Chlorophyll-a Estimation in Turbid Waters Using Combined SAR Data With Hyperspectral Reflectance Data: A Case Study in Lake Taihu, China - Yuanzhi Zhang; Martti Hallikainen; Hongsheng Zhang; Hongtao Duan; Yu Li; X. San Liang (IEEE J. Sel. Top. Appl. Earth Obs. Remote. Sens., 2018)

Multi-Sensor Sar Data for Improved Modeling of Microwave Brightness Temperature over Boreal Forest - Oleg Antropov; Jaakko Seppänen; Martti Hallikainen; Jaan Praks; Thomas Jagdhuber (2018 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2018, Valencia, Spain, July 22-27, 2018, 2018)

Comparison of Experimental Brightness Temperatures for Snow on Lake Ice with Those for Snow on Terrain - Martti Hallikainen; Matti Vaaja; Jaakko Seppänen; Jaan Praks (2018 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2018, Valencia, Spain, July 22-27, 2018, 2018)

Measurements and Simulation of a Concentric Raised Bog With a 1.4-GHz Radiometer - Jaakko Seppänen; Jaan Praks; Pauli Sievinen; Anssi Hakkarainen; Martti Hallikainen (IEEE Geosci. Remote. Sens. Lett., 2017)

Improved Characterization of Forest Transmissivity Within the L-MEB Model Using Multisensor SAR Data - Jaakko Seppänen; Oleg Antropov; Thomas Jagdhuber; Martti Hallikainen; Janne Heiskanen; Jaan Praks (IEEE Geosci. Remote. Sens. Lett., 2017)

Foreword to the Special Issue on the 14th Specialist Meeting on Microwave Radiometry and Remote Sensing of the Environment (MicroRad 2016) - Martti T. Hallikainen; Jaan Praks; Jiancheng Shi; Andreas Colliander (IEEE J. Sel. Top. Appl. Earth Obs. Remote. Sens., 2017)

Retardation Plate for the Calibration of a Fully Polarimetric Radiometer: Determination of Characteristics - Janne Lahtinen; Martti T. Hallikainen (IEEE J. Sel. Top. Appl. Earth Obs. Remote. Sens., 2017)

Soil Moisture Retrievals Over Partially Forested Areas in Aurajoki Catchment, Western Finland - Jaakko Seppänen; Juho Jakkila; Jaan Praks; Martti T. Hallikainen (IEEE J. Sel. Top. Appl. Earth Obs. Remote. Sens., 2017)

Microwave brightness temperature of snow on terrain and lake ice revisited: Data and simulations - Martti T. Hallikainen (2017 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2017, Fort Worth, TX, USA, July 23-28, 2017, 2017)

Measurements of Boreal Coniferous Forest Soil and Humus With an Airborne Radiometer - Jaakko Seppänen; Juha Kainulainen; Janne Heiskanen; Jaan Praks; Martti Hallikainen (IEEE J. Sel. Top. Appl. Earth Obs. Remote. Sens., 2016)

Microwave brightness temperature of snow: Observations and simulations - Martti Hallikainen; Juha Lemmetyinen (2016 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2016, Beijing, China, July 10-15, 2016, 2016)

Modeling Radar Attenuation by a Low Melting Layer With Optimized Model Parameters at C-Band - Annakaisa von Lerber; Dmitri Moisseev; Jussi Leinonen; Jarmo Koistinen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2015)

The Effect of Boreal Forest Canopy in Satellite Snow Mapping - A Multisensor Analysis - Juval Cohen; Juha Lemmetyinen; Jouni Pulliainen; Kirsikka Heinilä; Francesco Montomoli; Jaakko Seppänen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2015)

AALTO-1 earth observation cubesat mission - Educational outcomes - Jaan Praks; Antti Kestila; Tuomas Tikka; Hannu Leppinen; O. Khurshid; Martti Hallikainen (2015 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2015, Milan, Italy, July 26-31, 2015, 2015)

Multifrequency microwave radiometry of snow on lake ice: Observations and simulations - Martti Hallikainen; Juha Lemmetyinen; Matti Vaaja; Jaakko Seppänen; Jaan Praks (2015 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2015, Milan, Italy, July 26-31, 2015, 2015)

Observation and Modeling of the Microwave Brightness Temperature of Snow-Covered Frozen Lakes and Wetlands - Anna Kontu; Juha Lemmetyinen; Jouni Pulliainen; Jaakko Seppänen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2014)

Land Cover and Soil Type Mapping From Spaceborne PolSAR Data at L-Band With Probabilistic Neural Network - Oleg Antropov; Yrjö Rauste; Heikki Astola; Jaan Praks; Tuomas Häme; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2014)

Brightness temperature behavior of snow on lake ice over a wide frequency range - Martti Hallikainen; Matti Vaaja; Jaakko Seppänen; Anssi Hakkarainen; Juha Kainulainen (2014 IEEE Geoscience and Remote Sensing Symposium, IGARSS 2014, Quebec City, QC, Canada, July 13-18, 2014, 2014)

Validation of SMOS soil moisture retrievals in Aurajoki catchment, Western Finland - Jaakko Seppänen; Martti Hallikainen; Juho Jakkila (2014 IEEE Geoscience and Remote Sensing Symposium, IGARSS 2014, Quebec City, QC, Canada, July 13-18, 2014, 2014)

