Azimuth - Direction aligned with the relative spaceborne platform velocity vector.
Detection - Processing step in which the phase information is removed and only the signal amplitude is preserved. Normally the detection uses a magnitude squared method and has units of voltage square per pixel.
Focusing - Data processing finalized to focus the SAR image in range and azimuth through bidimensional signal compression.
Ground range - Projection of the slant range into the ground.
Incidence angle - Local incidence angle on ground calculated using the ellipsoidal Earth model.
Looks - The number of lower resolution images (using only a subset of the full collected spectrum) used to form the complete image. Individual looks are first ‘Detected’ and then averaged together. This can be performed in either the range or azimuth dimension and is normally used to reduce the speckle noise from SAR images. (called multi-looking).
Range - Direction orthogonal to the satellite velocity.
Slant range vector - Line-of-Sight vector between the satellite’s antenna and the target on ground.
Slant range plane - Plane containing the relative sensor velocity vector and the slant range vector for a given target.
Spotlight - In the spotlight acquisition mode the spacecraft is mechanically steered to increase the integration time over a fixed target. The increased integration time allows a finer azimuth resolution to be attained.
Stripmap - In the stripmap acquisition mode the antenna beam has a fixed pointing direction with respect to the platform; the beam direction forms an angle with the vertical passing by the satellite, defined elevation angle.