This PDF file contains the front matter associated with SPIE Proceedings Volume 7807, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.

The Clouds and Earth's Radiant Energy System (CERES) uses four instruments onboard two spacecraft to make measurements of the earth's reflected shortwave and emitted longwave radiation, which constitute two components of earth radiation budget. Flight Models 1 and 2 (FM1, FM2) are onboard the TERRA spacecraft and Flight Models 3 and 4 (FM3, FM4) are onboard the AQUA spacecraft. The measurements are made using three radiometric sensor channels on each instrument- shortwave channel (0.3-5 microns), window channel (8-12 microns) and total channel (0.3-200 microns). This paper describes the process of obtaining the estimates of the spectral response functions of the three sensor channels using pre-launch measurements. The shortwave spectral response function (0.3-2 microns) for the shortwave channel as well as the shortwave region of the total channel is obtained through measurements of the components in the optical path. The longwave responses (>2 microns) are obtained using a Fourier Transform Spectrometer (FTS) system. The CERES sensors as well as a reference detector, which is used to account for any measurement or background noise in the system, acquire measurements of the FTS. By the use of various sources and beam-splitters in the spectrometer, the entire spectral range of the broadband total channel is covered. The spectral estimates are obtained in smaller, overlapping bands, which are then tied together appropriately to obtain the end-to-end spectral response function for each of the sensors for all CERES instruments.

The Aerosol Polarimetry Sensor (APS) is the primary Earth observing instrument of the Glory Mission. It is expected to launch into space in the 4th quarter of 2010. This paper summarizes results from the APS ground-testing, completed in 2009. Ground testing established that the instrument meets or exceeds performance requirements: SNR, dynamic range, radiometric accuracy, polarimetric accuracy, response vs. scan angle, boresight co-alignment, and calibration sources accuracy. The APS demonstrated excellent performance stability during sensor and spacecraft level testing over a wide range of environmental conditions. The APS will be a significant improvement over existing sensors that measure aerosols from space. It will provide the scientific community with new information about the distribution and properties of aerosols around the globe. Scientists will use APS data to estimate the radiative forcing imposed on the Earth by aerosols, to assess the effects of aerosols on the Earth's climate.

The design of an optical system typically involves a sensitivity analysis where the various lens parameters, such as lens spacing and curvatures, to name two parameters, are (slightly) varied to see what, if any, effect this has on the performance and to establish manufacturing tolerances. A similar analysis was performed for the VIIRS instruments polarization measurements to see how real world departures from perfectly linearly polarized light entering VIIRS effects the polarization measurement. The methodology and a few of the results of this polarization sensitivity analysis are presented and applied to the construction of a single polarizer which will cover the VIIRS VIS/NIR spectral range.

The telescope for the Operational Land Imager (OLI) completed alignment in July, 2009. Environmental testing was completed in September, 2009. This paper presents the as-designed and as-built performance of the telescope and demonstrates compliance to the OLI requirements. Performance parameters to be discussed include: Effective Focal Length, Modulation Transfer Function, Throughput, Polarization and Pointing.

Ball Aerospace has field tested an Engineering Design Unit (EDU) of a Low Light Imager (LLI) instrument capable of high dynamic range imaging in the Visible to Near Infrared (VNIR) wavelength range. The instrument design is wellsuited to imaging scenes at low illumination levels or with radiance levels spanning a high dynamic range, including night scenes with clouds or anthropogenic light sources, and scenes that span the earth's terminator. A novel operating mode autonomously sets gains individually for each pixel and continuously updates the settings. Utilizing this scheme, the LLI EDU achieves a measured dynamic range > 10⁷ in each image pixel of a scene. The upper and lower ends of the LLI dynamic range enable imaging of scenes illuminated by full sunlight or by a quarter moon only, as well as terminator scenes that span the two. The modular instrument configuration facilitates designs with different total Fields of View, including a three-module design with a cross-track FOV of 113 degrees. Testing and validation performed on the EDU include stray light testing, calibration and acquisition of ground images from an airborne platform. Radiometric test results demonstrate compliance with all radiometric requirements for the day/night imager for the National Polar Orbiting Environmental Spacecraft and Sensor (NPOESS) program.

