Dr. Toshio Iguchi Profile

Dr. Toshio Iguchi

at National Inst of Information and Communications Techn

SPIE Involvement:

Conference Program Committee | Symposium Chair | Symposium Committee | Author

Publications (25)

Proceedings Article | 30 October 2018

Current status of the Dual-frequency precipitation Radar on the Global Precipitation Measurement core spacecraft and scan pattern change test operations results

Kinji Furukawa, Kosuke Yamamoto, Takuji Kubota, Riko Oki, Toshio Iguchi

Proc. SPIE. 10776, Remote Sensing of the Atmosphere, Clouds, and Precipitation VII

KEYWORDS: Radar, Observatories, Aerospace engineering, Calibration, Satellites, Radiometry, Space operations, Microwave radiation, Ku band, Communication and information technologies

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Proceedings Article | 22 October 2018

Possible improvement of the GPM's Dual-frequency Precipitation Radar (DPR) algorithm

Toshio Iguchi, Kaya Kanemaru, Atsushi Hamada

Proc. SPIE. 10776, Remote Sensing of the Atmosphere, Clouds, and Precipitation VII

KEYWORDS: Radar, Detection and tracking algorithms, Signal attenuation, Satellites, Reflectivity, Image classification, Algorithm development, Ka band, Ku band

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Proceedings Article | 29 September 2017

Prime mission results of the dual-frequency precipitation radar on the global precipitation measurement core spacecraft and the version 5 GPM standard products

K. Furukawa, T. Nio, R. Oki, T. Kubota, T. Iguchi

Proc. SPIE. 10423, Sensors, Systems, and Next-Generation Satellites XXI

KEYWORDS: Radar, Aerospace engineering, Calibration, Satellites, Satellite communications, Radiometry, Space operations, Microwave radiation, Communication and information technologies, Standards development

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Proceedings Article | 19 October 2016

Current status of the dual-frequency precipitation radar on the global precipitation measurement core spacecraft and the new version of GPM standard products

K. Furukawa, T. Nio, T. Konishi, T. Masaki, T. Kubota, R. Oki, T. Iguchi

Proc. SPIE. 10000, Sensors, Systems, and Next-Generation Satellites XX

KEYWORDS: Radar, Aerospace engineering, Calibration, Satellites, Satellite imaging, Space operations, Microwave radiation, Ka band, Ku band, Communication and information technologies

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Proceedings Article | 12 October 2015

Current status of the dual-frequency precipitation radar on the global precipitation measurement core spacecraft

K. Furukawa, T. Nio, T. Konishi, R. Oki, T. Masaki, T. Kubota, T. Iguchi, H. Hanado

Proc. SPIE. 9639, Sensors, Systems, and Next-Generation Satellites XIX

KEYWORDS: Radar, Observatories, Aerospace engineering, Calibration, Satellites, Antennas, Radiometry, Space operations, Microwave radiation, Communication and information technologies

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The Dual-frequency Precipitation Radar (DPR) on the Global Precipitation Measurement (GPM) core satellite was developed by Japan Aerospace Exploration Agency (JAXA) and National Institute of Information and Communications Technology (NICT). The GPM is a follow-on mission of the Tropical Rainfall Measuring Mission (TRMM). The objectives of the GPM mission are to observe global precipitation more frequently and accurately than TRMM. The frequent precipitation measurement about every three hours will be achieved by some constellation satellites with microwave radiometers (MWRs) or microwave sounders (MWSs), which will be developed by various countries. The accurate measurement of precipitation in mid-high latitudes will be achieved by the DPR. The GPM core satellite is a joint product of National Aeronautics and Space Administration (NASA), JAXA and NICT. NASA developed the satellite bus and the GPM Microwave Imager (GMI), and JAXA and NICT developed the DPR. JAXA and NICT developed the DPR through procurement. The configuration of precipitation measurement using active radar and a passive radiometer is similar to TRMM. The major difference is that DPR is used in GPM instead of the precipitation radar (PR) in TRMM. The inclination of the core satellite is 65 degrees, and the nominal flight altitude is 407 km. The non-sun-synchronous circular orbit is necessary for measuring the diurnal change of rainfall similarly to TRMM. The DPR consists of two radars, which are Ku-band (13.6 GHz) precipitation radar (KuPR) and Ka-band (35.5 GHz) precipitation radar (KaPR). Both KuPR and KaPR have almost the same design as TRMM PR. The DPR system design and performance were verified through the ground test. GPM core observatory was launched at 18:37:00 (UT) on February 27, 2014 successfully. DPR orbital check out was completed in May 2014. The results of orbital checkout show that DPR meets its specification on orbit. After completion of initial checkout, DPR started Normal Operations and Initial Calibration and Validation period was started. JAXA conducted internal calibrations, external calibrations and phase code changes to mitigate KuPR sidelobe clutter effect. JAXA evaluated these operations results and concluded that DPR data could go public. DPR products were released to the public on Sep. 2, 2014 and Normal Observation Operation period was started. JAXA is continuing DPR trend monitoring, calibration operations to confirm that DPR keeps its function and performance on orbit.

