The all-weather, day-and-night imaging capability of synthetic aperture radar (SAR) has become essential for flood monitoring. We have developed and implemented a fully automatic flood detection algorithm using SAR data from Advanced Land Observing Satellite-2 (ALOS-2). The algorithm rapidly processes ALOS-2 and ancillary data (flood simulation, hazard map, and other geographical information) and provides damage information less than an hour after the input data are entered. The algorithm has been operational since 2022 for disaster response users and is still being improved for better accuracy and robustness. During the two years of operation, our algorithm has responded to 15 flood events, demonstrated superior performance, and provided information used in disaster response activities.

This paper evaluates the digital surface model (DSM) generated from satellite stereo imageries that are simulated by the technology of 3-dimensional computer graphics (3D/CG), as one of the preliminary simulations for the future mission in the Japan Aerospace Exploration Agency (JAXA). By using the 3D/CG instead of real satellite imageries, arbitrary conditions of stereo observation, such as the combinations of viewing angles, can be simulated with fewer limitations. Here we validate the effects of the B/H differences in the DSM generations as a first experiment of this approach. The height accuracies of the DSMs, which are derived from simulated stereo imageries of different B/Hs, are compared quantitatively. The result showed that height errors in the city area rapidly increase as the B/Hs are enlarged due to the effect of occlusions around the buildings.

The second-generation global imager (SGLI) was launched in December 2017 onboard the global change observation mission-climate (GCOM-C) and has been observing daily global data in 23 different channels using three sensor units: the visible and near-infrared radiometer with nonpolarization (VNR-NP), one with polarization (VNR-PL), and the infrared scanning radiometer (IRS). The VNR-NP uses a push-broom scanner to observe 11 spectral bands with 250-m and 1-km spatial resolutions. The VNR-PL collects the polarization data for three angles in two spectral bands with a spatial resolution of 1 km by a push-broom scanner. The IRS observes six spectral bands with spatial resolutions of 250 m, 500 m, and 1 km by a whiskbroom scanner. Their geometric processing was one of the technical challenges, where the 23-channel data acquired by the three independent sensors have different geometric characteristics. For their calibration, the imageries of the Advanced Visible and Near-Infrared Radiometer Type-2 (AVNIR-2) were used as the ground control points (GCPs). Their finer resolution, geolocation accuracies, and global distribution made the calibration more detailed. A systematic strategy was conducted in the calibration, which combines the absolute errors from GCPs and the relative errors among different channels. The errors were measured by the image-matching technique between different spectral bands based on their image correlations. As a result, the geolocation accuracies have satisfied the specification of 0.5 pixels (rms) for over six years since launch. This article describes the geolocation approach and the geometric calibration of the SGLI.

This paper evaluates the digital surface model (DSM) derived from high-resolution optical satellite imageries, as one of the preliminary simulations for the future mission of the Japan Aerospace Exploration Agency (JAXA). The DSMs are generated from the imagery pairs of different satellites, i.e., the WorldView-2 and the SkySat, as the simulation of the stereo observation with the constellation of satellites that have different sensor specifications. The results are compared with the ones generated from the conventional imagery pairs of the same satellites. For the preliminary study of environmental monitoring using DSMs generated from satellite imageries, two DSMs of different observing dates on the isolated volcanic island are generated from SkySat stereo imagery pairs. The analysis of the height differences between these two DSMs revealed that it has the potential to detect detailed temporal changes, such as smoke rising from volcanic clacks.

The “Advanced Optical Satellite” (ALOS-3, nicknamed “DAICHI-3”) is the next high-resolution optical mission as a successor of the Advanced Land Observing Satellite (ALOS) in Japan Aerospace Exploration Agency (JAXA), and will be launched in early 2022. The mission objectives of ALOS-3 are (1) to contribute safe and secure social including provision for natural disasters, and (2) to create and update geospatial information. The “wide-swath and high-resolution optical imager” is designed to be achieved the missions, which consists of the panchromatic band with 0.8 m ground sampling distance (GSD) and multispectral six bands with 3.2 m GSD, and the observation swath width is 70 km at nadir. This paper introduces the updated ALOS-3 calibration and validation preparation status at JAXA. As the target accuracy of ALOS-3 standard product, the absolute geometric accuracy is 1.25 m in horizontal and 2.5 m in vertical with GCPs (1 sigma), and the absolute radiometric accuracy is +/ - 10 % for the multispectral band.