The Landsat Data Continuity Mission (LDCM) project at the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) is supervising the manufacture and calibration of the Operational Land Imager (OLI) satellite instrument by Ball Aerospace in Boulder, Colorado. As part of that oversight function, the project is preparing a set of radiometers to monitor long-term changes (if any) in the radiance from the integrating sphere used for the radiance calibration of the OLI instrument. That sphere, calibrated at the National Institute of Standards and Technology (NIST), serves as an artifact for establishing traceability of the OLI radiance calibration to SI units, that is, to the radiance scale at NIST. This paper addresses the characterization of two Analytic Spectral Devices (ASD) Fieldspec spectrometers that are part of the NASA/NIST program to validate radiometric reference standards in the LDCM project. In particular, we report on a series of measurements at NIST to determine the ASD spectrometers' long-term stability. Along with other radiometers, the ASDs will be used in the monitoring of changes in the OLI reference sphere from its calibration at NIST to its use in the calibration of the OLI satellite instrument. The ASD stability measurements will continue through the conclusion of the calibration of OLI.

We describe an absolute, spectrally tunable, detector-based broad-band radiometric calibration source whose uncertainties in spectral radiance may approach those of reference detectors, on the order of 0.1 % (k=1). This uncertainty in the spectral radiance of the source is a factor of two lower than the current uncertainty in radiance sources disseminated by the National Institute of Standards and Technology, USA (NIST). These low uncertainties in radiance calibration sources are required for satellite sensors supporting climate change missions. For example, the uncertainty requirements for the Climate Absolute Radiance and Refractivity Observatory (CLARREO) sensor are approximately 0.2 % (k=1) in the silicon range. The conceptual framework of the source, characterization and radiance validation data and trending of the source radiance over time are described.

The Optical Technology Division of the National Institute of Standards and Technology (NIST) provides reference measurements of specular and diffuse reflectance of materials, including measurements that provide traceability for diffuser plaques that are used as onboard calibration standards in remote sensing. We are developing new instrumentation that will enable angle-resolved Bidirectional Reflectance Distribution Function (BRDF) measurements using a supercontinuum fiber laser-based source and a tunable monochromator. A significant improvement in optical power density at the specimen over that of lamp-based sources is expected. We present an overview of the source design and evaluation, including the predicted impact of supercontinuum sources on our next generation of BRDF measurement instrumentation.

The Clouds and Earth's Radiant Energy System (CERES) scanning thermistor bolometers measure earth-reflected solar and earth-emitted longwaveradiances, at the top- of-the-atmosphere. The bolometers measure the earthradiances in the broadband shortwave solar (0.3-5.0 microns) and total (0.3->100 microns) spectral bands as well as in the 8->12 microns water vapor window spectral band over geographical footprints as small as 10 kilometers at nadir. December 1999, the second and third set of CERES bolometers was launchedon the Earth Observing Mission Terra Spacecraft. May 2003, the fourth and fifth set of bolometers was launched on the Earth Observing Mission Aqua Spacecraft. Ground vacuum calibrations define the initial count conversion coefficients that are used to convert the bolometer output voltages into filtered earth radiances. The mirror attenuator mosaic (MAM), a solar diffuser plate, was built into the CERES instrument package calibration system in order to define in-orbit shifts or drifts in the sensor responses. The shortwave and shortwave part of total sensors are calibrated using the solar radiances reflected from the MAM's. Each MAM consists of baffle-solar diffuser plate systems, which guide incoming solar radiances into the instrument fields of view of the shortwave and total wave sensor units. The MAM diffuser reflecting type surface consists of an array of spherical aluminum mirror segments, which are separated by a Merck Black A absorbing surface, overcoated with SIOx. Thermistors are located in each MAM plate and the total channel baffle. The CERES MAM is designed to yield calibration precisions approaching .5 percent for the total and shortwave detectors. However, in their first year of operation the Terra and Aqua MAMs showed shifts in their calibrations larger than expected. Shifts of this nature have been seen in other Solar viewing instruments in the past. A possible explanation has attributed the changes to pre-orbit or on-orbit contamination combined with solar ultraviolet/atomic oxygen induced chemical changes to the contaminant during solar exposure. In the subsequent year of operation all instruments begin to stabilize within the .5 percent precision range. In this presentation, the MAM solar calibration procedures will be presented along with on-orbit measurements for the nine years the CERES instruments have been on-orbit. A switch to an azimuth rotation raster scan of the Sun rather than an elevation scan will be discussed. The implementation of a thermal correction to the shortwave channel will also be discussed. Comparisons are also made between the Terra CERES instruments and the Aqua instruments during their MAM solar calibrations and total solar irradiance experimental results to determine how precise the CERES solar calibration facilities are at tracking the sun's irradiance.