Microwave Dielectric Properties of Materials - Martti Hallikainen (Encyclopedia of Remote Sensing, 2014)

Morphological Database of Paris for Atmospheric Modeling Purposes - Andreas Tack; Jarkko Koskinen; Antti Hellsten; Pauli Sievinen; Igor Esau; Jaan Praks; Jaakko Kukkonen; Martti Hallikainen (IEEE J. Sel. Top. Appl. Earth Obs. Remote. Sens., 2012)

Radiometric Performance of the SMOS Reference Radiometers - Assessment After One Year of Operation - Juha Kainulainen; Andreas Colliander; Josep Closa; Manuel Martín-Neira; Roger Oliva; Guillermo Buenadicha; Pilar Rubiales Alcaine; Anssi Hakkarainen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2012)

LIDAR-Aided SAR Interferometry Studies in Boreal Forest: Scattering Phase Center and Extinction Coefficient at X- and L-Band - Jaan Praks; Oleg Antropov; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2012)

Multifrequency microwave radiometer measurements of snow on lake ice - Martti Hallikainen; Matti Vaaja; Annakaisa von Lerber; Juha Kainulainen; Jaakko Seppänen; Juha Lemmetyinen (2012 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2012, Munich, Germany, July 22-27, 2012, 2012)

Moisture retrievals of boreal forest soil using HUT-2D synthetic aperture radiometer - Jaakko Seppänen; Juha Kainulainen; Martti Hallikainen (2012 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2012, Munich, Germany, July 22-27, 2012, 2012)

Boreal forest tree height estimation from interferometric TanDEM-X images - Jaan Praks; Martti Hallikainen; Oleg Antropov; Daniel Molina (2012 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2012, Munich, Germany, July 22-27, 2012, 2012)

Thin sea ice identification in the Kara Sea using AMSR-E data - Annakaisa von Lerber; Marko Mäkynen; Markku Similä; Pauli Sievinen; Martti T. Hallikainen (2012 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2012, Munich, Germany, July 22-27, 2012, 2012)

Peatland delineation under forest canopy with polsar data using model based decomposition technique - Oleg Antropov; Yrjö Rauste; Jaan Praks; Martti Hallikainen; Tuomas Häme (2012 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2012, Munich, Germany, July 22-27, 2012, 2012)

GRS-S Awards Presented at IGARSS 2009 - Martti Hallikainen; Werner Wiesbeck; R. Keith Raney; Kiyo Tomiyasu; Paolo Pampaloni; Roger H. Lang; Klaus Seidel; Charles Elachi; Akiro Ishimaru; Wolfgang Keydel; John Reagan (IEEE Trans. Geosci. Remote. Sens., 2011)

Experimental Study on Radiometric Performance of Synthetic Aperture Radiometer HUT-2D - Measurements of Natural Targets - Juha Kainulainen; Kimmo Rautiainen; Juha Lemmetyinen; Jaakko Seppänen; Pauli Sievinen; Matias Takala; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2011)

Detection of a Sea Surface Salinity Gradient Using Data Sets of Airborne Synthetic Aperture Radiometer HUT-2-D and a GNSS-R Instrument - Juha Kainulainen; Kimmo Rautiainen; Juha Lemmetyinen; Martti T. Hallikainen; Fernando Martín-Porqueras; Manuel Martín-Neira (IEEE Trans. Geosci. Remote. Sens., 2011)

Modeling melting layer radar observations at GPM frequencies; comparison to measurements - Annakaisa von Lerber; Dmitri Moisseev; Jussi Leinonen; Jani Tyynela; V. Chandrasekar; Martti T. Hallikainen (2011 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2011, Vancouver, BC, Canada, July 24-29, 2011, 2011)

Synthetic aperture radiometer measurements of freezing soil - Jaakko Seppänen; Juha Kainulainen; Martti Hallikainen; Juha Lemmetyinen; Kimmo Rautiainen (2011 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2011, Vancouver, BC, Canada, July 24-29, 2011, 2011)

Lessons learned from HUT-2D L-band airborne demonstrator - Juha Kainulainen; Kimmo Rautiainen; Martti T. Hallikainen (2011 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2011, Vancouver, BC, Canada, July 24-29, 2011, 2011)

Microwave emission signature of snow-covered lake ice - Martti T. Hallikainen; Pauli Sievinen; Jaakko Seppänen; Matti Vaaja; Annakaisa von Lerber; Erkka Rouhe; Juha Lemmetyinen (2011 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2011, Vancouver, BC, Canada, July 24-29, 2011, 2011)

Aalto-1 - An experimental nanosatellite for hyperspectral remote sensing - Jaan Praks; Antti Kestila; Martti Hallikainen; Heikki Saari; Jarkko Antila; Pekka Janhunen; Rami Vainio (2011 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2011, Vancouver, BC, Canada, July 24-29, 2011, 2011)

SMOS calibration and validation activities with airborne interferometric radiometer HUT-2D during spring 2010 - Juha Kainulainen; Kimmo Rautiainen; Pauli Sievinen; Jaakko Seppänen; Erkka Rouhe; Martti Hallikainen; Johanna T. Dall'Amico; Florian Schlenz; Alexander Loew; Alexander Bircher; Carsten Montzka (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2010, July 25-30, 2010, Honolulu, Hawaii, USA, Proceedings, 2010)

Polarimetric sar image visualization and interpretation with covariance matrix invariants - Jaan Praks; Martti Hallikainen; Elise Colin Koeniguer (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2010, July 25-30, 2010, Honolulu, Hawaii, USA, Proceedings, 2010)

Modeling attenuation of melting hydrometeors with a method based on volume integral equations - Annakaisa von Lerber; Timo Piepponen; Jarkko Koskinen; Dmitri Moisseev; Dmitri Kestilä; Jani Tyynela; Timo Nousiainen; Jarmo Koistinen; Ari Sihvola; Pasi Ylä-Oijala; Jaan Praks; Martti Hallikainen; et al. (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2010, July 25-30, 2010, Honolulu, Hawaii, USA, Proceedings, 2010)

Studies of radio frequency interference at L-band using an airborne 2-D interferometric radiometer - Martti Hallikainen; Juha Kainulainen; Jaakko Seppänen; Anssi Hakkarainen; Kimmo Rautiainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2010, July 25-30, 2010, Honolulu, Hawaii, USA, Proceedings, 2010)

Using Multilook Averaging for Coherently Modeled Scattering From a Pine Tree at L-Band - Jaan Praks; Jukka Sarvas; Martti Hallikainen; Jouni Pulliainen (IEEE Geosci. Remote. Sens. Lett., 2009)

Comparison of SAR-Based Snow-Covered Area Estimation Methods for the Boreal Forest Zone - Kari Luojus; Jouni Pulliainen; Alberto Blasco Cutrona; Sari Metsämäki; Martti T. Hallikainen (IEEE Geosci. Remote. Sens. Lett., 2009)

Simulation of ASIRAS Altimeter Echoes for Snow-Covered First-Year Sea Ice - Marko Mäkynen; Martti T. Hallikainen (IEEE Geosci. Remote. Sens. Lett., 2009)

Enhanced SAR-Based Snow-Covered Area Estimation Method for Boreal Forest Zone - Kari Luojus; Jouni Pulliainen; Sari Metsämäki; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2009)

A Comparison of Airborne Microwave Brightness Temperatures and Snowpack Properties Across the Boreal Forests of Finland and Western Canada - Juha Lemmetyinen; Chris Derksen; Jouni Pulliainen; J. Walter Strapp; Peter Toose; Anne E. Walker; Simo Tauriainen; Jörgen Pihlflyckt; Juha-Petri Kärnä; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2009)

Alternatives to Target Entropy and Alpha Angle in SAR Polarimetry - Jaan Praks; Elise Colin Koeniguer; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2009)

GRS-S Awards Presented at IGARSS 2008 - Martti Hallikainen; Werner Wiesbeck; R. Keith Raney; Kiyo Tomiyasu; Yoshio Yamaguchi; Roger H. Lang; Klaus Seidel (IEEE Trans. Geosci. Remote. Sens., 2009)

Sea Ice SAR Classification based on Edge Features - Juha Karvonen; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2009, July 12-17, 2009, University of Cape Town, Cape Town, South Africa, Proceedings, 2009)

Experimental and Modeling Studies of Microwave Remote Sensing of Seasonal Snow - Martti Hallikainen; Juha Lemmetyinen; Pauli Sievinen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2009, July 12-17, 2009, University of Cape Town, Cape Town, South Africa, Proceedings, 2009)

Soil Moisture Retrieval from HUT-2D Synthetic Aperture Radiometer Data - Jaakko Seppänen; Juha Kainulainen; Juha Lemmetyinen; Kimmo Rautiainen; Martti Hallikainen; Marko Mäkynen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2009, July 12-17, 2009, University of Cape Town, Cape Town, South Africa, Proceedings, 2009)

Boreal Forest Height Estimation with SAR Interferometry and Laser Measurements - Jaan Praks; Martti Hallikainen; Juha Hyyppä; Jaakko Seppänen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2009, July 12-17, 2009, University of Cape Town, Cape Town, South Africa, Proceedings, 2009)

The Atmosphere Influence to AMSR-E Measurements over Snow-covered Areas: Simulation and Experiments - Yubao Qiu; Jiancheng Shi; Juha Lemmetyinen; Anna Kontu; Jouni Pulliainen; Huadong Guo; James R. Wang; Lingmei Jiang; Martti Hallikainen; Li Zhang (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2009, July 12-17, 2009, University of Cape Town, Cape Town, South Africa, Proceedings, 2009)

Sea Surface Salinity Retrieval Demonstration using Datasets of Synthetic Aperture Radiometer HUT-2D - Juha Kainulainen; Kimmo Rautiainen; Juha Lemmetyinen; Martti Hallikainen; Fernando Martín-Porqueras; Manuel Martín-Neira (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2009, July 12-17, 2009, University of Cape Town, Cape Town, South Africa, Proceedings, 2009)

Experimental Validation Activities of HUT Snow Emission Model - Juha Lemmetyinen; Anna Kontu; Yubao Qiu; Jouni Pulliainen; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2009, July 12-17, 2009, University of Cape Town, Cape Town, South Africa, Proceedings, 2009)

Urban Morphology Retrieval Bymeansofremote Sensing for the Modelling of Atmospheric Dispersion and Micro-meteorology - Pauli Sievinen; Jaan Praks; Jarkko Koskinen; Martti Hallikainen; Jaakko Kukkonen; Antti Hellsten (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2009, July 12-17, 2009, University of Cape Town, Cape Town, South Africa, Proceedings, 2009)

Helsinki University of Technology L-Band Airborne Synthetic Aperture Radiometer - Kimmo Rautiainen; Juha Kainulainen; Tuomo Auer; Jörgen Pihlflyckt; Jani Kettunen; Martti Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2008)

Baltic Sea Ice Thickness Charts based on Thermodynamic Snow/Ice Model, C-band SAR Classification and Ice Motion Detection - Juha Karvonen; Bin Cheng; Markku Similä; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2008, July 8-11, 2008, Boston, Massachusetts, USA, Proceedings, 2008)

Development of SAR-Based Snow-Covered Area Estimation Method for Borel Forest Zone - Kari Luojus; Jouni Pulliainen; Sari Metsämäki; Guifre Molera; Risto Nakari; Juha-Petri Kärnä; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2008, July 8-11, 2008, Boston, Massachusetts, USA, Proceedings, 2008)

Results from Microwave Radiometer Campaign of Seasonal Snow and Comparison with Emission Models - Martti Hallikainen; Panu Lahtinen; Timo Piepponen; Lauri Honkavaara; Aleksis Schäfer (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2008, July 8-11, 2008, Boston, Massachusetts, USA, Proceedings, 2008)

SAR Coherence Tomography for Boreal Forest with Aid of Laser Measurements - Jaan Praks; Florian Kugler; Juha Hyyppä; Konstantinos Papathanassiou; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2008, July 8-11, 2008, Boston, Massachusetts, USA, Proceedings, 2008)

Simulation of ASIRAS Multilooked Echoes for Snow Covered Sea Ice - Marko Mäkynen; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2008, July 8-11, 2008, Boston, Massachusetts, USA, Proceedings, 2008)

The AMSR-E Instantaneous Emissivity Estimation and its Correlation, Frequency Dependency Analysis over Different Land Covers - Yubao Qiu; Jiancheng Shi; Martti Hallikainen; Juha Lemmetyinen; Jouni Pulliainen; Jarkko Koskinen; Anna Kontu (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2008, July 8-11, 2008, Boston, Massachusetts, USA, Proceedings, 2008)

Determination of Snow Emission on Lake Ice from Airborne Passive Microwave Measurements - Anna Kontu; Sami Kemppainen; Juha Lemmetyinen; Jouni Pulliainen; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2008, July 8-11, 2008, Boston, Massachusetts, USA, Proceedings, 2008)

Comparison Between Envisat SAR and 3-D Laser Scanner Statistics for the Baltic Sea Ice - Markku Similä; Marko Mäkynen; Istvan Heiler; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2008, July 8-11, 2008, Boston, Massachusetts, USA, Proceedings, 2008)

First 2-D Interferometric Radiometer Imaging of the Earth From an Aircraft - Juha Kainulainen; Kimmo Rautiainen; Simo Tauriainen; Tuomo Auer; Jani Kettunen; Martti Hallikainen (IEEE Geosci. Remote. Sens. Lett., 2007)

Height Estimation of Boreal Forest: Interferometric Model-Based Inversion at L- and X-Band Versus HUTSCAT Profiling Scatterometer - Jaan Praks; Florian Kugler; Konstantinos P. Papathanassiou; Irena Hajnsek; Martti Hallikainen (IEEE Geosci. Remote. Sens. Lett., 2007)

Snow-Covered Area Estimation Using Satellite Radar Wide-Swath Images - Kari Luojus; Jouni Pulliainen; Sari Metsämäki; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2007)

Comparisons Between SAR Backscattering Coefficient and Results of a Thermodynamic Snow/Ice Model for the Baltic Sea Land-Fast Sea Ice - Marko Mäkynen; Bin Cheng; Markku Similä; Timo Vihma; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2007)

Development and Calibration of SMOS Reference Radiometer - Andreas Colliander; Lasse Ruokokoski; Jani Suomela; Katriina Veijola; Jani Kettunen; Ville Kangas; Aleksi Aalto; Mikael Levander; Heli Greus; Martti T. Hallikainen; Janne Lahtinen (IEEE Trans. Geosci. Remote. Sens., 2007)

Sensitivity of Airborne 36.5-GHz Polarimetric Radiometer's Wind-Speed Measurement to Incidence Angle - Andreas Colliander; Janne Lahtinen; Simo Tauriainen; Jörgen Pihlflyckt; Juha Lemmetyinen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2007)

SMOS Calibration Subsystem - Juha Lemmetyinen; Josu Uusitalo; Juha Kainulainen; Kimmo Rautiainen; Nestori Fabritius; Mikael Levander; Ville Kangas; Heli Greus; Jörgen Pihlflyckt; Anna Kontu; Sami Kemppainen; Andreas Colliander; et al. (IEEE Trans. Geosci. Remote. Sens., 2007)

Radiometric performance of interferometric synthetic aperture radiometer HUT-2D - Juha Kainulainen; Kimmo Rautiainen; Martti Hallikainen; Matias Takala (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2007, July 23-28, 2007, Barcelona, Spain, Proceedings, 2007)