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Proceedings Article | 7 October 2014

Orbital checkout result of the dual-frequency precipitation radar on the global precipitation measurement core spacecraft

K. Furukawa, M. Kojima, T. Miura, Y. Hyakusoku, H. Kai, T. Ishikiri, T. Iguchi, H. Hanado, K. Nakagawa, M. Okumura

Proc. SPIE. 9241, Sensors, Systems, and Next-Generation Satellites XVIII

KEYWORDS: Radar, Observatories, Aerospace engineering, Calibration, Satellites, Antennas, Radiometry, Space operations, Microwave radiation, Communication and information technologies

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The Dual-frequency Precipitation Radar (DPR) on the Global Precipitation Measurement (GPM) core satellite was developed by Japan Aerospace Exploration Agency (JAXA) and National Institute of Information and Communications Technology (NICT). The GPM is a follow-on mission of the Tropical Rainfall Measuring Mission (TRMM). The objectives of the GPM mission are to observe global precipitation more frequently and accurately than TRMM. The frequent precipitation measurement about every three hours will be achieved by some constellation satellites with microwave radiometers (MWRs) or microwave sounders (MWSs), which will be developed by various countries. The accurate measurement of precipitation in mid-high latitudes will be achieved by the DPR. The GPM core satellite is a joint product of National Aeronautics and Space Administration (NASA), JAXA and NICT. NASA developed the satellite bus and the GPM Microwave Imager (GMI), and JAXA and NICT developed the DPR. JAXA and NICT developed the DPR through procurement. The contract for DPR was awarded to NEC TOSHIBA Space Systems, Ltd. The configuration of precipitation measurement using active radar and a passive radiometer is similar to TRMM. The major difference is that DPR is used in GPM instead of the precipitation radar (PR) in TRMM. The inclination of the core satellite is 65 degrees, and the flight altitude is about 407 km. The non-sun-synchronous circular orbit is necessary for measuring the diurnal change of rainfall similarly to TRMM. The DPR consists of two radars, which are Ku-band (13.6 GHz) precipitation radar (KuPR) and Ka-band (35.5 GHz) precipitation radar (KaPR). Both KuPR and KaPR have almost the same design as TRMM PR. The DPR system design and performance were verified through the development test and the proto flight test. DPR had handed over to NASA and integration of the DPR to the GPM core spacecraft had completed in May 2012. GPM core spacecraft satellite system test had completed in November 2013. The result of the satellite system test concerning to the DPR satisfied system requirements. GPM core observatory was shipped to Tanegashima Space Center, JAPAN and Launch Site Operations had started on November 2013 and GPM core observatory was launched at 18:37:00 (UT) on February 27, 2014 successfully. DPR orbital check out was completed in May 2014. The orbital check out and the initial calibration and validation operation result of DPR is reported.

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Proceedings Article | 9 November 2012

Dual-frequency precipitation radar (DPR) development on the global precipitation measurement (GPM) core observatory

M. Kojima, T. Miura, K. Furukawa, Y. Hyakusoku, T. Ishikiri, H. Kai, T. Iguchi, H. Hanado, K. Nakagawa

Proc. SPIE. 8528, Earth Observing Missions and Sensors: Development, Implementation, and Characterization II

KEYWORDS: Radar, Observatories, Aerospace engineering, Calibration, Satellites, Antennas, Radiometry, Space operations, Microwave radiation, Pulmonary function tests

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Proceedings Article | 9 November 2012

An overview of the precipitation retrieval algorithm for the dual-frequency precipitation radar (DPR) on the global precipitation measurement (GPM) mission's core satellite