PARASOL, launched in December 2004, and after a 5 years mission inside the so-called A-train atmospheric orbital observatory together with Aqua, Aura, Calipso, and Cloudsat, is now flying on a slightly lower altitude and will continue its observation for several months. Evolution with time of the sensor's behaviour is a natural process. A decrease of the radiometric sensitivity has been detected an corrected. Because there is no on-board calibration device, this correction was based on an innovative technique developed using deep convective clouds and their remarkable spectral properties. This operational method has been previously published (Fougnie and Bach, 2007). This evolution, larger for shorter wavelengths, reaches nearly 10% for band 490, and 2% for band 865 after 5 years of mission. This estimation was established for "nadir/zenith" geometrical conditions. This means that it represents the evolution of the central part of the camera's field of view. We generalize here the method and results to other geometric configurations. It was possible to derive a 2D-mapping of the evolution for all the camera's field of view. This result was validated through other methods using different natural targets. The accuracy of the method is evaluated to a few tenth of percents after 5 years.

Validated models describing on-orbit performance of Earth sensing instruments provide understanding of the calibration of the instrument and insight that can be used to guide design choices for future missions. The success of the Cloud Aerosol Lidar with Orthogonal Polarization (CALIOP) launched as part of the CALIPSO instrument suite provides an opportunity to develop validated radiometric and integrated models of the instrument. We present validation of these models with on-orbit data and describe how these models can be used to help define instrument requirements for future active sensing missions that hope to capture both atmospheric and oceanographic properties. While designed for atmospheric returns, CALIOP data includes backscatter from land, ice, and ocean surface and from beneath the ocean surface. A radiometric model describing atmospheric returns that has been validated against CALIOP performance is extended to include ocean subsurface returns. The model output is compared with CALIOP, aircraft lidar measurements, and space-based ocean color measurements. This provides an opportunity to explore the value of space-based lidar measurements to ocean measurements and to identify the impact of laser and detector design choices on the returned lidar signal from the ocean as part of an ongoing effort to investigate oceanographic lidars.

The MODerate resolution Imaging Spectroradiometer flies on board the Earth Observing System (EOS) satellites Terra and Aqua in a sun-synchronous orbit that crosses the equator at 10:30 AM and 2:30 PM, respectively, at a low earth orbit (LEO) altitude of 705 km. Terra was launched on December 18,1999 and Aqua was launched on May 4, 2002. As the MODIS instruments on board these satellites continue to operate beyond the design lifetime of six years, the cumulative effect of the space environment on MODIS and its calibration is of increasing importance. There are several aspects of the space environment that impact both the top of atmosphere (TOA) calibration and, therefore, the final science products of MODIS. The south Atlantic anomaly (SAA), spacecraft drag, extreme radiative and thermal environment, and the presence of orbital debris have the potential to significantly impact both MODIS and the spacecraft, either directly or indirectly, possibly resulting in data loss. Efforts from the Terra and Aqua Flight Operations Teams (FOT), the MODIS Instrument Operations Team (IOT), and the MODIS Characterization Support Team (MCST) prevent or minimize external impact on the TOA calibrated data. This paper discusses specific effects of the space environment on MODIS and how they are minimized.