The “Advanced Land Observing Satellite-3 (ALOS-3)” is a follow-on satellite of the optical sensors onboard the Advanced Land Observing Satellite (ALOS) in the series of land observing satellites launched by Japan Aerospace Exploration Agency (JAXA). It equips with panchromatic and six-band multispectral optical sensors that have ground resolutions of 0.8 m and 3.2 m respectively while keeping the wide swath of 70 km that is the same as their predecessors onboard the ALOS. The satellite can collect stereo imageries by using a function of large body-pointing up to 60 degrees from the nadir. The digital surface models (DSMs) are generated from stereo imageries as one of the high-level products. This paper reports on plans for the geometric calibration and its derived DSM processing for the ALOS-3 optical imageries.

The “Advanced Optical Satellite” (ALOS-3, nicknamed “DAICHI-3”) is the next high-resolution optical mission as a successor of the Advanced Land Observing Satellite (ALOS) in Japan Aerospace Exploration Agency (JAXA), and will be launched in Japanese Fiscal Year 2021. The mission objectives of ALOS-3 are (1) to contribute safe and secure social including provisions for natural disasters, and (2) to create and update geo-spatial information. The “wide-swath and high-resolution optical imager” is designed to be achieved the missions, which consists of the panchromatic band with 0.8 m ground sampling distance (GSD) and multispectral six bands with 3.2 m GSD, and the observation swath width is 70 km at nadir. This paper introduces the updated calibration and validation plan of ALOS-3 at JAXA. As the target accuracy of ALOS-3 standard product, the absolute geometric accuracy is 1.25 m in horizontal and 2.5 m in vertical with GCPs (1 sigma), and the absolute radiometric accuracy is +/−10 % for multispectral band.

The “Advanced Land Observing Satellite-3 (ALOS-3)” is a follow-on mission of the optical sensors onboard the Advanced Land Observing Satellite (ALOS) in the series of land observing satellites launched by Japan Aerospace Exploration Agency (JAXA). It equips with a panchromatic optical sensor that has a ground resolution of 0.8 m and a multispectral optical sensor that has six spectral bands at a ground resolution of 3.2 m, while keeping the wide swath of 70 km that is the same as the preceding optical sensors onboard the ALOS. The satellite will acquire stereo imageries by using a function of large body-pointing up to 60 degrees from nadir. The digital surface model (DSM) will be generated from the stereo imageries as one of the high-level products. This paper reports on an overview of the geometric calibration and its derived DSM generation for the ALOS-3 optical imageries.

The "Advanced Optical Satellite" is a follow-on satellite of the optical sensors onboard the Advanced Land Observing Satellite (ALOS) and is called "ALOS-3" in the series of land observing satellites launched by Japan Aerospace Exploration Agency (JAXA). It will achieve approximately three times higher ground resolution of 0.8 m while keeping the wide swath of 70 km as compared with its preceding Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) onboard the ALOS. Though the sensor does not equip with multiple sensor-units which achieve the full-time along-track stereo observation like the PRISM, it will be able to acquire stereo imageries by using a large body-pointing capability within 60 degrees from nadir. The digital surface model (DSM) is expected to be processed from the stereo imageries as one of the high-level products in the ALOS-3 mission. This paper reports on a pre-launch simulation of the DSM generation from the ALOS-3 stereo imageries.

The “Advanced Optical Satellite” (nicknamed “ALOS-3”) is the next high-resolution optical mission as a successor of the Advanced Land Observing Satellite (ALOS) in Japan Aerospace Exploration Agency (JAXA), and now conducting the Critical Design Review (CDR) phase. The mission objectives of ALOS-3 are (1) to contribute safe and secure social including provisions for natural disasters, and (2) to create and update geo-spatial information. The “wide-swath and high-resolution optical imager” is designed to be achieved the missions, which consists of the panchromatic band with 0.8 m ground sampling distance (GSD) and multi-spectral six bands with 3.2 m GSD, and the observation swath width is 70 km at nadir. In addition, the satellite has the body pointing capability within 60 deg. from nadir that will contribute to an emergency observation. In this study, the simulated images generation is introduced to investigate the feasibility of the missions as a part of pre- flight phase study.

