What is across-track scanner in remote sensing?
Across-track scanners scan the Earth in a series of lines. The lines are oriented perpendicular to the direction of motion of the sensor platform (i.e. across the swath). Each line is scanned from one side of the sensor to the other, using a rotating mirror (A).
What is meant by across-track scanning?
A whisk broom or spotlight sensor, also known as an across-track scanner, is a technology for obtaining satellite images with optical cameras. In a whisk broom sensor, a mirror scans across the satellite’s path (ground track), reflecting light into a single detector which collects data one pixel at a time.
Which of the following scanner records one line of an image simultaneously?
The pushbroom scanner or linear array sensor is a scanner without any mechanical scanning mirror but with a linear array of solid semiconductive elements which enables it to record one line of an image simultaneously, as shown is Figure 2.11. 1.
What are the different types of resolution in remote sensing?
In remote sensing we refer to three types of resolution: spatial, spectral and temporal. Spatial Resolution refers to the size of the smallest feature that can be detected by a satellite sensor or displayed in a satellite image. It is usually presented as a single value representing the length of one side of a square.
What is Pushbroom?
: a long-handled wide brush that is designed to be pushed and is used for sweeping.
What is difference between push broom scanner and whisk broom scanner?
Push broom scanners, also sometimes referred to as along track scanners, use a line of detectors arranged perpendicular to the flight direction of the spacecraft. A push broom scanner receives a stronger signal than a whisk broom scanner because it looks at each pixel area for longer.
What is the main function of a scanner?
A scanner is a device usually connected to a computer. Its main function is to scan or take a picture of the document, digitize the information and present it on the computer screen.
What are the 4 types of resolution?
Remotely sensed images are generated based on four different types of resolutions: