Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472381
R. Hardesty, J. Intrieri
Characterization of wind structure in the marine boundary layer is important for understanding the processes affecting ocean-atmosphere exchange of heat, moisture and momentum, marine stratus formation and dissipation, and emission and scattering of electromagnetic radiation from the ocean surface. Although wind information in the lower boundary layer can be obtained from balloons, anemometers mounted on ship masts, and/or radar wind profilers, Doppler lidars offer the capability of interrogating a large area segment of the marine layer from a single location with high vertical and moderate horizontal spatial resolution. Application of Doppler lidar to marine studies was first demonstrated by Banta et al. (1993), who used lidar wind measurements to illustrate the temporal and spatial evolution of the sea breeze near Monterey, CA. The present authors extend the applications to include measurements of vertical motion for better understanding of stratocumulus cloud breakup, as well as wind field characterization and the effect of winds on the radar scattering signal from the ocean surface. They also describe a new, container-mounted lidar system specifically designed for shipboard wind measurements.<>
{"title":"Doppler lidar measurements of wind and turbulence in the marine boundary layer","authors":"R. Hardesty, J. Intrieri","doi":"10.1109/COMEAS.1995.472381","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472381","url":null,"abstract":"Characterization of wind structure in the marine boundary layer is important for understanding the processes affecting ocean-atmosphere exchange of heat, moisture and momentum, marine stratus formation and dissipation, and emission and scattering of electromagnetic radiation from the ocean surface. Although wind information in the lower boundary layer can be obtained from balloons, anemometers mounted on ship masts, and/or radar wind profilers, Doppler lidars offer the capability of interrogating a large area segment of the marine layer from a single location with high vertical and moderate horizontal spatial resolution. Application of Doppler lidar to marine studies was first demonstrated by Banta et al. (1993), who used lidar wind measurements to illustrate the temporal and spatial evolution of the sea breeze near Monterey, CA. The present authors extend the applications to include measurements of vertical motion for better understanding of stratocumulus cloud breakup, as well as wind field characterization and the effect of winds on the radar scattering signal from the ocean surface. They also describe a new, container-mounted lidar system specifically designed for shipboard wind measurements.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124890955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472348
Yingyin Zou, Yunhua Zhang, Kangsheng Chen
In the remote sensing of the sea surface (temperature, wind speed, wind direction, the height of wave, etc.) by both active and passive remote sensing instruments (SAR, scattermeter, altimeter, radiometer, etc.), the atmosphere (including cloud and rain) has a large influence especially for instruments working at millimeter and submillimeter wavelengths. Solution methods are considered for the radiative transfer equation for a multilayer medium containing scattering layers; for example the invariant imbedding method. The huge amount of calculations and the little flexibility of computer program make this method impracticable. The authors propose a new method for the solution of the RTE of a multilayer medium containing scattering layers such as cloud and rain.<>
{"title":"A new method for solving the RTE of multilayer medium containing scattering layers","authors":"Yingyin Zou, Yunhua Zhang, Kangsheng Chen","doi":"10.1109/COMEAS.1995.472348","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472348","url":null,"abstract":"In the remote sensing of the sea surface (temperature, wind speed, wind direction, the height of wave, etc.) by both active and passive remote sensing instruments (SAR, scattermeter, altimeter, radiometer, etc.), the atmosphere (including cloud and rain) has a large influence especially for instruments working at millimeter and submillimeter wavelengths. Solution methods are considered for the radiative transfer equation for a multilayer medium containing scattering layers; for example the invariant imbedding method. The huge amount of calculations and the little flexibility of computer program make this method impracticable. The authors propose a new method for the solution of the RTE of a multilayer medium containing scattering layers such as cloud and rain.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125030171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472323
J. Goldsmith, S. Bisson
The authors describe two Raman lidar systems that they are developing for the measurement of atmospheric humidity. One, which has been under development for several years, is used for their own studies at Sandia. The Sandia lidar system is housed in two mobile semitrailers, one trailer serving as a mobile laboratory and the other as a support vehicle providing a data acquisition/analysis area. The lidar uses an injection-seeded excimer laser to provide a beam with reduced divergence and spectral bandwidth, operated at 308 nm during both nighttime and daytime. Enhanced dynamic range, for daytime operation in particular, is provided by using photon counting in the narrow field-of-view channel, and analog to digital conversion in the wide field-of-view channel. The second Raman lidar system under development will have a permanent residence at the Department of Energy's ARM (Atmospheric Radiation Measurement program) CART (Cloud and Radiation Testbed) site near Lament, Oklahoma. This system is based on a high-power 355-nm laser beam produced by a frequency-tripled Nd:YAG laser.<>
{"title":"Raman lidar profiling of atmospheric water vapor","authors":"J. Goldsmith, S. Bisson","doi":"10.1109/COMEAS.1995.472323","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472323","url":null,"abstract":"The authors describe two Raman lidar systems that they are developing for the measurement of atmospheric humidity. One, which has been under development for several years, is used for their own studies at Sandia. The Sandia lidar system is housed in two mobile semitrailers, one trailer serving as a mobile laboratory and the other as a support vehicle providing a data acquisition/analysis area. The lidar uses an injection-seeded excimer laser to provide a beam with reduced divergence and spectral bandwidth, operated at 308 nm during both nighttime and daytime. Enhanced dynamic range, for daytime operation in particular, is provided by using photon counting in the narrow field-of-view channel, and analog to digital conversion in the wide field-of-view channel. The second Raman lidar system under development will have a permanent residence at the Department of Energy's ARM (Atmospheric Radiation Measurement program) CART (Cloud and Radiation Testbed) site near Lament, Oklahoma. This system is based on a high-power 355-nm laser beam produced by a frequency-tripled Nd:YAG laser.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125593712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472341
A. I. Kozlov, A. I. Logvin
General equations are considered for detecting radar targets against the land surface. These equations possess properties to give in reflection, in addition to the basic frequency f, the same signals at multiple frequencies. Such targets are referred to as nonlinear. The authors apply the equations obtained to the detection of nonlinear targets. Both continuous and impulse modes of operation are considered. The maximum range of a radar operating in a continuous mode is determined by the equation. Targets having a considerable number of metallic contacts at the second harmonic can be detected even better than those at the first harmonic. Thus, if a radar target located at a distance of 30 m has R.C.S. equal to 10 m2 and is located on a sand soil, then the probability of a false alarm equal to 10/sup -4/ it is selected with the probability of correct detection equal to 10/sup -8/. At the same time nonlinear targets against the sand background at the same probabilities, will be selected at a distance of 300 m.<>
{"title":"Images of radar targets in non-linear scattering of electromagnetic waves","authors":"A. I. Kozlov, A. I. Logvin","doi":"10.1109/COMEAS.1995.472341","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472341","url":null,"abstract":"General equations are considered for detecting radar targets against the land surface. These equations possess properties to give in reflection, in addition to the basic frequency f, the same signals at multiple frequencies. Such targets are referred to as nonlinear. The authors apply the equations obtained to the detection of nonlinear targets. Both continuous and impulse modes of operation are considered. The maximum range of a radar operating in a continuous mode is determined by the equation. Targets having a considerable number of metallic contacts at the second harmonic can be detected even better than those at the first harmonic. Thus, if a radar target located at a distance of 30 m has R.C.S. equal to 10 m2 and is located on a sand soil, then the probability of a false alarm equal to 10/sup -4/ it is selected with the probability of correct detection equal to 10/sup -8/. At the same time nonlinear targets against the sand background at the same probabilities, will be selected at a distance of 300 m.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129521550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472351
E. Kasischke, P. Camille, H. Shugart, L. Bourgeau-Chavez, N. French
Fire is a major disturbance regime for boreal forest and is also a major factor in the exchange of carbon between biotic components and the atmosphere. The occurrence of fire in boreal forests is extensive, and individual fire events typically cover large areas, with fires between 1000 and >1000000 ha in size accounting for >98% of all area burned. The effects of these large fire events can easily be discriminated on a variety of satellite remote sensing system. Studies are currently underway to compare field data of surface characteristics in a fire-disturbed spruce forest in east-central Alaska to a variety of satellite data collected over this region. These studies have shown that remote sensing data collected in different regions of the electromagnetic spectrum can be used to estimate different surface characteristics related to the effects of the fire. The authors discuss how these satellite-derived surface parameters can be used to study patterns of carbon storage and release in fire-disturbed spruce forests. Three different aspects of the carbon cycle are presently being studied using multi-sensor satellite data: (1) the amount of carbon released during into the atmosphere via biomass burning during the fire event; (2) carbon flux rates after the fire due to aerobic (CO/sub 2/) and anaerobic (CH/sub 4/) decomposition; and (3) patterns of carbon storage in aboveground biomass during secondary succession. The authors illustrate how satellite-remote sensing data can be used to study these processes.<>