In 2016 we first completed the global data processing of digital surface models (DSMs) by using the whole archives of stereo images derived from the Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) onboard the Advanced Land Observing Satellite (ALOS). The dataset has unprecedented 5 m grid spacing utilizing the optical stereo images in 2.5 m resolution while the accuracy was confirmed at 5 m (rms) in vertical and also at 5 m (rms) in horizontal. One year later from the first release of the dataset we updated it with additional calibrations of PRISM interior parameters to eliminate slight systematic height errors which appeared along track. In this paper we present additional updates of the dataset with applying the semiglobal matching (SGM) for the DSM generation as well as corrections of mask data for sea areas.

A new global digital surface model (DSM) dataset using the archived data of the Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) onboard the Advanced Land Observing Satellite (ALOS) has been completed on March 2016 by Japan Aerospace Exploration Agency (JAXA) collaborating with NTT DATA Corp. and Remote Sensing Technology Center, Japan. This project calls “ALOS World 3D” (AW3D), and the dataset consists of the global DSM with 0.15 arcsec. pixel spacing (approx. 5 m mesh) and ortho-rectified PRISM images. JAXA is also processed the global DSM dataset with 1 arcsec. spacing (approx. 30 m mesh) calls “ALOS World 3D 30 m mesh” (AW3D30) based on the AW3D DSM, and released it free of charge on May 2016 as version 1. A weakness of the AW3D30 DSM is remaining void pixels due to cloud covers. This paper describes the AW3D30 partially updates by complementing void pixels using other global digital elevation models, and reports a validation result.

In March, 2016 we first completed the global data processing of digital surface models (DSMs) by using the whole archives of stereo images derived from the Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) onboard the Advanced Land Observing Satellite (ALOS). The dataset has unprecedented 5 m grid spacing utilizing the original stereo images in 2.5 m resolution while its target accuracy was set to 5 m (rms) in vertical and also 5 m (rms) in horizontal. After the first global validation was completed, we detected slight systematic relative height errors in the DSM dataset. This paper reports on the dataset updates which eliminate the errors with an additional calibration of the PRISM physical sensor model.

One of the fundamental issues in the generation of digital surface models (DSMs) from optical stereo imageries is the noise reduction on the low correlation areas. We apply the non-local means filtering to the DSM derived from Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) onboard Advanced Land Observing Satellite (ALOS) with modifying the original algorithm so that it can appropriately remove the noise while preserving the original resolutions/profiles of the terrain. The results of the filtering are evaluated quantitatively with a reference DSM derived from an airborne LiDAR instrument, as well as qualitatively with visual inspections. The proposed algorithm shows the ability to improve global DSM datasets generated from ALOS PRISM.

The Japan Aerospace Exploration Agency is generating the global digital elevation/surface model (DEM/DSM) and ortho-rectified image (ORI) using the archived data of the Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) onboard the Advanced Land Observing Satellite (ALOS, nicknamed “Daichi”), which was operated from 2006 to 2011. The overview and the processing status of the global DSM/ORI dataset generation project called “ALOS World 3D” (AW3D) is introduced in this paper. It is necessary to consider data processing strategies, since the processing capabilities of the level 1 standard product and AW3D products must be developed both hardware and software to achieve the project aims. The processing strategies and an initial validation of generated DSM dataset are described. As an initial validation results, 4.10 m of height accuracy as root mean square error was confirmed. The generation and distribution of a lower resolution AW3D DSM dataset is also introduced.

Panchromatic Remote-sensing Instrument for Stereo Mapping, one of onboard sensors carried by Advanced Land Observing Satellite, was designed to generate worldwide topographic data with its optical stereoscopic observation. It has an exclusive ability to perform a triplet stereo observation along its track, and collected its derived images all over the world during the mission life of the satellite from 2006 through 2011. We have started a new project which generates global elevation datasets with the image archives since last year. The data is processed in unprecedented 5m grid spacing utilizing the original triplet stereo images in 2.5m resolution. As the number of processed data is growing steadily, a trend of actual data qualities became apparent more. This paper reports on up-to-date results of the quality assessments for the data products as well as some algorithm updates for the processing software.

Panchromatic Remote-sensing Instrument for Stereo Mapping, one of onboard sensors carried by Advanced Land Observing Satellite, was designed to generate worldwide topographic data with its optical stereoscopic observation. The sensor had observed huge amount of stereo images all over the world during the mission life of the satellite from 2006 through 2011. To utilize all these archive data we proceed to generate new global elevation datasets, named `ALOS World 3D', which have finer ground resolution and higher accuracy than the existing ones e.g., Shuttle Radar Topography Mission data. This paper briefly reports on latest algorithms for the production of the global datasets with preliminary results of its early operations. The accuracies and error characteristics of the datasets are analyzed and discussed by the comparison with reference data on various fields.

