Phase Unwrapping [duplicate]

1. What does phase unwrapping mean?
2. What is phase unwrapping SAR?
3. What is wrapped and unwrapped phase?
4. Why do we need phase unwrapping?

What does phase unwrapping mean?

Phase unwrap or unwrap is a process often used to reconstruct a signal's original phase. Unwrap algorithms add appropriate multiples of 2π to each phase input to restore original phase values, as illustrated in the diagram.

What is phase unwrapping SAR?

Phase unwrapping is the key problem in building the elevation map of a scene from interferometric synthetic aperture radar (SAR) system data. Phase unwrapping consists in the reconstruction of the phase difference of the radiation received by two SAR systems as a function of the azimuth and slant range coordinates.

What is wrapped and unwrapped phase?

When φ(t) is constrained to its principal value, either the interval (−π, π] or [0, 2π), it is called wrapped phase. Otherwise it is called unwrapped phase, which is a continuous function of argument t, assuming s_a(t) is a continuous function of t.

Why do we need phase unwrapping?

Phase unwrapping is needed to make the distribution of phase continuous. Unwrapping requires knowledge of the fringe sign and the phase of the starting point. In the unwrapping function shown below, the fringe sign is set to monotonically increase from right to left of the starting point which has zero phase.