{"title":"Estimating carbon storage and release in a fire-disturbed boreal forest using multi-sensor satellite data","authors":"E. Kasischke, P. Camille, H. Shugart, L. Bourgeau-Chavez, N. French","doi":"10.1109/COMEAS.1995.472351","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472351","url":null,"abstract":"Fire is a major disturbance regime for boreal forest and is also a major factor in the exchange of carbon between biotic components and the atmosphere. The occurrence of fire in boreal forests is extensive, and individual fire events typically cover large areas, with fires between 1000 and >1000000 ha in size accounting for >98% of all area burned. The effects of these large fire events can easily be discriminated on a variety of satellite remote sensing system. Studies are currently underway to compare field data of surface characteristics in a fire-disturbed spruce forest in east-central Alaska to a variety of satellite data collected over this region. These studies have shown that remote sensing data collected in different regions of the electromagnetic spectrum can be used to estimate different surface characteristics related to the effects of the fire. The authors discuss how these satellite-derived surface parameters can be used to study patterns of carbon storage and release in fire-disturbed spruce forests. Three different aspects of the carbon cycle are presently being studied using multi-sensor satellite data: (1) the amount of carbon released during into the atmosphere via biomass burning during the fire event; (2) carbon flux rates after the fire due to aerobic (CO/sub 2/) and anaerobic (CH/sub 4/) decomposition; and (3) patterns of carbon storage in aboveground biomass during secondary succession. The authors illustrate how satellite-remote sensing data can be used to study these processes.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129153919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472328
D. Kasilingam
In the event of an oil spill at sea, the most critical information needed is an estimate the amount of the spill and how it is dispersing. The thickness of the oil slick provides information needed to assess both these needs. Polarimetric synthetic aperture radar has been used to estimate the thickness of oil slicks. However, since a model that describes the measurements of a fully-polarimetric radar was not available, it was difficult to optimize this measurement technique. The two-scale, resonant scattering model is utilized to derive the backscatter cross-section of ocean surfaces that are covered by thin oil slicks. The model defines the complex scattering coefficients of the co-pol and cross-pol backscattered signals. The scattering coefficients are found as a function of the thickness of the oil slicks and its dielectric constant. The scattering matrices are converted to the corresponding Stokes matrices. The Stokes matrix is used to synthesize the backscattered signal for a variety of different polarizations. The scattering cross-section is found as a function of the ellipticity angle and the ellipse orientation angle. This information is used to train an artificial neural network to find the optimum polarization as a function of the dielectric constant and slick thickness. This artificial neural network is used to extract the slick thickness. Estimates of the resolution of the thickness measurement are also given. The effect of phase noise and speckle on the accuracy of the thickness measurement are also estimated. It is concluded that a fully polarimetric, millimeter wave radar, such as a 33 GHz SAR, is adequate for estimating the thickness of most moderately thick oil spills.<>
{"title":"Polarimetric radar signatures of oil slicks for measuring slick thickness","authors":"D. Kasilingam","doi":"10.1109/COMEAS.1995.472328","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472328","url":null,"abstract":"In the event of an oil spill at sea, the most critical information needed is an estimate the amount of the spill and how it is dispersing. The thickness of the oil slick provides information needed to assess both these needs. Polarimetric synthetic aperture radar has been used to estimate the thickness of oil slicks. However, since a model that describes the measurements of a fully-polarimetric radar was not available, it was difficult to optimize this measurement technique. The two-scale, resonant scattering model is utilized to derive the backscatter cross-section of ocean surfaces that are covered by thin oil slicks. The model defines the complex scattering coefficients of the co-pol and cross-pol backscattered signals. The scattering coefficients are found as a function of the thickness of the oil slicks and its dielectric constant. The scattering matrices are converted to the corresponding Stokes matrices. The Stokes matrix is used to synthesize the backscattered signal for a variety of different polarizations. The scattering cross-section is found as a function of the ellipticity angle and the ellipse orientation angle. This information is used to train an artificial neural network to find the optimum polarization as a function of the dielectric constant and slick thickness. This artificial neural network is used to extract the slick thickness. Estimates of the resolution of the thickness measurement are also given. The effect of phase noise and speckle on the accuracy of the thickness measurement are also estimated. It is concluded that a fully polarimetric, millimeter wave radar, such as a 33 GHz SAR, is adequate for estimating the thickness of most moderately thick oil spills.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131205308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472356