Toshio Iguchi, Shinta Seto, Robert Meneghini, Naofumi Yoshida, Jun Awaka, Takuji Kubota, Toshiaki Kozu, V. Chandra, Minda Le, Liang Liao, Simone Tanelli, Steve Durden

Proc. SPIE. 8528, Earth Observing Missions and Sensors: Development, Implementation, and Characterization II

KEYWORDS: Radar, Scattering, Signal attenuation, Satellites, Particles, Meteorology, Algorithm development, Ka band, Ku band, Liquids

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Proceedings Article | 9 November 2012

GPM science status in Japan

Kenji Nakamura, Riko Oki, Toshio Iguchi

Proc. SPIE. 8528, Earth Observing Missions and Sensors: Development, Implementation, and Characterization II

KEYWORDS: Radar, Signal attenuation, Satellites, Particles, Reflectivity, Meteorology, Radiometry, Algorithm development, Microwave radiation, Ka band

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Proceedings Article | 8 November 2012

Use of ASTER GDEM for separating rain echo and surface clutter in the radar observation of rain from space

Jun Awaka, Toshio Iguchi

Proc. SPIE. 8523, Remote Sensing of the Atmosphere, Clouds, and Precipitation IV

KEYWORDS: Radar, Satellites, Remote sensing, Estimation theory, Computer simulations, Clouds, Antennas, Meteorology, Atmospheric sensing, Current controlled current source

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Proceedings Article | 25 October 2012

Status of proto-flight model of the dual-frequency precipitation radar for the global precipitation measurement

T. Miura, M. Kojima, K. Furukawa, Y. Hyakusoku, T. Ishikiri, H. Kai, T. Iguchi, H. Hanado, K. Nakagawa

Proc. SPIE. 8533, Sensors, Systems, and Next-Generation Satellites XVI

KEYWORDS: Radar, Aerospace engineering, Satellites, Meteorology, Radiometry, Space operations, Microwave radiation, Ka band, Ku band, Communication and information technologies

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The Dual-frequency Precipitation Radar (DPR) on the Global Precipitation Measurement (GPM) core spacecraft is being developed by Japan Aerospace Exploration Agency (JAXA) and National Institute of Information and Communications Technology (NICT). The GPM is a follow-on mission of the Tropical Rainfall Measuring Mission (TRMM). The objectives of the GPM mission are to observe global precipitation more frequently and accurately than TRMM. The frequent precipitation measurement about every three hours will be achieved by some constellation satellites with microwave radiometers (MWRs) or microwave sounders (MWSs), which will be developed by various countries. The accurate measurement of precipitation in mid-high latitudes will be achieved by the DPR. The GPM core satellite is a joint product of National Aeronautics and Space Administration (NASA), JAXA and NICT. NASA is developing the satellite bus and the GPM microwave radiometer (GMI), and JAXA and NICT are developing the DPR. JAXA and NICT are developing the DPR through procurement. The contractor for DPR is NEC TOSHIBA Space Systems, Ltd. The configuration of precipitation measurement using an active radar and a passive radiometer is similar to TRMM. The major difference is that DPR is used in GPM instead of the precipitation radar (PR) in TRMM. The inclination of the core spacecraft is 65 degrees, and the flight altitude is about 407 km. The non-sun-synchronous circular orbit is necessary for measuring the diurnal change of rainfall similarly to TRMM. The DPR consists of two radars, which are Ku-band (13.6 GHz) precipitation radar (KuPR) and Ka-band (35.55 GHz) precipitation radar (KaPR). According to the different detectable dynamic ranges, The KaPR will detect snow and light rain, and the KuPR will detect heavy rain. In an effective dynamic range in both KuPR and KaPR, drop size distribution information and more accurate rainfall estimates will be provided by a dual-frequency algorithm. The proto-flight test for DPR have finished in February 2012 and DPR integration on GPM core spacecraft was successfully completed in May 2012. The status of proto-flight model of DPR will be presented.

