International Archives of Photogrammetry and Remote Sensing, Vol. 32, Part 7-4-3 W6, Valladolid, Spain, 3-4 June, 1999 
ANISOTROPY INFORMATION FROM MOMS-02/PRIRODA STEREO DATASETS - AN ADDITIONAL PHYSICAL 
PARAMETER FOR LAND SURFACE CHARACTERISATION 
Th. Schneider 1 ,1. Manakos 1 , Peter Reinartz 2 , R. Muller 2 
1 Institute for Land Use Planning and Nature Conservation, University of Munich, Am Hochanger 13, D-85354 Freising, e- 
mail:Tomi.Schneider@lrz.uni-muenchen.de, Ioannis.Manakos@lrz.uni-muenchen.de 
2 Institute for Optoelectronics, Postfach 1116, D-82230 Wessling, e-mail: Peter.Reinartz@dlr.de, Rupert.Mueller@dlr.de 
KEYWORDS: MOMS-2P, Stereo Data, Anisotropy of Backscatter, Angular Signature, BRDF, Radiometric Correction. 
ABSTRACT 
Multispectral and stereo band evaluations of mode D data (Blue, NIR, Pan fore and aft) from the M0MS-2P mission on MIR are 
presented. Along-track MOMS-02 stereo datasets are observations of the earth surface from three distinct view directions with the 
same illumination conditions. MOMS-02 mode D data allows to investigate three out of five signature types known in remote 
sensing: spatial, spectral and angular signatures. The remotely sensed signal is always a combination of these three signature types. 
Visual as well as computer based analysis indicates, that the result of multispectral and anisotropy based classification is determined 
by different biophysical parameters. In case of vegetation, the spectral approach explores mainly the absorption of incoming radiation 
by pigments and water, while the anisotropy information is due to stand structure and plant architecture. The synergistic potential of 
the combined use of multispectral and anisotropy information is pointed out by the increase of the classification accuracy for the 
combined multispectral and stereo bands evaluation. The results of visual interpretation led to the conclusion that a further 
substantial increase can be expected using common classification routines. 
For the retrieval of bio- and geo-physical parameters, the accurate radiometric correction is of decisive importance. Both, radiometric 
calibration of the sensor, as well as the correction for atmospheric attenuation, are to be performed before a quantitative data 
analysis. The method used for the radiometric calibration of the M0MS-2P CCD sensor lines used for multispectral and stereo data 
registration is presented and the results are briefly discussed. The correction for atmospheric attenuation of the stereo data is still 
under investigation. Due to differing illumination-to-sensor angle for the three view directions of a stereo dataset, each band is 
corrected individually. The problem is the correct estimation of aerosol type and aerosol scattering function determination. 
1. INTRODUCTION 
The paper presents an approach, which first became possible 
with quasi-simultaneous stereo datasets from the MOMS-02 
system: the analysis of angular signatures from space. For Earth 
observation, an additional physical parameter can be 
investigated. Combined with the well-known multispectral 
information, an increase in classification accuracy and status 
assessment, as well as improvements in relating the remotely 
sensed signal to bio- and geo-physical parameters of the 
surfaces of interest are expected. 
First investigations with a MOMS-02/D2 dataset from the 
Sinaloa district in Mexico with intensive cultivated crops and 
vegetables in flat terrain (Schneider et al., 1999) demonstrate 
the surprisingly high potential of the anisotropy approach. 
The presented paper investigates the approach in a Mid- 
European, flat to hilly landscape in Bavaria, 40 km North from 
Munich. Compared to the Mexico study, two key parameters are 
different: 
• MOMS-2P mode D consists of multispectral band 1 (blue) 
instead of 3 (red) (and bands 4 (NIR), 6 and 7, which were 
in both D2 and PRIRODA missions). 
• the illumination-to-sensor geometry is not favourable for 
angular signature extraction. 
The hypotheses of the presented investigations are as follows: 
• the anisotropy information of along-track stereo datasets can 
be used complementarity to multispectral data analysis. 
• the combined use of anisotropy and multispectral 
information increase classification accuracy and status 
assessment. 
Problems with CCT transport from the MIR space station to the 
base station in Oberpfaffenhofen, where the data were 
preprocessed, have led to a delay in data delivery. Under this 
circumstances the presented results are of preliminary character. 
The paper focuses on features that demonstrate the potential of 
the anisotropy approach by comparing results in direct 
competition to the multispectral approach. 
1.1. The MOMS-02 system 
MOMS-02 is the first representative of a new along-track sensor 
generation, designed for the combined stereo-photogrammetric 
and thematic mapping of earth’s surface. The Modular 
Optoelectronic Multispectral Stereo-scanner (MOMS-02) is a