X-band extinction in boreal forest: Estimation by using E-SAR POLInSAR and HUTSCAT - Jaan Praks; Martti Hallikainen; Florian Kugler; Konstantinos P. Papathanassiou (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2007, July 23-28, 2007, Barcelona, Spain, Proceedings, 2007)

Use of quikscat ku-band scatterometer data for retrieval of seasonal snow characteristics in Finland - Martti Hallikainen; Pauli Sievinen; Yuanzhi Zhang; Pekka Halme (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2007, July 23-28, 2007, Barcelona, Spain, Proceedings, 2007)

Operational snow map production for whole eurasia using microwave radiometer and ground-based observations - Juha-Petri Kärnä; Juha Lemmetyinen; Martti Hallikainen; Panu Lahtinen; Jouni Pulliainen; Matias Takala (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2007, July 23-28, 2007, Barcelona, Spain, Proceedings, 2007)

Ground calibration of SMOS: NIR and CAS - Andreas Colliander; Juha Lemmetyinen; Josu Uusitalo; Jani Suomela; Katriina Veijola; Anna Kontu; Sami Kemppainen; Jörgen Pihlflyckt; Kimmo Rautiainen; Martti Hallikainen; Janne Lahtinen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2007, July 23-28, 2007, Barcelona, Spain, Proceedings, 2007)

Helsinki University of Technology Synthetic Aperture Radiometer -HUT-2D - Kimmo Rautiainen; Juha Kainulainen; Tuomo Auer; Simo Tauriainen; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2007, July 23-28, 2007, Barcelona, Spain, Proceedings, 2007)

Interpretation of C-band SAR backscattering coefficient time series for the Baltic Sea landfast sea ice using a 1-D thermodynamic snow/ice model - Marko Mäkynen; Bin Cheng; Markku Similä; Timo Vihma; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2007, July 23-28, 2007, Barcelona, Spain, Proceedings, 2007)

Assimilating spaceborne radar and ground-based weather station data for operational snow-covered area estimation - Kari Luojus; Jouni Pulliainen; Sari Metsämäki; Saku Anttila; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2007, July 23-28, 2007, Barcelona, Spain, Proceedings, 2007)

Thermal stabilized front-end PCB with active cold calibration load for L-band radiometer - Sami Kemppainen; Juha Lemmetyinen; Tuomo Auer; Andreas Colliander; Aleksi Aalto; Kimmo Rautiainen; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2007, July 23-28, 2007, Barcelona, Spain, Proceedings, 2007)

Accuracy assessment of SAR data-based snow-covered area estimation method - Kari Luojus; Jouni Pulliainen; Sari Metsämäki; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2006)

Calibration of End-to-End Phase Imbalance of Polarimetric Radiometers - Andreas Colliander; Jani Kettunen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2006)

Dependence between standard deviation and measurement length for C-band backscattering signatures of the Baltic Sea ice - Marko Mäkynen; Markku Similä; A. Terhikki Manninen; Martti T. Hallikainen; Juha A. Karvonen (IEEE Trans. Geosci. Remote. Sens., 2006)

A Comparison of Airborne Passive Microwave Brightness Temperatures and Snowpack Properties across the Boreal Forests of Finland and Western Canada - Chris Derksen; J. Walter Strapp; Anne E. Walker; Juha Lemmetyinen; Martti Hallikainen; Jouni Pulliainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2006, July 31 - August 4, 2006, Denver, Colorado, USA, Proceedings, 2006)

C-Band SAR Based Estimation of Baltic Sea Ice Thickness Distributions - Markku Similä; Juha Karvonen; Christian Haas; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2006, July 31 - August 4, 2006, Denver, Colorado, USA, Proceedings, 2006)

Mapping of Snow Water Equivalent and Snow Coverage from Combined EO and in situ Data for Climatic Studies and Hydrological Forecasting Models - Jouni Pulliainen; Juha-Petri Kärnä; Martti Hallikainen; Kari Luojus; Sari Metsämäki; Markus Huttunen; Saku Anttila (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2006, July 31 - August 4, 2006, Denver, Colorado, USA, Proceedings, 2006)

Development of Techniques to Retrieve Snow Covered Area (SCA) in Boreal Forests from Space-borne Microwave Observations - Kari Luojus; Juha-Petri Kärnä; Martti Hallikainen; Jouni Pulliainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2006, July 31 - August 4, 2006, Denver, Colorado, USA, Proceedings, 2006)

Results from a Ground-Based Microwave Multi-Frequency Radiometer Campaign of Seasonal Snow in Finland - Martti Hallikainen; Panu Lahtinen; Timo Piepponen; Lauri Honkavaara; Aleksis Schäfer (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2006, July 31 - August 4, 2006, Denver, Colorado, USA, Proceedings, 2006)

L-band Polarimetric Interferometry in Boreal Forest Parameter Estimation, a Case Study - Jaan Praks; Martti Hallikainen; Florian Kugler; Kostas Papathanassiou; Irena Hajnsek (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2006, July 31 - August 4, 2006, Denver, Colorado, USA, Proceedings, 2006)