K. Araki, H. Nakamura, R. Sato, M. Shinriki, H. Sakamoto
The outline of terrain profile section is so complex that the construction of a mathematical model by some classical models such as AR or ARMA may seem hopeless. The authors study how to model a terrain profile section and the corresponding identification, that is represented by fractional Brownian motion with different fractal dimension. This model is improved by additional information resulted from reflection coefficient on the surface of ground, vegetation cover or water.<>
{"title":"Identification method on mathematical model of terrain profile section and experimental results by the millimeter wave altimeter","authors":"K. Araki, H. Nakamura, R. Sato, M. Shinriki, H. Sakamoto","doi":"10.1109/COMEAS.1995.472356","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472356","url":null,"abstract":"The outline of terrain profile section is so complex that the construction of a mathematical model by some classical models such as AR or ARMA may seem hopeless. The authors study how to model a terrain profile section and the corresponding identification, that is represented by fractional Brownian motion with different fractal dimension. This model is improved by additional information resulted from reflection coefficient on the surface of ground, vegetation cover or water.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"169 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113980512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472391
D. Kieu, A. Stogryn
The SSM/T-1 B3 and SSM/T-2 B4 units were successfully launched on August 29th, 1994. The SSM/T-2 instrument is a five channel, microwave total-power radiometer. It has three channels near the 183.31 GHz water vapor resonance line and two window channels (91 GHz and 150 GHz). The SSM/T-1 is a cross-track step scanning seven-channel Dicke microwave radiometer instrument. It operates in the oxygen absorption region at center frequencies of 50.5, 53.2, 54.35, 54.9, 58.4, 58.9, and 59.4 GHz. At a nominal orbit at an altitude of 833 km, brightness temperatures from the SSM/T-1 and SSM/T-2 instruments are used in the AFGWC's (Air Force Global Weather Center) weather prediction models. The SSM/T-2 ground processing software provides profiles of relative humidity, and absolute humidity, and water vapor mass at six mandatory pressure levels. The SSM/T-1 ground processing software estimates air temperature profiles at fifteen pressure levels and the tropopause. The SSM/T-1 f33 and SS.<>
{"title":"Early-orbit performance of the special Sensor Microwave Water-Vapor Profiler (SSM/T-2 B4) and Special Sensor Microwave Air-Temperature Sounder (SSM/T-1 B3)","authors":"D. Kieu, A. Stogryn","doi":"10.1109/COMEAS.1995.472391","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472391","url":null,"abstract":"The SSM/T-1 B3 and SSM/T-2 B4 units were successfully launched on August 29th, 1994. The SSM/T-2 instrument is a five channel, microwave total-power radiometer. It has three channels near the 183.31 GHz water vapor resonance line and two window channels (91 GHz and 150 GHz). The SSM/T-1 is a cross-track step scanning seven-channel Dicke microwave radiometer instrument. It operates in the oxygen absorption region at center frequencies of 50.5, 53.2, 54.35, 54.9, 58.4, 58.9, and 59.4 GHz. At a nominal orbit at an altitude of 833 km, brightness temperatures from the SSM/T-1 and SSM/T-2 instruments are used in the AFGWC's (Air Force Global Weather Center) weather prediction models. The SSM/T-2 ground processing software provides profiles of relative humidity, and absolute humidity, and water vapor mass at six mandatory pressure levels. The SSM/T-1 ground processing software estimates air temperature profiles at fifteen pressure levels and the tropopause. The SSM/T-1 f33 and SS.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131842865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472363
E. Eloranta, P. Piironen
The High Spectral Resolution Lidar (HSRL) provides robust profiles of the scattering cross section in clouds. In addition, a receiver channel with a computer controlled angular field of view provides measurements of multiple scattering. Using the measured scattering cross section profile and a computer model describing the dependence of the multiply scattered lidar return on the width of the diffraction peak, the multiply scattered signal can provide particle size information. Unfortunately, the multiply scattered lidar return is also a function of the weighted average of the scattering phase function near 180/spl deg/. The weighting function is the probability distribution of scattering angles for the near backscatter event that sends the, multiply scattered photon back towards the receiver. Since the particle size distribution is unknown, it is not easy to estimate this value. This is especially true when the cloud is comprised of ice crystals and both particle size and shape are unknown. To avoid this problem, the authors have implemented an additional data channel. Photons which fall outside of the field stop are directed through an I/sub 2/ absorption filter and then to PMT 4. Only photons which have been deflected out of the field of view by multiple scattering are detected, The I/sub 2/ filter transmits only the spectral wings of the Doppler broadened molecular backscattering. Photons backscattered from cloud particles are removed. Thus, this channel detects photons which have encountered one or more forward scatterings by cloud particles coupled with a single backscatter described by the Rayleigh phase function.<>