The Moderate Resolution Imaging Spectroradiometer (MODIS) has 16 thermal emissive bands (TEB) over a spectral range from mid-wave infrared (MWIR) to long-wave infrared (LWIR), using photovoltaic (PV) HgCdTe detectors for bands 20-25 and 27-30 with wavelengths from 3.75μm to 9.73μm and photoconductive (PC) HgCdTe detectors for bands 31-36 with wavelengths from 11.0μm to 14.2μm. A total of 160 individual detectors, 10 per band, are distributed on the short- and mid-wave (SMIR) and LWIR cold focal-plane assemblies (CFPA) with temperature controlled at 83K. The instrument temperature affects the detector response and this effect varies with the detector type. Detector responses from on-orbit calibration and pre-launch measurements have been examined to characterize this effect. Results from this analysis show that, for the PV detectors on the SMIR CFPA, the detector responses (gains) increase with instrument temperature whereas the PC detector responses decrease with the instrument temperature. The calibration impact due to on-orbit changes in instrument temperatures is examined. On-orbit detector offset and nonlinear response characterization obtained from the on-boar blackbody (BB) warm-up and cool-down (WUCD) cycle is discussed. This investigation was performed for both Terra MODIS and Aqua MODIS.

MODIS collects data in both the reflected solar and thermal emissive regions using 36 spectral bands. The center wavelengths of these bands cover the3.7 to 14.24 micron region. In addition to using its on-board calibrators (OBC), which include a full aperture solar diffuser (SD) and a blackbody (BB), lunar observations have been scheduled on a regular basis to support both Terra and Aqua MODIS on-orbit calibration and characterization. This paper provides an overview of MODIS lunar observations and their applications for the reflective solar bands (RSB) and thermal emissive bands (TEB) with an emphasis on potential calibration improvements of MODIS band 21 at 3.96 microns. This spectral band has detectors set with low gains to enable fire detection. Methodologies are proposed and examined on the use of lunar observations for the band 21 calibration. Also presented in this paper are preliminary results derived from Terra MODIS lunar observations and remaining challenging issues.

Calibration of infrared radiometers at cold scene temperatures is very difficult. But high accuracy even at cold temperatures is critical for establishing a climate-quality data record. This paper describes the comparison of radiances from two sensors-the Infrared Atmospheric Sounding Interferometer (IASI) and the Atmospheric Infrared Sounder (AIRS) for cold scenes. We compare thirty-two months of IASI and AIRS data for Dome Concordia, which is on a high plateau in Antarctica and thus provides a source of nearly uniform dry scenes with a temperature range from about 190 K to about 250 K. Located on this plateau is a research station, an operational automated weather station that provides ground truth. The AIRS L1B and IASI L1C radiometric calibrations agree for large spatial and temporal averages of data taken over 32 months at Dome Concordia at the 200 mK level, in spite of large differences in the instrument implementations. However, both AIRS L1B and IASI L1C data show scene-temperature-dependent differences as large as 1K, which appear to be calibration artifacts that are only partially understood. In the case of AIRS L1B spectra, some of the effects will be corrected in the forthcoming release of the L1C data. In addition, the IASI quality flag identifies a disproportionate number of spectra in the 240-250 K brightness temperature range as "low quality". Uncorrected calibration artifacts and quality flag related issues are likely to be of significance for climate applications, where 100 mK absolute accuracy is required. Both effects create sampling biases, which cannot be decreased by massive data averaging. The effects are small compared to the absolute radiometric calibration accuracy requirements of AIRS or IASI, but both will need to be accounted for in the radiometric accuracy analysis of future instruments specifically designed for climate research.