SMOS Calibration Subsystem - Juha Lemmetyinen; Josu Uusitalo; Kimmo Rautiainen; Juha Kainulainen; Nestori Fabritius; Mikael Levander; Ville Kangas; Heli Greus; Jörgen Pihlflyckt; Anna Kontu; Sami Kemppainen; Martti Hallikainen; et al. (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2006, July 31 - August 4, 2006, Denver, Colorado, USA, Proceedings, 2006)

Foreword to the Special Issue on the 8th Specialist Meeting on Microwave Radiometry and Remote Sensing Applications (MicroRad04) - Nazzareno Pierdicca; Frank Silvio Marzano; Martti T. Hallikainen; Paolo Pampaloni; Ed R. Westwater (IEEE Trans. Geosci. Remote. Sens., 2005)

MIRAS reference radiometer: a fully polarimetric noise injection radiometer - Andreas Colliander; Simo Tauriainen; Tuomo Auer; Juha Kainulainen; Josu Uusitalo; Martti Toikka; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2005)

Investigating of snow wetness parameter using a two-phase backscattering model - Ali Nadir Arslan; Martti T. Hallikainen; Jouni Pulliainen (IEEE Trans. Geosci. Remote. Sens., 2005)

Snow covered area estimation using satellite radar wide swath images - Kari Luojus; Jouni Pulliainen; Sari Metsämäki; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2005, July 25-29, 2005, Seoul, Korea, Proceedings, 2005)

Feasibility of satellite Ku-band scatterometer data for retrieval of seasonal snow characteristics in Finland - Martti Hallikainen; Panu Lahtinen; Yuanzhi Zhang; Matias Takala; Jouni Pulliainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2005, July 25-29, 2005, Seoul, Korea, Proceedings, 2005)

Estimation of snow water equivalent and snow depth in boreal forests by assimilating AMSR-E observations with in situ observations - Jouni Pulliainen; Martti Hallikainen; Saku Anttila; Sari Metsämäki (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2005, July 25-29, 2005, Seoul, Korea, Proceedings, 2005)

Automatic detection of water bodies from spaceborne SAR images - Pekka Ahtonen; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2005, July 25-29, 2005, Seoul, Korea, Proceedings, 2005)

On SAR-based statistical ice thickness estimation in the baltic sea - Markku Similä; Juha Karvonen; Martti Hallikainen; Christian Haas (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2005, July 25-29, 2005, Seoul, Korea, Proceedings, 2005)

Spectrometer-derived variability for snow covered forest reflectances in the melting period - Miia Eskelinen; Jouni Pulliainen; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2005, July 25-29, 2005, Seoul, Korea, Proceedings, 2005)

Temperature variation compensation in engineering model of MIRAS reference radiometer - Andreas Colliander; Jani Suomela; Lasse Ruokokoski; Ville Kangas; Aleksi Aalto; Janne Lahtinen; Martti Hallikainen (IEEE International Geoscience & Remote Sensing Symposium, IGARSS 2005, July 25-29, 2005, Seoul, Korea, Proceedings, 2005)

Boreal forest coherence-based measures of interferometric pair suitability for operational stem volume retrieval - Marcus E. Engdahl; Jouni Pulliainen; Martti T. Hallikainen (IEEE Geosci. Remote. Sens. Lett., 2004)

Water quality classification of lakes using 250-m MODIS data - Sampsa S. Koponen; Kari Y. Kallio; Jouni Pulliainen; Jenni Vepsäläinen; Timo Pyhälahti; Martti Hallikainen (IEEE Geosci. Remote. Sens. Lett., 2004)

Detection of oil pollution on sea ice with airborne and spaceborne spectrometer - Jaan Praks; Miia Eskelinen; Jouni Pulliainen; Timo Pyhälahti; Martti Hallikainen (2004 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2004, Anchorage, Alaska, USA, 20-24 September 2004, 2004)

Evaluation of in-orbit temperature variation on performance of MIRAS prototype noise injection radiometer - Andreas Colliander; Simo Tauriainen; Tuomo Auer; Josu Uusitalo; Martti Toikka; Martti Hallikainen (2004 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2004, Anchorage, Alaska, USA, 20-24 September 2004, 2004)

Monitoring of soil moisture and vegetation water content variations in boreal forest from C-band SAR data - Jouni Pulliainen; Pertti Hari; Martti Hallikainen; Niina Patrikainen; Martti Perämäki; Pasi Kolari (2004 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2004, Anchorage, Alaska, USA, 20-24 September 2004, 2004)

Investigation of the effect of variable viewing angle with airborne multiangular measurements - Miia Eskelinen; Jouni Pulliainen; Jaan Praks; Martti Hallikainen (2004 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2004, Anchorage, Alaska, USA, 20-24 September 2004, 2004)

Retrieval of snow characteristics from spaceborne scatterometer data - Martti Hallikainen; Pekka Halme; Panu Lahtinen; Jouni Pulliainen (2004 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2004, Anchorage, Alaska, USA, 20-24 September 2004, 2004)

Dependence between spatial statistics and distance for C-band backscattering signatures of the Baltic Sea ice - Marko Mäkynen; A. Terhikki Manninen; Markku Similä; Juha Karvonen; Martti Hallikainen (2004 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2004, Anchorage, Alaska, USA, 20-24 September 2004, 2004)