The special and temporal analysis is a primitive approach in the remote sensing field. The Advanced Land Observing Satellite (ALOS, nicknamed `Daichi') has been operated very well from 2006 to 2011, and mainly observed global land region with fine resolutions by three sensors i.e. an L-band Synthetic Aperture Radar called PALSAR and two optical instruments called PRISM and AVNIR-2. They have been captured actual Earth's surface in to this era. As the ALOS follow-on mission, ALOS-2 is succeeded to the Radar mission of ALOS and carried on the state-of-the-art L-band SAR called PALSAR-2, and will be launched in JFY2013. On another front, the ALOS follow-on optical mission has not been approved by the government. This study describes to generate the simulated images and their evaluations for the next land observation satellite. In JAXA, the optical imager that has capabilities of a finer resolution, wide observation swath width, and stereo function are expected as the PRISM follow-on instrument tentatively called PRISM-2. To identify hardware specifications of PRISM-2 as well as utilization capability of acquired data, simulated images were generated with various parameters using the airborne line scanner, and the image quality, interpretation capacity, and the height estimation accuracy by stereo pair images were evaluated.

Panchromatic Remote-sensing Instrument for Stereo Mapping, one of onboard sensors carried by Advanced Land Observing Satellite, was designed to generate worldwide topographic data with its stereoscopic, high resolution observation. The global digital surface models are expected to be generated by utilizing the archives of the stereo images observed during more than five years of the satellite mission. The operation to generate the digital surface model should be full-automatic so that we can process a huge amount of archived stereo images consisting of more than one million scenes on global land areas. One of the most challenging tasks in the full-automatic process is the masking/discarding of outlier areas covered with water, snow, cloud, etc. This paper briefly reports on the preliminary algorithms of the full-automatic process, including the masking/discarding of outlier areas, to generate the global digital surface models.

The Advanced Land Observing Satellite (ALOS, nicknamed `Daichi') was launched on January 2006, and has operated very well. However, its operation moved to the low load mode (LLM) since April 22, 2011, and was subsequently followed by an official termination on May 12, 2011. Notwithstanding, approx. 6,500,000 scenes of archived data covering the entire globe are available to users. Therefore the calibration result is still important information for users. This paper describes calibration results of two optical instruments called PRISM and AVNIR-2 onboard ALOS are summarized during whole mission period. The previous result has been published in 2009, which was explained an overview of calibration and validation plan, and their results at that time. As the updated calibration results, we confirmed 6.1 m (root mean square error, RMSE) for PRISM nadir-looking radiometer and 21.9 m (RMSE) for AVNIR-2 0 deg. pointing of absolute geometric accuracies, and no significant degradation on radiometric accuracy.

Panchromatic Remote-sensing Instrument for Stereo Mapping, one of onboard sensors carried by Advanced Land Observing Satellite, was designed to generate worldwide topographic data with its high resolution and stereoscopic observation. More than six thousand scenes of digital surface model were processed so far from its images in Japan Aerospace Exploration Agency. The areas of processed scenes cover all Japan land areas and some foreign sites for specific research projects. This paper reports on the latest status of the digital surface model scene archives in all Japan land areas and a mosaicking process which combines them into 1°×1° geographic latitude/longitude tiles. The absolute and relative accuracies of mosaicked digital surface model tiles are validated with ground control points and a variety of height reference data including digital surface models produced by airborne light detection and ranging instruments.

The Rational Polynomial Coefficients (RPC) is being widely used for representing the physical sensor models of satellite optical images. The Remote Sensing Technology Center of Japan (RESTEC) has already released the RPC data sets for Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) and Advanced Visible and Near Infrared Radiometer type 2 (AVNIR-2) onboard Advanced Land Observing Satellite (ALOS) with respect to their physical sensor models calibrated by Japan Aerospace Exploration Agency's (JAXA's) Earth Observation Research Center (EORC). Though the RPC data of PRISM/AVNIR-2 have been widely used in public users since the release, the research on them has not been published. This paper reports on the processing method and accuracy assessment results of the RPC data for PRISM/AVNIR-2. Their adjustment models to ground control points are presented with some experimental results as well as the triangulation accuracies and DSM generations for PRISM.

Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) carried by Advanced Land Observing Satellite (ALOS) was designed to generate worldwide topographic data with its high resolution and stereoscopic observation. According to this aim, we developed the software of generating Digital Surface Model (DSM) data. Following the accumulations of PRISM stereoscopic observation data during over five year operations, the capabilities of the matching-algorithm for stereo images, as well as the characteristics of processed DSMs, were widely validated. This paper reports on the latest validation results, archiving status, and the mosaicking results of the DSM.

Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) carried at Advanced Land Observing Satellite (ALOS) was designed to generate worldwide topographic data in respects of its high resolution and stereoscopic land observation. Following accumulations of the on-orbit data since the launch, the characteristics of its sensor geometry and the capabilities to generate the Digital Surface Model (DSM) have been widely validated in Japan Aerospace Exploration Agency. This paper reports on the DSM processing status, over the four-year period of operations, including a mosaicking process and analysis of error characteristics. We especially focused on an occasional waving noise of the DSM caused by an attitude fluctuation of the satellite. Detailed analysis and correction methods on the waving noise are presented in this paper with inspection of satellite attitude data as well.

The Advanced Land Observing Satellite (ALOS, nicknamed ¿Daichi¿) was successfully launched on January 24, 2006, and continues to work very well. In this paper, we introduce the updating calibration results and their time trends of the standard products for two optical instruments onboard ALOS, the Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) and the Advanced Visible and Near Infrared Radiometer type-2 (AVNIR-2). Geometric calibration is important in generating a precise digital surface model (DSM) by a stereo pair image of PRISM. Relative geometric calibration of both PRISM and AVNIR-2 are conducted by evaluating accuracies within one scene and evaluating sensor alignments as absolute calibration. For absolute geometric accuracies, we achieved 7.8 m for nadir-, 8.0 m for forward-, 18.7 m for backward-looking images of PRISM, and 114.2 m for AVNIR-2, respectively.

Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) carried by Advanced Land Observing Satellite (ALOS) was designed to generate worldwide topographic data in respects of its high resolution and stereoscopic observation. Japan Aerospace Exploration Agency's (JAXA's) Earth Observation Research Center (EORC) has widely assessed the on-orbit geometric performance of PRISM sensors since the launch in January 2006. This ongoing activity has generated various geometric performance data over three year on-orbit period of operations. EORC also performed the data analysis of digital surface model (DSM) derived from these geometric performance data. The detailed characteristics of triangulations for PRISM stereo-geometry were evaluated by ground control points (GCPs) and height accuracies of the DSM were also evaluated from the comparison with reference DSM data sets. DSMs are being routinely processed on a scene basis at EORC and mosaicked for global standardized datasets. The preliminary result of the mosaicking process was given with their accuracy analysis.

The Advanced Land Observing Satellite [(ALOS); nicknamed ldquoDaichirdquo] was successfully launched on January 24, 2006, and it continues to work very well. This paper describes the calibrations of two optical instruments onboard ALOS, which are the Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) and Advanced Visible and Near-Infrared Radiometer type 2 (AVNIR-2). PRISM consists of three panchromatic radiometers and is used to derive a digital surface model (DSM) with high spatial resolution, which is an objective of the ALOS mission. AVNIR-2 has four radiometric bands from blue to near infrared, which are used for investigating regional environment issues such as land-use and land-cover classifications, and disaster monitoring. In this paper, we introduce the calibration and validation plan, methodologies, accuracy assessments of the standard products, image quality evaluations for PRISM and AVNIR-2, and their results. Geometric calibration is important in generating a precise DSM by a stereo pair image of PRISM. The relative geometric calibrations of both PRISM and AVNIR-2 are conducted by evaluating accuracies within one scene and evaluating sensor alignments as absolute calibration. For absolute geometric accuracies, we achieved 8.1 m for nadir-looking images and 9.3 m for forward- and backward-looking images of PRISM; we also achieved 114.2 m for AVNIR-2. PRISM is also radiometrically calibrated both relatively and absolutely. PRISM relative radiometric calibration is accomplished by using acquired images over homogeneous targets, such as oceans, deserts, ice, and snow areas, as well as nighttime observation. Simultaneously observed images with calibrated AVNIR-2 are used for absolute radiometric calibration by cross-calibration. The absolute radiometric accuracy of the PRISM nadir-looking radiometer is similar to that of AVNIR-2.

The Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) carried by the Advanced Land-Observing Satellite was designed to generate worldwide topographic data with its high-resolution and stereoscopic observation. For this objective, the on-orbit geometric performance of PRISM sensors has been widely assessed and calibrated since the launch in January 2006 as an activity of the calibration and validation team of the Japan Aerospace Exploration Agency's Earth Observation Research Center. This ongoing activity has generated various geometric performance data over two and a half years of on-orbit operation. A suite of geometric model parameters was calibrated to express the geometric characteristics of the PRISM sensors. These include static interior parameters (charge-coupled device camera parameters) and dynamic exterior parameters (orbit data, attitude data, and sensor alignment). The interior parameters were calibrated using test-field self-calibration with test sites of dense ground control points (GCPs). The exterior parameters were calibrated by adaptive orientation with test sites of worldwide GCPs. These parameters are correlated to the direct geolocation accuracy of the PRISM sensors and are monitored and validated to maintain performance. The performance of the digital surface model (DSM) derived from these geometric model parameters was analyzed. The detailed characteristics of the triangulation results were analyzed by GCPs, and the height accuracy was evaluated based on comparisons with high-accuracy high-resolution reference DSM data sets derived from Lidar and aerial photo matching of various terrain features.

The Advanced Land Observing Satellite (ALOS, nicknamed "Daichi") was successfully launched on January 24, 2006 and it continuously working very well. This paper introduces the updated results of calibration for two optical sensors of ALOS i.e. the Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) and the Advanced Visible and Near Infrared Radiometer type-2 (AVNIR-2). PRISM consists of three panchromatic radiometers, and is using to derive a digital surface model (DSM) that is topography and terrain height information with high spatial resolution. Therefore, geometric calibration is important in generating a highly accurate DSM by stereo pair image of PRISM. The radiometric calibration is also important for PRISM as well as AVNIR-2. This paper describes the updated results of geometric and radiometric calibrations and image quality evaluation of PRISM and AVNIR-2 in the operational phase, which are including stability or time trend of accuracies during 2.5 years since launch the ALOS.

The algorithm for generating digital surface model (DSM) from PRISM was developed for Earth Observation Research Center in Japan Aerospace Exploration Agency (EORC/JAXA). The geometric model stability and accuracy of PRISM have been calibrated for the DSM generation. The interior parameters of PRISM geometry are CCD alignment models and calibrated by the self-calibrations with dense ground control points (GCPs). The exterior parameters of PRISM geometry consist of the orbit data measured by the onboard GPSR, the satellite attitude data measured by the onboard star tracker and sensor alignment models. Those exterior parameters have been calibrated with GCPs as well. The accuracies of DSM generated from those PRISM geometric models are presented with the results of the comparison with high accuracy and high resolution reference DSM data sets derived from LiDAR and aerial photo at the various terrain features.

The Advanced Land Observing Satellite (ALOS, the nickname is “Daichi”) was successfully launched on January 24th, 2006, and it continuously working very well. This paper introduces the updated results of calibration for two optical sensors of ALOS i.e., the Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) and the Advanced Visible and Near Infrared Radiometer type-2 (AVNIR-2). PRISM consists of three panchromatic radiometers, and is used to derive a Digital Surface Model (DSM) with high spatial resolution, which is also an objective of the ALOS mission. The geometric calibration is important in generating a highly accurate DSM by stereo pair image of PRISM. The radiometric calibration is also important for PRISM as well as AVNIR-2. This paper describes the results of geometric and radiometric calibrations for PRISM and AVNIR-2 in the operational phase after initial calibration phase, which are including methodology of analysis and experiment, update parameters related to the absolute accuracy, stability evaluations during one and half years after the launch, and accuracy assessment plan during mission life of the ALOS.

PRISM carried at ALOS satellite is expected to generate worldwide topographic data in respects of its high resolution and stereoscopic observation. The algorithms for generating Digital Surface Model (DSM) and Ortho-Rectified Image (ORI) have been developed for those objectives in Earth Observation Research Center / Japan Aerospace Exploration Agency (EORC / JAXA). During first one year following the successful ALOS launch, the capabilities of the algorithm have been widely tested. In this paper, the performance analysis intermediate results of DSM and corresponding ORI processing are described. First, the geometric model analysis of PRISM sensor is presented with the experimental results of the orientation processing. Then, the performance analysis of DSM and ORI generated with the PRISM geometric model is presented. The accuracy assessment results of generated DSM are presented from the comparison with high accuracy and high resolution reference DSM data sets of LiDAR DSM and Aerial Photo DSM. The accuracy assessment results of generated ORI are presented from the comparison with GCP.