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Proceedings Article | 3 October 2011

Status of proto-flight test of the dual-frequency precipitation radar for the global precipitation measurement

T. Miura, M. Kojima, K. Furukawa, Y. Hyakusoku, T. Iguchi, H. Hanado, K. Nakagawa, M. Okumura

Proc. SPIE. 8176, Sensors, Systems, and Next-Generation Satellites XV

KEYWORDS: Radar, Aerospace engineering, Satellites, Inspection, Meteorology, Radiometry, Neodymium, Microwave radiation, Electromagnetism, Communication and information technologies

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Proceedings Article | 16 November 2010

Dual-frequency radar (DPR) and the global precipitation measurement (GPM) in Japan

Kenji Nakamura, Riko Oki, Toshio Iguchi

Proc. SPIE. 7856, Remote Sensing and Modeling of the Atmosphere, Oceans, and Interactions III

KEYWORDS: Radar, Signal attenuation, Satellites, Reflectivity, Antennas, Meteorology, Radiometry, Algorithm development, Microwave radiation, Ka band

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Proceedings Article | 13 October 2010

Status of development of the GPM Dual-frequency Precipitation Radar (DPR), algorithm development, and ground validation activities

Misako Kachi, Takeshi Miura, Riko Oki, Shuji Shimizu, Takuji Kubota, Naofumi Yoshida, Yasutoshi Hyakusoku, Kinji Furukawa, Masahiro Kojima, Toshio Iguchi, Kenji Nakamura

Proc. SPIE. 7826, Sensors, Systems, and Next-Generation Satellites XIV

KEYWORDS: Radar, Detection and tracking algorithms, Signal attenuation, Calibration, Satellites, Meteorology, Algorithm development, Microwave radiation, Ka band, Standards development

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Proceedings Article | 23 September 2009

Status of algorithm development and CAL/VAL plans in the JAXA GPM project

Misako Kachi, Riko Oki, Shuji Shimizu, Takuji Kubota, Naofumi Yoshida, Toshio Iguchi, Kenji Nakamura

Proc. SPIE. 7474, Sensors, Systems, and Next-Generation Satellites XIII

KEYWORDS: Radar, Imaging systems, Signal attenuation, Calibration, Satellites, Satellite imaging, Meteorology, Radiometry, Algorithm development, Microwave radiation

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Proceedings Article | 8 December 2008

TRMM PR algorithms version 6 status and plans for version 7

Ken'ichi Okamoto, Robert Meneghini, Toshio Iguchi, Jun Awaka, Shuji Shimizu

Proc. SPIE. 7152, Remote Sensing of the Atmosphere and Clouds II

KEYWORDS: Radar, Statistical analysis, Signal attenuation, Calibration, Error analysis, Reliability, Reflectivity, Receivers, Clouds, Meteorology

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Proceedings Article | 2 December 2008

Evaluation of the estimation method for nonuniformity of rainfall within a footprint of TRMM/PR using the data during 180-degree yaw maneuver

Nobuhiro Takahashi, Toshio Iguchi

Proc. SPIE. 7154, Microwave Remote Sensing of the Atmosphere and Environment VI

KEYWORDS: Radar, Solar energy, Sun, Detection and tracking algorithms, Signal attenuation, Satellites, Clouds, Data processing, Meteorology, Data centers

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The Tropical Rainfall Measuring Mission (TRMM) satellite performs 180-degree yaw maneuver (yaw-around) when the solar beta angle which is the angle between the satellite orbit plane and the direction to the sun crosses the 0-degree The yaw-maneuver is completed about 16 minutes (about 7000 km in flight length on the Earth) in the TRMM case. During the yaw-around, the Precipitation Radar (PR) onboard TRMM continues nominal observation (but data processing is limited to level-1 algorithms). Therefore very dense observation is realized during the yaw-around. Since nearly fixed target (rain echo and surface echo) is observed by different incident angles in a short time, new information can be obtained that cannot be obtained nominal observation. On the incident angle dependency of the sea surface echo, we can avoid the uncertainties comes from the changes in the target. Range profiles of the sea surface echo of different incident angles can be compared with the long-term global average data. The same approach can be used to quantitative estimation of bright band structure such as blurring effect of the off-nadir incident angles. For convective echoes, the non-uniform beam filling (NUBF) effect can be estimated by the different incident angle data and the data which location is slightly offset from the center. More reliable path integrated attenuation (PIA) can be obtained from different incident angle data and the NUBF can be estimated both by the range profiles of surface echo of off-nadir angle bin data with an approach by Takahashi et al. (2006) and their change with the location within a footprint. Two NUBF cases are demonstrated in this paper showing the horizontal sub-footprint size distribution of PIA. The results are confirmed by the consistency of different angle data with slight offset location. In addition, this method is evaluated by the PIA pattern data obtained from densely distributed (because of 180-degree yaw maneuver) data using the method similar to the standard algorithm for TRMM/PR.

