Jingqi Kay Liu

Synthetic Aperture, Over-the-Horizon

Synthetic Aperture Radar (SAR) is a remote sensing technology that uses radar to create high-resolution images of the Earth’s surface. Unlike optical sensors, SAR can operate under any weather conditions, regardless of day or night, since it does not rely on visible lights to observe and capture Earth’s conditions.

SAR utilizes microwave frequencies, providing the ability to penetrate clouds and vegetation, making it valuable for applications such as terrain mapping, environmental monitoring, and disaster management. The technology captures reflections of radar signals to construct detailed and three-dimensional images of the Earth’s surface.

While optical imaging technology used in Landsat captures light reflected from the subject’s surface passively, SAR actively emits radar signals and constantly calculates information based on the way their return and diffusion patterns. It allows SARs to be highly selective with their subject, area of interest, and level of resolution.