm/h) Phased-array radar will provides 3-dim. filled data every 10 seconds. We should consider useful display method for practical users. One of ideas is time-series of vertical slices instead of commonly used CAAPIs. Vertical slice with 3D surface 3D display: Fujiyoshi, et al. 1991, J. Atmos. Ocean. Tech., 869-872. CAPPI & RHI: Yoshikawa, et al. 2010, IEEE Trans. Geo. Rem. Sens., 3225-3235. F3 tornado in Saroma, Hokkaido （7 Nov 2006） Railcars overturned by tornado in Nobeoka, Miyazaki (17 Sept 2006) Subject B: Performance assessment & field experiment ・ Dev. of ground clutter reduction technique ・ Simulation for over-sampling, beam sharpening, etc.・ Radar operation technique to satisfy the user needs ・ Validation in field experiments for practical use 3-2. Application Field 2008 1998 1978 1988 R&D Schedule 1-2. Problems of Commonly Used Weather Radar Beam width 2-2. Conceptual Design Observation Gap - Observation gap by the earth curvature - Radar beam spread are appeared at a long range A 3-dim volume scan by a parabolic antenna requires time of 5 –10 min Short-range radar network( high spatial resolution ) Electrical scan radar( high temporal resolution ) A low-cost phased array radar The solution is … 4. Summary 1-3. Possible Widespread Utilization • We are developing an X-band one-dimensional phased-array radar with a combination of fan-beam Tx and DBF Rx. • The radar system will be manufactured in 2011, and will be validated in field experiments in 2012 in Osaka, Japan. • We are promoting this project for not only research use but also practical use at the earliest possible time. For the practical users, we should consider the effective utilization method and the useful products of the three-dimensional high-resolution data. Short-time forecast of rainfalls Short-time forecast of tornadoes • As a low-cost rapid-scan radar system, we have adopted a one-dimensional active phased-array in the elevation direction and a mechanical rotation in the azimuth direction. • To increase the number of samples in a limited time, we use a combination of fan-beam transmitting and DBF (Digital Beam Forming) receiving. １３：５１：１０、35.6789N, 140.1234E メソサイクロン（竜巻の親雲）から 漏斗雲（竜巻）が発生 72 km/h １３：５１：２０、35.6801N, 140.1251E 竜巻がタッチダウン １３：５１：３５ あなたのいる場所は、数分以内に竜巻が接近します。直ちに安全な建物（トイレなど）に避難して下さい。 １３：５１：２５あなたの直ぐ近くで竜巻が発生。１０秒以内に身近なものに隠れて下さい。 フェーズドアレイレーダー 周囲１km以内の人の携帯に緊急連絡 竜巻の進行方向10km以内の人の携帯に緊急連絡