The radiometric and spectral system performance of space-borne infrared radiometers is generally specified and analyzed under strictly cloud-free, spatially uniform and warm conditions, with the assumption that the observed performance applies to the full dynamic range under clear and cloudy conditions and that random noise cancels for the evaluation of the radiometric accuracy. Such clear conditions are found in only one percent of the data. Ninety nine percent of the data include clouds, which produce spatially highly nonuniform scenes with 11μm window brightness temperatures as low as 200K. We use AIRS and IASI radiance spectra to compare system performance under clear and a wide range of cloudy conditions. Although the two instruments are in polar orbits, with the ascending nodes separated by four hours, daily averages already reveal surprisingly similar measurements. The AIRS and IASI radiometric performance based on the mean of large numbers of observation is comparable and agrees within 200 mK over a wide range of temperatures. There are also some unexpected differences at the 200 -500 mK level, which are of significance for climate applications. The results were verified with data from July 2007 through January 2010, but many can already be gleaned from the analysis of a single day of data.

Imagers and Sounders for Low Earth Orbit (LEO) provide fundamental global daily observations of the Earth System for scientists, researchers, and operational weather agencies. The imager provides the nominal 1-2 km spatial resolution images with global coverage in multiple spectral bands for a wide range of uses including ocean color, vegetation indices, aerosol, snow and cloud properties, and sea surface temperature. The sounder provides vertical profiles of atmospheric temperature, water vapor cloud properties, and trace gases including ozone, carbon monoxide, methane and carbon dioxide. Performance capabilities of these systems has evolved with the optical and sensing technologies of the decade. Individual detectors were incorporated on some of the first imagers and sounders that evolved to linear array technology in the '80's. Signal-to-noise constraints limited these systems to either broad spectral resolution as in the case of the imager, or low spatial resolution as in the case of the sounder. Today's area 2-dimensional large format array technology enables high spatial and high spectral resolution to be incorporated into a single instrument. This places new constraints on the design of these systems and enables new capabilities for scientists to examine the complex processes governing the Earth System.

The Advanced Baseline Imager (ABI) will image Earth in 16 spectral channels, including 10 thermal IR (TIR) channels. The instantaneous field of view (IFOV) of each TIR detector element is (56 μrad)². The ABI has an onboard fullaperture blackbody, the Internal Calibration Target (ICT), used in conjunction with deep space looks to calibrate the ABI's TIR channels. The ICT is only observed over a small range of temperatures and at one specific pair of reflection angles from the ABI's two scan mirrors. The sunlit area on Mercury's surface underfills the IFOV's of the ABI's TIR channels, but has a much higher range of characteristic temperatures than the ICT, so its radiation is weighted more strongly toward shorter wavelengths. Comparison of a TIR channel's responses to the ICT and to Mercury provides a sensitive means to evaluate variations in spectral response functions among detector elements, across the ABI's field of regard, and among instruments on different satellites. Observations of Mercury can also verify co-registration among the ABI's atmospheric absorption channels that do not observe features on Earth's surface. The optimal conditions for viewing Mercury typically occur during one or two intervals of a few weeks each year when it traverses the ABI's FOR (-10.5^o < declination < +10.5^o) with an elongation angle from the Sun of at least 20.5^o.

The goal of the Clouds and the Earth's Radiant Energy System (CERES) project is to provide a long-term record of radiation budget at the top-of-atmosphere (TOA), within the atmosphere, and at the surface with consistent cloud and aerosol properties at climate accuracy (Wielicki et al., 1996). CERES consists of an integrated instrumentalgorithm- validation science team that provides development of higher-level products (Levels 1-3) and investigations. It involves a high level of data fusion, merging inputs from 25 unique input data sources to produce 18 CERES data products. Over 90% of the CERES data product volume involves two or more instruments.

This paper describe mechanical design, dynamic analysis, and deployment demonstration of the antenna , and the photogrammetry detecting RMS of inflatable antenna surface, the possible errors results form the measurement are also analysed. Ticra's Grasp software are used to predict the inflatable antenna pattern based on the coordinates of the 460 points on the parabolic surface, the final results verified the whole design process.

