Polarimetric Workstation - Introduction

Polarimetry has started a new era with the recent launch of RADARSAT-2 and ALOS. That are equipped with fully polarimetric synthetic aperture radar (SAR). In contrast to RADARSAT-1, which measures only the one-dimensional projection of the received wave along the receiving antenna of linear horizontal polarization (H), polarimetric RADARSAT-2 and ALOS measure almost simultaneously the amplitude and phase of the reflected wave at the four possible combinations of transmitting and receiving antenna linear polarizations (HH, HV, VH, VV). This quadruple vector measure allows the user to synthesize the target radar return for any combination of transmitting-receiving antenna polarizations. This should permit a more complete characterization of the physical properties of the targets being illuminated by the radar wave.

In 1989, the Canada Centre for Remote Sensing (CCRS), Natural Resources Canada, was among the first institutions in the world to fly a polarimetric SAR. The polarimetric capabability was added to conventional dual polarization at X and C- band SARs on the Convair-580 aircraft in 1989, and 1990 (Livingstone et al. 1995). To promote the unique polarimetric capabilities of RADARSAT 2, CCRS has investigated various applications using fully polarimetric data collected by Convair-580 SARs. The results obtained depend significantly on the tools used for polarimetric information extraction. The CCRS polarimetric workstation (PWS) is the fruit of more then twenty years experience in polarimetric image analysis (Touzi and Charbonneau 2004). The heart of the PWS is based on the software developed twenty years ago by R. Touzi while he was research scientist in France (Touzi et al. 2002). PWS was firstly used at CCRS in 1991 to validate the calibration of Polarimetric Convair-580 X band. While R. Touzi was working at the College Militaire Royal de St Jean, part of the Fortran codes were then passed to C. Livingstone, and inserted in a package named Polsig. Polsig was used between 1992 and 1998 by many CCRS scientists for the development of polarimetric applications. In 2000, the software was updated and adapted to the GUI PC interface in Matlab environment. Since that, the PWS has been used intensively by CCRS for the promotion of RADARSAT2 polarimetric applications. In the context of the preparation of Canada to Radarsat2 mission, PWS was licensed to more than 20 institutions (governments, university, and industry) in Canada, and has been extensively used for the initiation in polarimetry, and development of new polarimetric applications. With the most recent launch of RADARSAT2 and ALOS, we have decided to upgrade the PWS for the analysis of RADARSAT2 and ALOS polarimetric C and L band SLC data.

PWS includes the most efficient set of tools selected from the wide set of tools published in the open literature. Extensive effort resulted in an efficient workstation that will help users in the the learning and exploration of the very promising and exciting technique of polarimetry. Our objective is to maintain PWS updated with the edge leading tools. This version includes in particular the Touzi decomposition (Touzi 2007, 2009), which is becoming among the standard tools for optimum polarimetric information extraction. It also include the Touzi SSCM (Touzi and Charbonneau, 2002), which was introduced for the optimum use of symmetric scattering information. This method was shown to be very promising for ship classification (Touzi et al., 2004)

PWS can ingest data coming from various polarimeters, such as Radarsat2, ALOS, the Convair-580 SAR, as well as SIR-C and the NASA-JPL AIRSAR. PWS offers the possibility to calibrate ALOS for Faraday rotation errors. With the increasing cycle of solar activity, Faraday rotation contamination has to be removed for meaningful exploitation of fully polarimetric ALOS-PALSAR data.

1. Requirements

Operating System: Windows XP Pro.

CPU : P4 3.0 GHz ( tested)

RAM : 1Gb min., 2Gb . suggested

Hard Disk :

560 MB Full installation with sample images
220 MB Full installation without samples images
30 MB Base installation without demo movie and sample images

2. Installation

1. Double-click on PWS_Setup.exe on the PWS CD
2. Double-click on MRCInstaller to install Matlb Library
3. Reboot the system

Be sure that PWS users have the security permission to read\write in the PWS folder and sample data folder.

Warning: If execution problem, DO NOT COPY .dll files in your \winnt\system32 folder. PWS will not run correctly and it will be very difficult to fix it.