Accuracy assessment for HUT snow covered area estimation method - Kari Luojus; Jouni Pulliainen; Martti Hallikainen (2004 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2004, Anchorage, Alaska, USA, 20-24 September 2004, 2004)

Estimation of snow pack characteristics and snow covered area in boreal forests from ERS-2 SAR and Envisat ASAR data - Jouni Pulliainen; Kari Luojus; Martti Hallikainen; Sari Metsämäki; Jarkko Koskinen; Juha-Petri Kärnä; Markus Huttunen; Sirpa Rasmus (2004 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2004, Anchorage, Alaska, USA, 20-24 September 2004, 2004)

HUT fully polarimetric calibration standard for microwave radiometry - Janne Lahtinen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2003)

Water quality retrievals from combined Landsat TM data and ERS-2 SAR data in the Gulf of Finland - Yuanzhi Zhang; Jouni Pulliainen; Sampsa S. Koponen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2003)

Fully polarimetric microwave radiometer for remote sensing - Janne Lahtinen; Jörgen Pihlflyckt; Ilkka Mononen; Simo Tauriainen; Martti Kemppinen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2003)

Classification and retrieval of dry snow parameters by means of SMM/I data and artificial neural networks - Marco Tedesco; Paolo Pampaloni; Jouni Pulliainen; Martti Hallikainen (2003 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2003, Toulouse, France, July 21-15, 2003, 2003)

Combined active and passive microwave remote sensing of snow in Finland - Martti T. Hallikainen; Pekka Halme; Matias Takala; Jouni Pulliainen (2003 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2003, Toulouse, France, July 21-15, 2003, 2003)

Examination of forest polarimetric backscattering with coherent cylinder model - Jaan Praks; Jouni Pulliainen; Pekka Ahtonen; Martti Hallikainen (2003 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2003, Toulouse, France, July 21-15, 2003, 2003)

Development of airborne aperture synthetic radiometer (HUT-2D) - Kimmo Rautiainen; Robert Butora; Tuomo Auer; Jani Kettunen; Juha Kainulainen; Ilkka Mononen; Diego Beltrami; Martti Hallikainen (2003 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2003, Toulouse, France, July 21-15, 2003, 2003)

Investigating relationship between correlation lengths and physical properties of wet snow - Ali Nadir Arslan; Jouni Pulliainen; Martti Hallikainen (2003 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2003, Toulouse, France, July 21-15, 2003, 2003)

Combined land-cover classification and stem volume estimation using multitemporal ERS tandem INSAR data - Marcus E. Engdahl; Jouni Pulliainen; Martti Hallikainen (2003 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2003, Toulouse, France, July 21-15, 2003, 2003)

Development and characterization of fully polarimetric noise injection radiometer for MIRAS - Andreas Colliander; Simo Tauriainen; Tuomo Auer; Juha Kainulainen; Josu Uusitalo; Martti Toikka; Martti Hallikainen (2003 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2003, Toulouse, France, July 21-15, 2003, 2003)

The use of airborne optical spectrometer data in snow cover monitoring - Miia Eskelinen; Sari Metsämäki; Jouni Pulliainen; Martti Hallikainen; Jaan Praks (2003 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2003, Toulouse, France, July 21-15, 2003, 2003)

Estimation of the beginning of snow melt period using SSM/I data - Matias Takala; Jouni Pulliainen; Markus Huttunen; Martti Hallikainen (2003 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2003, Toulouse, France, July 21-15, 2003, 2003)

Incidence angle dependence of the statistical properties of C-band HH-polarization backscattering signatures of the Baltic Sea ice - Marko Mäkynen; A. Terhikki Manninen; Markku Similä; Juha A. Karvonen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2002)

Comparison of analog continuum correlators for remote sensing and radio astronomy - Olli Koistinen; Janne Lahtinen; Martti T. Hallikainen (IEEE Trans. Instrum. Meas., 2002)

Effects of temperature and moisture of snow and soil on SSM/I response to snow - Martti Hallikainen; Pekka Halme; Matias Takala; Jouni Pulliainen (IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2002, Toronto, Ontario, Canada, 24-28 June 2002, 2002)

Assimilation of space-borne microwave radiometer and discrete ground-based data in snow depth mapping: a case study for northern Eurasia - Jouni Pulliainen; Matias Takala; Martti Hallikainen (IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2002, Toronto, Ontario, Canada, 24-28 June 2002, 2002)

Incidence angle dependence of the mean C-band HH-polarization backscattering signatures of the Baltic Sea ice - Marko Mäkynen; A. Terhikki Manninen; Markku Similä; Juha Karvonen; Martti Hallikainen (IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2002, Toronto, Ontario, Canada, 24-28 June 2002, 2002)

Estimation of boreal forest biomass from multi-temporal INSAR data by inverting an empirical backscattering-coherence model - Jouni Pulliainen; Marcus E. Engdahl; Martti Hallikainen (IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2002, Toronto, Ontario, Canada, 24-28 June 2002, 2002)

Detection of sea surface temperature (SST) using AVHRR data in the Gulf of Finland - Yuanzhi Zhang; Jouni Pulliainen; Sampsa S. Koponen; Martti Hallikainen (IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2002, Toronto, Ontario, Canada, 24-28 June 2002, 2002)

