Remote Sensing Terminology
The Landsat program is a series of American satellites that use the visible and infrared parts of the spectrum to record images of the Earth's surface. It is the longest running enterprise for acquisition of satellite imagery, and started back in 1972. The most recent, Landsat 8, was launched in 2013.
Landsat satellites are located in a polar orbit, which allows them to provide images of almost all of the Earth's geography. As the satellite orbits the Earth from pole to pole, it appears to move from east to west because of the Earth’s rotation. This apparent movement allows the satellite to view a new area with each orbit.
Determining land cover has become one of the most common uses of Landsat Imagery and remotely sensing generated images all around the world.
The LiDAR sensor produces a series of point measurements that consists of geographic location (X & Y) and height (Z) of both natural and man-made features, and can be further processed to produce several different products and integrated into a Geographic Information System (GIS).
Click here to learn more about LiDAR
The amount of energy returning to the sensor (known as backscatter) is dependent upon the topography, roughness, and dielectric properties (moisture). Areas of an image with low backscatter appear dark (such as water), while areas of high backscatter appear as light gray levels approximating white shades. By interpreting the various gray tones, textures and patterns, the user can detect information regarding to the regions geologic lithology and structure.
In much of remote sensing, the process involves an interaction between incident radiation and the targets of interest. This is exemplified by the use of imaging systems where the following seven elements are involved. Note, however that remote sensing also involves the sensing of emitted energy and the use of non-imaging sensors. Click here to learn more about Remote Sesning
Submit a term
Download Canadian OpenData from over 100 different Sources
Brief Review of the Leica GS20 PDM GPS Sensor & GIS DataPro Processing Software
The Leica GS20 PDM (professional Data Mapper) handheld GPS unit was a small GPS device that was included with the RTK GPS unit that was purchased for my LIDAR research project at the AGRG in 2003.
“The GS20 PDM combines the simplicity of a recreational GPS with the power and flexibility of a professional grade mapping system. Providing you with a true turn-key GPS mapping solution, the GS20 PDM is a GPS receiver, antenna, and data collector, all in an ergonomic handheld. With the GS20 PDM, powerful functionality doesn’t mean difficult to use. The menu-driven interface and graphical map display make it easy to learn so field crews can start collecting data right away.”
The unit itself was a well designed, quality built weather proof GPS instrument, (much similar to the Trimble one that we had), but did not get much use mainly due to the fact that we had plenty of GPS gear available most of the time and my project required the more accurate equipment. Some of the other research projects used these units most of the time.
The GS20 did not come with very good user guides so Jonathan and I created a brief user guide for the group. The user guide covers the basics needed to use the device for data collection, such as how to create a code list, importing way-points, downloading data etc.
At the time there was not much material available online but since that time plenty of other guides have been created so I have included a few links to ones that we found useful.