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Proceedings Article | 9 October 2008

Development of the DPR algorithms and products for GPM

Misako Kachi, Shuji Shimizu, Naofumi Yoshida, Takuji Kubota, Riko Oki, Toshio Iguchi

Proc. SPIE. 7106, Sensors, Systems, and Next-Generation Satellites XII

KEYWORDS: Radar, Sensors, Satellites, Clouds, Meteorology, Radiometry, Algorithm development, Microwave radiation, Floods, Earth observing sensors

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Proceedings Article | 17 October 2007

Development of the DPR algorithms and products for GPM

Shuji Shimizu, Riko Oki, Misako Kachi, Hiroshi Hanado, Masahiro Kojima, Toshio Iguchi, Kenji Nakamura

Proc. SPIE. 6744, Sensors, Systems, and Next-Generation Satellites XI

KEYWORDS: Radar, Sensors, Satellites, Meteorology, Radiometry, Algorithm development, Microwave radiation, Climatology, Floods, Earth observing sensors

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Proceedings Article | 3 October 2006

Development of spaceborne dual frequency precipitation radar for the global precipitation measurement mission

Shuji Shimizu, Riko Oki, Masahiro Kojima, Toshio Iguchi, Kenji Nakamura

Proc. SPIE. 6361, Sensors, Systems, and Next-Generation Satellites X

KEYWORDS: Radar, Waveguides, Satellites, Control systems, Antennas, Meteorology, Radiometry, Algorithm development, Microwave radiation, Climatology

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Proceedings Article | 21 October 2005

Global precipitation measurement (GPM) mission and dual-frequency precipitation radar (DPR)

Kenji Nakamura, Riko Oki, Toshio Iguchi, Masahiro Kojima

Proc. SPIE. 5978, Sensors, Systems, and Next-Generation Satellites IX

KEYWORDS: Radar, Satellites, Solids, Antennas, Meteorology, Radiometry, Algorithm development, Microwave radiation, Climatology, Systems modeling

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Proceedings Article | 22 December 2004

Backscattering enhancement with a finite beam width for millimeter-wavelength weather radars

Satoru Kobayashi, Simone Tanelli, Toshio Iguchi, Eastwood Im

Proc. SPIE. 5654, Microwave Remote Sensing of the Atmosphere and Environment IV

KEYWORDS: Radar, Polarization, Backscatter, Scattering, Particles, Reflectivity, Multiple scattering, Solids, Antennas, Spherical lenses

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Proceedings Article | 30 April 2003

Validation analysis after the altitude change of TRMM

Shuji Shimizu, Nobuhiro Takahashi, Toshio Iguchi, Jun Awaka, Toshiaki Kozu, Robert Meneghini, Ken'ichi Okamoto

Proc. SPIE. 4894, Microwave Remote Sensing of the Atmosphere and Environment III

KEYWORDS: Radar, Statistical analysis, Signal attenuation, Satellites, Error analysis, Reflectivity, Meteorology, Analytical research, Statistical methods, Atmospheric sensing

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Proceedings Article | 19 August 1998

Simulation of air- and spaceborne radar rain path attenuation estimation using the mirror image radar return

Liang Liao, Robert Meneghini, Toshio Iguchi

Proc. SPIE. 3503, Microwave Remote Sensing of the Atmosphere and Environment

KEYWORDS: Radar, Mirrors, Scattering, Signal attenuation, Laser scattering, Reflectivity, Surface roughness, Computer simulations, Antennas, Meteorology

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Proceedings Article | 19 August 1998

Preliminary test results of a rain rate profiling algorithm for the TRMM precipitation radar

Toshiaki Kozu, Toshio Iguchi, Robert Meneghini, Jun Awaka, Ken'ichi Okamoto

Proc. SPIE. 3503, Microwave Remote Sensing of the Atmosphere and Environment

KEYWORDS: Radar, Signal attenuation, Calibration, Error analysis, Reflectivity, Data processing, Profiling, Meteorology, Algorithm development, Standards development

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