This paper introduces the updated plans of calibration and validation for two optical sensors i.e., the Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) and the Advanced Visible and Near Infrared Radiometer type-2 (AVNIR-2), which are to fly on the Advanced Land Observing Satellite (ALOS). PRISM consists of three panchromatic radio- meters, and is used to derive a Digital Elevation Model (DEM) or a Digital Surface Model (DSM) with very high spatial resolution, which is also an objective of the ALOS mission. The geometric calibration is important in generating a highly accurate DEM by stereo pair images of PRISM. The radiometric calibration is also important for PRISM as well as AVNIR-2. The relative radiometric calibration will be done using acquired images over homogeneous targets such as the nighttime observation, ocean, deserts, and ice lands. The absolute radiometric calibration will be carried out by vicarious calibration and the cross calibration using with calibrated satellite images i.e., ASTER, IKONOS etc. In this paper, test simulations of calibration tools are described using current satellite images. Keywords-ALOS; PRISM; AVNIR-2; Calibration; Validation.

The Advanced Land Observing Satellite (ALOS) has been developed to contribute to the fields of mapping, precise land coverage observation, disaster monitoring, and resource surveying and will be launched in 2005. The Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) carried at ALOS satellite is expected to generate worldwide Digital Maps in respects of its high resolution and stereoscopic observation. The development and evaluation of the software for generating digital surface model (DSM), based on this aim of ALOS operation, is now undertaking for the purpose of equipping the system which producing DSM semi-routinely in the Earth Observation Research and Application Center (EORC). In this paper, the statuses of pre-launch simulations and DSM assessment plans are described. PRISM consists of three panchromatic radiometers for forward, nadir, and backward views and acquires each image in the same orbit at almost the same time. It enables to generate more precision DSM frequently than usual stereoscopic observations. For this specific stereo image configuration, the triplet images matching algorithm is applied for the DSM generation. To evaluate the algorithm, three line scanner (TLS) data is used as the PRISM simulation data. The DSM generation using the JERS-1 OPS stereo images is being performed as the operational simulation. The basic functions of the software such as bundle adjustment, DSM mosaic, mask operation, etc. are evaluated in those simulations. The accuracy assessment of generated DSM is planned to be performed using the LIDAR DSM data, SRTM data, GCP etc.

The Advanced Land Observing Satellite (ALOS) has been developed to contribute to the fields of mapping, precise land coverage observation, disaster monitoring, and resource surveying. The Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM), carried on ALOS satellite is expected to generate worldwide Digital Maps in respects of its high resolution and stereoscopic observation. The development and evaluation of the software for generating Digital Elevation Model (DEM), based on this aim of ALOS operation, is now undertaking for the purpose of equipping the system which producing DEM semi-routinely in the Earth Observation Research and application Center (EORC). In this paper, the software's outline of functions, the algorithm and the current status of its development and evaluation are described. PRISM consists of three panchromatic radiometers for forward, nadir, and backward views and acquires each image in the same orbit at almost the same time. It enables to generate more precision DEM frequently than usual stereoscopic observations. For this specific stereo image configuration, the triplet images matching algorithm is applied for the DEM generation. To evaluate the algorithm, Three Line Scanner (TLS) data is used as the PRISM simulation data and the Lider DEM is used as the reference data. The absolute accuracy of generated DEM is estimated in this simulation

The Panchromatic Remote sensing Instrument for Stereo Mapping (PRISM) sensor that will be carried on the Advanced Land Observing Satellite (ALOS) includes creation of digital elevation maps as one of its purposes. PRISM is capable of high spatial resolution and along-track stereoscopic observation. In order to provide software to create a Digital Elevation Model (DEM) semi-routinely at the Earth Observation Research Center (EORC), development of a DEM generation algorithm and software was carried out. The authors considered the basic function of DEM generation software, various processing algorithms for DEM generation were examined, and a trial production and evaluation which used test data was performed This paper reports the resulting processing method, and evaluation of results, of DEM generated from test data consisting of the nadir and forward images from JERS-1/OPS.