Whats the difference between slant range and ground range?
The time it takes for a transmitted signal to travel to an object and back tells you how far away the object is. If you transmit a signal and receive two separate “echoes”, you can use the time difference between when you record the first and second responses to determine the distance between the two sensed objects (dependent on where you stand). In this way the spaceborne SAR measures how far objects are from the spacecraft and the distance between the two objects, along the direction the spacecraft is looking. These distances are said to be recorded in slant range , since they are measured in a direction which is at an angle/slant to the ground. Often researchers don’t really care about distances from the spacecraft; they want to know about distances on the ground. Perhaps they need “real” (ground) distances to determine how much land was used for farming or what percentage of the sea was covered with ice, but the spacecraft samples the returning radar signals at specific time interv