Soil moisture retrieval by SMOS: a global feasibility study - Thierry Pellarin; Jean-Christophe Calvet; Jean-Pierre Wigneron; Lester P. Simmonds; Ernesto López-Baeza; Michael Berger; Adriano Camps; André Chanzy; Paolo Ferrazzoli; Martti T. Hallikainen; Yann H. Kerr; Christian Mätzler; et al. (IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2002, Toronto, Ontario, Canada, 24-28 June 2002, 2002)

Scattering from wet snow by applying strong fluctuation theory - Ali Nadir Arslan; Huining Wang; Jarkko Koskinen; Jouni Pulliainen; Martti Hallikainen (IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2002, Toronto, Ontario, Canada, 24-28 June 2002, 2002)

The seasonal behavior of interferometric coherence in boreal forest - Jarkko Koskinen; Jouni Pulliainen; Juha Hyyppä; Marcus E. Engdahl; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2001)

A Bayesian classification model for sea ice roughness from scatterometer data - Markku Similä; Elja Arjas; Marko Mäkynen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2001)

Measurements and modeling of vertical backscatter distribution in forest canopy - Jean-Michel Martinez; Nicolas Floury; Thuy Le Toan; André Beaudoin; Martti T. Hallikainen; Marko Mäkynen (IEEE Trans. Geosci. Remote. Sens., 2000)

Landuse mapping with ERS SAR interferometry - Tazio Strozzi; Patrik B. G. Dammert; Urs Wegmüller; Jean-Michel Martinez; Jan I. H. Askne; André Beaudoin; Martti Hallikainen (IEEE Trans. Geosci. Remote. Sens., 2000)

Retrieval of biomass in boreal forests from multitemporal ERS-1 and JERS-1 SAR images - Lauri Kurvonen; Jouni Pulliainen; Martti Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1999)

Development of a synergetic sea ice retrieval method for the ERS-1 AMI wind scatterometer and SSM/I radiometer - Jochen Grandell; Johnny A. Johannessen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1999)

Textural information of multitemporal ERS-1 and JERS-1 SAR images with applications to land and forest type classification in boreal zone - Lauri Kurvonen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1999)

Multitemporal behavior of L- and C-band SAR observations of boreal forests - Jouni Pulliainen; Lauri Kurvonen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1999)

HUT snow emission model and its applicability to snow water equivalent retrieval - Jouni Pulliainen; Jochen Grandell; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1999)

Calibration accuracy of the HUTSCAT airborne scatterometer - Juha Hyyppä; Marko Mäkynen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1999)

Seasonal comparison of HUTSCAT ranging scatterometer and ERS-1 SAR microwave signatures of boreal forest zone - Jarkko Koskinen; Jouni Pulliainen; Marko Mäkynen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1999)

Passive microwave measurements of snow-covered forest areas in EMAC'95 - Nerijus Kruopis; Jaan Praks; Ali Nadir Arslan; Hanna M. Alasalmi; Jarkko Koskinen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1999)

Application of ERS-1 wind scatterometer data to soil frost and soil moisture monitoring in boreal forest zone - Jouni Pulliainen; A. Terhikki Manninen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1998)

Influence of land-cover category on brightness temperature of snow - Lauri Kurvonen; Martti Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1997)

Radar-derived standwise forest inventory - Juha Hyyppä; Jouni Pulliainen; Martti Hallikainen; Asko Saatsi (IEEE Trans. Geosci. Remote. Sens., 1997)

The use of ERS-1 SAR data in snow melt monitoring - Jarkko Koskinen; Jouni Pulliainen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1997)

Retrieval of surface temperature in boreal forest zone from SSM/I data - Jouni Pulliainen; Jochen Grandell; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1997)

Seasonal dynamics of C-band backscatter of boreal forests with applications to biomass and soil moisture estimation - Jouni Pulliainen; P. J. Mikhela; Martti T. Hallikainen; Jari-Pekka Ikonen (IEEE Trans. Geosci. Remote. Sens., 1996)

Classification of Baltic Sea ice types by airborne multifrequency microwave radiometer - Lauri Kurvonen; Martti Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1996)

Backscattering properties of boreal forests at the C- and X-bands - Jouni Pulliainen; Kari J. M. Heiska; Juha Hyyppä; Martti Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1994)

A helicopter-borne eight-channel ranging scatterometer for remote sensing. I. System description - Martti Hallikainen; Juha Hyyppä; Juhani Haapenen; Teemu Tares; Pekka Ahola; Jouni Pulliainen; Martti Toikka (IEEE Trans. Geosci. Remote. Sens., 1993)

A helicopter-borne eight-channel ranging scatterometer for remote sensing. II. Forest inventory - Juha Hyyppä; Martti Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1993)

Development of geophysical retrieval algorithms for the MIMR - Jouni Pulliainen; Juha-Petri Kärnä; Martti Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1993)

Comparison of algorithms for retrieval of snow water equivalent from Nimbus-7 SMMR data in Finland - Martti T. Hallikainen; Petri A. Jolma (IEEE Trans. Geosci. Remote. Sens., 1992)

The theory and mechanical realization of an ideal scanning method for a single-channel imaging microwave radiometer - Martti Kemppinen; Martti T. Hallikainen (IEEE Trans. Geosci. Remote. Sens., 1992)