The Radiometric Calibration Test Site (RadCaTS) is an automated approach to ground-based vicarious calibration that does not require on-site personnel during the overpass of an airborne or spaceborne sensor. The concept originates as an attempt to increase the amount of ground-based data that are collected throughout the year. All-weather instruments are used to measure atmospheric and surface conditions. The data are used in an automated processing scheme to produce top-of-atmosphere spectral radiance, which are then compared to the sensor under test. RadCaTS has been located at Railroad Valley, Nevada, since 2004, but the concept is applicable to any site that is suitable for vicarious calibration. Railroad Valley was chosen to test the RadCaTS concept because it has been used by the Remote Sensing Group (RSG) for over 15 years and is well understood. This work describes the RadCaTS automated concept, and outlines the automated processing scheme that is used to determine the surface reflectance. A description of the instrumentation used to measure the surface reflectance and atmosphere is presented, followed by a discussion of their placement on the site, and also their calibration. Finally, the RadCaTS ground-based results are compared to those from Aqua and Terra MODIS in 2008, and Landsat 7 ETM+ in 2009.

One way to calibrate space sensors on the visible part of the spectrum is to use acquisitions over Rayleigh scattering for dark surface conditions. Oceanic sites are good candidates because of their behaviour in term of spatial homogeneity and temporal stability. An appropriate selection is consequently required to identify the best oceanic areas. Nevertheless, the knowledge of the surface reflectance of such sites remains a limitation while their stability (and/or homogeneity) is usually not perfect. A previous study (Fougnie et al., 2002) has defined a selection of oceanic sites using one year of SeaWiFS data and regarding their spatial homogeneity and temporal stability. A first characterization of their monthly surface reflectances was derived (seasonal cycle) and used for several years as input for in-flight calibration processes. The major oligotrophic sites are located in North/South Atlantic and Pacific oceans, in Indian ocean, and in the Mediterranean Sea while some other mesotrophic sites were also defined for example in the Gulf of Mexico or Yucatan strait. The goal of this study was to revisit the definition of these sites regarding their spatial homogeneity and to analyze the annual cycle over 9 years of L3B R-2009 SeaWiFS products. Site behaviours are accurately defined with these longer time series, hence new recommendations are drawn for all sites and an updated climatology is proposed to be used for future in-flight calibrations.

The Lunar Calibration program at the U.S. Geological Survey (USGS) in Flagstaff, AZ, provides the radiometric reference of the Moon as a source for calibration at reflected-solar wavelengths. To develop this capability, thousands of multispectral images of the Moon were acquired by the Robotic Lunar Observatory (ROLO) telescope imaging systems. During normal ROLO operations, 10 to 12 different stars were observed up to 15 times each night, primarily to derive atmospheric transmittance corrections for the Moon observations. But additionally, the ROLO telescope sensors are calibrated to the star Vega through a process of reduction of stellar images to absolute irradiances. A study of the ROLO stellar imaging characteristics for this purpose has led to development of an analytic model for the signal contained in the extended point spread function of the image data. This model is then applied as part of the standard data reduction procedures to generate corrections for individual star images. The resulting absolute stellar irradiance measurements allow development of a calibration history for the entire ROLO dataset, and by extension for the lunar models that constitute the lunar radiometric reference. This paper will discuss the image reduction techniques developed for calibration of the ROLO focal plane array sensors, and the implications of this development on the use of the Moon as a calibration reference source.

Though hyperspectral data can provide more information compared with multi-spectral data, the major problem is the high dimensionality which needs effective approaches to extract useful information for practical purpose, and requires large numbers of training samples to meet statistical requirements. The use of Wavelet Transformation (WT) for analyzing hyperspectral data, particularly for feature extraction from hyperspectral data, has been extremely limited. WT can decompose a spectral signal into a series of shifted and scaled versions of the mother wavelet function, and that the local energy variation of a spectral signal in different bands at each scale can be detected automatically and provide some useful information for further analysis of hyperspectral data. Therefore, in this study, WT techniques was applied to automatically extract features from soybean hyperspectral canopy reflectance for LAI estimation; and compared the model prediction accuracy to those based on spectral indices (PCA). 144 samples were collected in 2003 and 2004, respectively in the Songnen Plain at two study regions. It is found that wavelet transforms is an effective method for hyperspectral reflectance feature extraction on soybean LAI estimation, and the best multivariable regressions obtain determination coefficient ( R²) above 0.90 with RMSE less than 0.30 m²/m². As a comparison study, Vegetation Index (VI) method applied in this study, and wavelet transform technique performs much better than VI method for LAI estimation. Further studies are still needed to refine the methods for estimating soybean bio-physical/chemical parameters based on WT method.

