tailieunhanh - Environmental Modelling with GIs and Remote Sensing - Chapter 3

Cảm biến từ xa có thể được định nghĩa là việc mua lại dữ liệu vật lý của một đối tượng với một bộ cảm biến mà không có tiếp xúc trực tiếp với các đối tượng chính nó. Nhiếp ảnh bề mặt của trái đất ngày quay trở lại đầu những năm 1800, khi trong 1839 Louis Daguerre công khai báo cáo kết quả của các hình ảnh từ các thí nghiệm chụp ảnh. Năm 1858 nhìn từ một quả bóng trên không đầu tiên được sản xuất vào năm 1910 Wilber Smith thử nghiệm máy bay có được. | 3 New environmental remote sensing systems F. van der Meer . Schmidt w. Bakker and w. Bijker INTRODUCTION Remote sensing can be defined as the acquisition of physical data of an object with a sensor that has no direct contact with the object itself. Photography of the Earth s surface dates back to the early 1800s when in 1839 Louis Daguerre publicly reported results of images from photographic experiments. In 1858 the first aerial view from a balloon was produced and in 1910 Wilber Smith piloted the plane that acquired motion pictures of Centocelli in Italy. Image photography was collected on a routine basis during both world wars during World War II non-visible parts of the electromagnetic EM spectrum were used for the first time and radar technology was introduced. In 1960s the first meteorological satellite was launched but actual image acquisition from space dates back to earlier times with various spy satellites. In 1972 with the launch of the earth observation land satellite Landsat 1 renamed from ERTS-1 repetitive and systematic observations were acquired. Many dedicated earth observation missions followed Landsat 1 and in 1980 NASA started the development of high spectral resolution instruments hyperspectral remote sensing covering the visible and shortwave infrared portions of the EM spectrum with narrow bands allowing spectra of pixels to be imaged Goetz et al. 1985 . Simultaneously in the field of active microwave remote sensing research led to the development of multi-polarization radar systems and interferometric systems Massonnet et al. 1994 . The turn of the millennium marks the onset of a new era in remote sensing when many experimental sensors and system approaches will be mounted on satellites thereby providing ready access to data on a global scale. Interferometric systems will provide global digital elevation models while spaceborne hyperspectral systems will allow detailed spectrophysical measurements at almost any part of the earth s .