{"title":"Modification of the High Spectral Resolution Lidar for the measurement of multiply scattered lidar returns","authors":"E. Eloranta, P. Piironen","doi":"10.1109/COMEAS.1995.472363","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472363","url":null,"abstract":"The High Spectral Resolution Lidar (HSRL) provides robust profiles of the scattering cross section in clouds. In addition, a receiver channel with a computer controlled angular field of view provides measurements of multiple scattering. Using the measured scattering cross section profile and a computer model describing the dependence of the multiply scattered lidar return on the width of the diffraction peak, the multiply scattered signal can provide particle size information. Unfortunately, the multiply scattered lidar return is also a function of the weighted average of the scattering phase function near 180/spl deg/. The weighting function is the probability distribution of scattering angles for the near backscatter event that sends the, multiply scattered photon back towards the receiver. Since the particle size distribution is unknown, it is not easy to estimate this value. This is especially true when the cloud is comprised of ice crystals and both particle size and shape are unknown. To avoid this problem, the authors have implemented an additional data channel. Photons which fall outside of the field stop are directed through an I/sub 2/ absorption filter and then to PMT 4. Only photons which have been deflected out of the field of view by multiple scattering are detected, The I/sub 2/ filter transmits only the spectral wings of the Doppler broadened molecular backscattering. Photons backscattered from cloud particles are removed. Thus, this channel detects photons which have encountered one or more forward scatterings by cloud particles coupled with a single backscatter described by the Rayleigh phase function.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131488244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1995-04-03DOI: 10.1109/COMEAS.1995.472365
W. Boerner
"WISIP: Wideband (/spl mu/Hz-PHz) Interferometric Sensing and Imaging Polarimetry" has become an indispensable tool in wide area environmental surveillance of the terrestrial and planetary covers. It allows dynamic optimal image feature extraction of significant characteristics of desirable target and/or target sections with simultaneous suppression of undesirable background clutter/speckle at hitherto unknown clarity and of never achieved quality. "WISIP" may be adopted to the detection, recognition, and identification (DRI) of any stationary, moving, or vibrating target versus arbitrary stationary, dynamically changing or moving geophysical environments. A comprehensive overview is presented on how these modern high resolution/precision complete polarimetric coregistered signature sensing and interferometric POL-SAR imaging techniques, complemented by 111 integration of novel navigational electronic tools, such as DGPS, will advance electromagnetic vector wave sensing and imaging towards limits of physical realizability. Various examples utilizing NASA-JPL/AIR-SAR, NAWC/P3-POL-SAR, DLR-OPH/DO-POL-SAR airborne, ERS-1, JERS-1 satellite and SIR-C/X-SAR shuttle imaging data sets dealing with the recent Mississippi-Missouri/USA 1993 and Werra/FRG floods and various earthquake surface deformation events will be presented for demonstrating the utility of WISIP.<>
{"title":"Polarimetry in Wideband Interferometric Sensing and Imaging","authors":"W. Boerner","doi":"10.1109/COMEAS.1995.472365","DOIUrl":"https://doi.org/10.1109/COMEAS.1995.472365","url":null,"abstract":"\"WISIP: Wideband (/spl mu/Hz-PHz) Interferometric Sensing and Imaging Polarimetry\" has become an indispensable tool in wide area environmental surveillance of the terrestrial and planetary covers. It allows dynamic optimal image feature extraction of significant characteristics of desirable target and/or target sections with simultaneous suppression of undesirable background clutter/speckle at hitherto unknown clarity and of never achieved quality. \"WISIP\" may be adopted to the detection, recognition, and identification (DRI) of any stationary, moving, or vibrating target versus arbitrary stationary, dynamically changing or moving geophysical environments. A comprehensive overview is presented on how these modern high resolution/precision complete polarimetric coregistered signature sensing and interferometric POL-SAR imaging techniques, complemented by 111 integration of novel navigational electronic tools, such as DGPS, will advance electromagnetic vector wave sensing and imaging towards limits of physical realizability. Various examples utilizing NASA-JPL/AIR-SAR, NAWC/P3-POL-SAR, DLR-OPH/DO-POL-SAR airborne, ERS-1, JERS-1 satellite and SIR-C/X-SAR shuttle imaging data sets dealing with the recent Mississippi-Missouri/USA 1993 and Werra/FRG floods and various earthquake surface deformation events will be presented for demonstrating the utility of WISIP.<<ETX>>","PeriodicalId":274878,"journal":{"name":"Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129005376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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