A new airborne Directional Polarimetric Camera (DPC) was developed to retrieve aerosol optical and microphysical properties over urban with high spatial resolution, dealing with the apportionment of sources and controls on air quality in the city. The instrument is a Polarization and Directionality of Earth's Reflectance (POLDER) type polarized camera with significant improvement in the space resolution realizing monitoring aerosol emission and absorption sources like megacities in China. This paper describes the DPC instrument characteristics, instrument calibration, and the flight experiment in the Delta Peal Region of China.

The system structure and development scheme for the simulation of spaceborne microwave scatterometer are presented based on systematically reviewing and summarizing the related previous investigations and the wind measurement rationale of scatterometer, in combination with the consideration of current application requirement of China. Subsequently, as an example, a scatterometer simulation system of HY-2 is developed by using the object-oriented programming method. Taking the parameters for HY-2 as input, the simulation experiments of wind field retrieval for conically scanning scatterometer with co-polarizations are conducted by using the simulation platform designed in this paper.

Spaceborne laser rangefinder is one of the main payloads in earth observation satellites and lunar satellites. In this paper, the ranging sensitivity and accuracy of the spaceborne laser rangefinder have been discussed. And a photon counting detected mode is recommended to improve the rangefinder's sensitivity and the accuracy. A future laser rangefinder system has been designed and it's proved to be available by the test of the prototype.

In this paper, we present an overall description of the newest Chinese airborne SAR mapping system CASMSAR, which is developed by a group led by Chinese Academy of Surveying and Mapping (CASM). Since CASMSAR is equipped with two independent high-resolution SAR sensors (X-band and P-band), it allows the integration of interferometric and fully polarimetric functions. Another novel feature of CASMSAR is the software control of system monitoring and flight navigation display, which makes the whole system very intelligent and operational. The data processing software systems of CASMSAR consists of five subsystems. CASMSAR works in several modes. The most important two of them are used for mapping in scale of 1:10,000 and 1:50,000. Initial data were acquired during several testing flight campaigns in last year, and experimental results have proved that the system works well and the performance is better than expectation.

Hyperspectral remote sensing is a very useful technology for the applications of land and resources area. Although its advantages have already been demonstrated by some applications based on limited data, the data source is still an obvious "bottleneck" for the development of hyperspectral remote sensing applications. The Ministry of Land and Resources of China hence decides to develop a hyperspectral satellite to solve this problem. This paper introduces the designing and construction of the ground hyperspectral data processing system for this satellite including its framework designing, its prototype system development, as well as two geological applications. Mineral mapping and oil and gas detection applications based on the prototype system have both demonstrated the validity and efficiency of the whole system. Mineral mapping application based on simulated space-borne hyperspectral data with different sensor parameters can also provide suggestions for the configuration of sensor parameters.

The near-simultaneous observations from Moderate Resolution Imaging Spectroradiometer (MODIS) and Atmospheric Infrared Sounder (AIRS) sensors on-board the Aqua spacecraft provide a good opportunity to track the relative calibration stability of both sensors over their entire mission. The AIRS is a hyper-spectral sensor with a spectral resolution of around 5 nm that covers the spectral range of most MODIS thermal emissive bands (TEB) except for a few small gaps. The simulated MODIS radiances can be derived by convolving AIRS spectral measurements with MODIS relative spectral response functions. Using spatially collocated pixels, the differences between MODIS observed and AIRS simulated brightness temperatures are computed for most MODIS TEB at various scan angles within ±49.5 degree of the nadir position. Two regions of different scene temperatures are selected: the central Atlantic Ocean and the Dome C at Antarctica. The trending of the MODIS - AIRS brightness temperature differences (BTD) is derived for years 2003- 2008. Results show that the magnitudes of the BTD are spectral band dependent. The values of BTD are generally less than ± 0.5K for most TEB with a few exceptions. For band 27, the BTD are about -1.2 K over the Dome Concordia and about -3.0 K over the northern Atlantic Ocean. Bands 35 and 36 have BTD about +1.0 K over the Atlantic Ocean. The trending results show that the BTD changes over a six-year period are less than 0.3 K for all calculable MODIS bands, and are slightly larger at large scan angles than those near nadir. Our results are consistent with previous studies.

