The Amazon Radiography Project aims at producing maps in the scale of 1:50,000, in a area of 1,8 million km 2 of the Brazilian Amazon using PolInSAR data. The purpose of this paper is to present the actual status of the Amazon Radiography Project and its perspectives. Together, some examples of technical and logistic overcoming will be highlighted. The products that will be made available throughout the project are orthoimages (X-HH and P-HH-HV-VH-VV bands), digital surface and terrain models (DSM / DTM), topographic maps, geospatial databases and vegetation stratification. From 2008 until now 72% of the project area has been imaged and 48% of the cartographic products been made. During the project, the adversities encountered generated the need for methodological development such as SAR data processing, new backup politics and polarimetric calibration. Also, the project allowed the technological development of the Brazilian SAR industry with the construction of new sensors.

This paper analyses the use of an algorithm to estimate the unknown interferometric phase offsets without the use of ground control points or already calibrated data. Modifications in order to enhance the precision and robustness of the algorithm are presented and the new implementation is validated with X-band airborne SAR data. Furthermore, issues related with the use of the algorithm for P-band datasets are discussed and experimental results are shown for this kind of data. The stability of the algorithm according to the choice of the area of the image used for the estimation and to the choice of the coherence threshold is also verified for both X-and Pband data sets.

Este trabalho descreve o uso da técnica DInSAR (Interferometria Diferencial por Radar de Abertura Sintética), gerada com a Banda P, e da diferença entre modelos digitais de superfície (DSM), gerada com a Banda X, na detecção de movimentos do terreno causados por processos erosivos nas margens de Rio Madeira. A área de estudo caracterizou-se por um trecho de rio que se inicia no barramento da UHE Santo Antônio, no município de Porto Velho (Rondônia), e se estende até o município de Humaitá (Amazonas). A metodologia foi estabelecida a partir da comparação de séries temporais geradas pelo radar, com medições obtidas em campo. Os resultados apontaram um desempenho positivo desta tecnologia. Acredita-se, entretanto, que a utilização de métodos de processamento mais robustos pode melhorar a qualidade dos resultados. De qualquer forma, constata-se que esta aplicação já apresenta grande potencial para o monitoramento de movimentos da superfície do terreno em larga escala.

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The positional validation of datasets is an important step for cartography studies since it allows learning about its accuracy, and also indicates the data process quality. However, the positional validation of Synthetic Aperture Radar (SAR) datasets have some additional challenges when compared to optical images due to the geometric distortions. We employ existing targets such as traffic signs and lampposts in the scene and identify them on the image as control points. We performed the validation of the geographic coordinates used as planialtimetric positional control points, using both the amplitude backscattering orthoimage and the Digital Terrain Model (DTM) generated from the InSAR system. We employed the NMAS, ASPRS and NSSDA tests along with information by the Brazilian Standards. This validation showed these control points presented the following results for 1:10,000 scale: NMAS test - class “A” in PEC and PEC-PCD; ASPRS test - RMSE x = 1.317m, RMSE y = 1.231m and RMSE z = 1.145m; and NSSDA test - RMSE r = 1,802m, Precision r = 3.118m and Precision z = 2.244m. These results prove we can use the proposed targets as control points and the used InSAR datasets meet the expected quality for generation of geotechnic products for 1:10,000 scale.