Remote Sensing Systems—Platforms and Sensors

Abstract

This chapter provides an exhaustive overview of the remote sensing satellites, sensors, and their characteristics. First, the chapter provides definition and an understanding of remote sensing from best known sources. This common understanding is required for any student and practitioner of remote sensing. Second, the principles of EMS are enumerated. Third, the spatial, spectral, radiometric, and temporal resolutions are explained. Fourth, more than 18,000 satellites have been launched and operated by various governments and private enterprises from the mid-1950s to the present. The characteristics of many of the important satellite and sensor systems have been described. Fifth, remote sensing is both active and passive and is gathered in various EMSs such as the visible, NIR, shortwave infrared, mid-infrared (MIR), TIR, microwave, and radio waves (high-frequency waves). Radar, SAR, LiDAR, SONAR, and SODAR technologies operate with microwave and radio wave region of the EMS, while optical and hyperspectral imaging operates with visible to TIR region of EMS. The importance of gathering these data across such a wide range of EMS has been highlighted. Sixth, remote sensing data gathering is done in various modes such as nadir, off nadir, hyperspatial, hyperspectral, and multispectral. All of these have various implications on what we study and the level of these accuracies as a result of such acquisitions. This aspect has been implied throughout the chapter. Seventh, remote sensing data are gathered in various platforms: ground based, platform mounted, airborne, spaceborne, undersea, and UAV. The chapter focuses on spaceborne but does discuss several other platforms. Reading through these sections, it becomes clear that remote sensing has truly evolved in both sensor design and acquisition platforms. Eighth, the chapter provides a window into what to expect in near future through upcoming newer satellites and sensors. Ninth, the evolution of microsatellites has been highlighted. Like miniaturization of computing technology, satellites and sensors are undergoing revolutionary technological innovations, which make them provide smaller, cheaper, and yet better-quality data. Tenth, the chapter captures in a nutshell key developments in remote sensing from 1858 to the present and provides a glimpse on where the future of remote sensing satellites, sensors, and data are headed.

Topics & Concepts