The Visible Infrared Imaging Radiometer Suite (VIIRS) is one of the instruments included in the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP), which is a joint mission between NASA and the NPOESS Integrated Program Office (IPO). The NPP provides a bridge between the current Earth Observing System (EOS) and future NPOESS missions by testing the pre-operational on-orbit system and providing risk reduction for key NPOESS instruments. The VIIRS exploits design concepts of advanced sensors, such as the MODerate Resolution Imaging Spectroradiometer (MODIS), and development of data products on the NASA EOS. It is designed to provide continuity of global observations of land, ocean, cloud, and atmospheric parameters, called Environmental Data Records (EDRs), for real-time meteorological operations and long-term climate change research. This paper provides a brief overview of the VIIRS instrument on-orbit radiometric calibration and characterization activities supported by the NASA NPP Instrument Calibration and Support Element (NICSE). The NICSE is part of the Science Data Segment (SDS) within the NASA NPP program. This paper focuses on the capability and responsibility of NICSE, the tool development for post-launch calibration, and activities to assess sensor performance through the use of its On-board Calibrators (OBCs), as well as to independently verify the quality of VIIRS Sensor Data Records (SDRs).

MODIS thermal emissive bands (TEB) are calibrated on-orbit via its on-board blackbody (BB) and observations through its space view (SV) port. For Terra MODIS, the BB temperature is nominally controlled at 290K. Periodically, a BB warm-up and cool-down (WUCD) process is scheduled and executed, during which the BB temperatures vary from approximately 272K, the instrument ambient temperature, to 315K. The on-board BB temperatures are monitored, on a scan-by-scan basis, using a set of 12 thermistors uniformly embedded in the BB panel. These thermistors were characterized pre-launch and are traceable to the NIST temperature standards. Using more than 10 years of on-orbit measurements, this paper reports Terra MODIS BB performance in terms of its temperature uniformity and stability. On-orbit characterization is made when the BB is operated under the same or different configurations and conditions. In this study, the variations of BB temperatures from its 12 individual thermistors are analyzed scan-by-scan in order to assess its short-term stability and uniformity. To illustrate the long-term stability over the entire mission, only the granule averaged BB temperatures are used. Results from this study will provide useful information for future missions and sensors, such as NPP VIIRS and LDCM TIRS, in support of their on-board BB design, operation, and performance assessments.

The Moderate Resolution Imaging Spectroradiometer (MODIS) has been operating on both the Terra and Aqua spacecraft for over 10.5 and 8 years, respectively. Over 40 science products are generated routinely from MODIS Earth images and used extensively by the global science community for a wide variety of land, ocean, and atmosphere applications. Over the mission lifetime, several versions of the MODIS data set have been in use as the calibration and data processing algorithms evolved. Currently Version 5 MODIS data is the baseline Level-1B calibrated science product. The MODIS Characterization Support Team (MCST), with input from the MODIS Science Team, developed and delivered a number of improvements and enhancements to the calibration algorithms, Level-1B processing code and Look-up Tables for the Version 6 Level-1B MODIS data. Version 6 implements a number of changes in the calibration methodology for both the Reflective Solar Bands (RSB) and Thermal Emissive Bands (TEB). This paper describes the improvements introduced in Collection 6 to the RSB and TEB calibration and detector Quality Assurance (QA) handling.