# Phase unwrapping for large SAR interferograms: statistical segmentation and generalized network models

@article{Chen2002PhaseUF, title={Phase unwrapping for large SAR interferograms: statistical segmentation and generalized network models}, author={Curtis W. Chen and Howard A. Zebker}, journal={IEEE Trans. Geosci. Remote. Sens.}, year={2002}, volume={40}, pages={1709-1719} }

Two-dimensional (2-D) phase unwrapping is a key step in the analysis of interferometric synthetic aperture radar (InSAR) data. While challenging even in the best of circumstances, this problem poses unique difficulties when the dimensions of the interferometric input data exceed the limits of one's computational capabilities. In order to deal with such cases, we propose a technique for applying the statistical-cost, network-flow phase-unwrapping algorithm (SNAPHU) of Chen and Zebker (2001) to…

## 535 Citations

### Phase Unwrapping for Very Large Interferometric Data Sets

- PhysicsIEEE Transactions on Geoscience and Remote Sensing
- 2011

The proposed method is able to efficiently unwrap very large interferometric data sets using limited computing resources and the globality of phase unwrapping solutions can be guaranteed.

### Phase unwrapping algorithm using edge detection and statistical cost functions

- Computer Science
- 2012

Efforts have been made during the current research work to generate a new algorithm, which relies on the SNAPHU solver routine and at the same time improves results by enhancing cost-functions with additional parameters.

### Edgelist phase unwrapping algorithm for time series InSAR analysis.

- Environmental ScienceJournal of the Optical Society of America. A, Optics, image science, and vision
- 2010

It is shown that, similar to the MCF network problem, the edgelist formulation also exhibits total unimodularity, which enables the integer program problem by using efficient linear programming tools.

### Joint phase unwrapping for multi-frequency SAR Interferometry

- Physics
- 2014

An important step in the interferometric processing chain is the phase unwrapping,
which transforms the ambiguous phase (wrapped in the interval -/+ 180°) in
an unambiguous phase. This unambiguous…

### An N-Dimensional Recurrent Noisy Phase Unwrapping Algorithm

- Physics
- 2007

One-dimensional (1-D) recurrent phase unwrapping algorithm is used to eliminate phase discontinuities in N-dimensional complex arrays and the problem of phase filtration and its effect on recurrent algorithm behavior is considered.

### New Advances of the Extended Minimum Cost Flow Phase Unwrapping Algorithm for SBAS-DInSAR Analysis at Full Spatial Resolution

- Environmental ScienceIEEE Transactions on Geoscience and Remote Sensing
- 2011

We present an efficient space-time phase unwrapping (PhU) algorithm that allows us to process sequences of multitemporal full resolution differential synthetic aperture radar (SAR) interferograms for…

### A Fast Phase Unwrapping Method for Large-Scale Interferograms

- Computer ScienceIEEE Transactions on Geoscience and Remote Sensing
- 2013

The proposed approach is not only efficient in solving large-scale PU problems but also effective in avoiding the inconsistency between local and global PU results generated by image tiling.

### Three-Dimensional Phase Unwrapping for Satellite Radar Interferometry, I: DEM Generation

- Environmental ScienceIEEE Transactions on Geoscience and Remote Sensing
- 2014

A 3-D unwrapping approach using an extended Kalman filter that readily exploits existing information, is robust in the presence of noise, and provides improved accuracy compared to existing approaches is described.

### Exploitation of SRTM DEM in InSAR phase unwrapping problem

- PhysicsIEEE 10th INTERNATIONAL CONFERENCE ON SIGNAL PROCESSING PROCEEDINGS
- 2010

A novel approach to exploit the Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) in the interferometric synthetic aperture radar (InSAR) data processing by introducing the SRTM DEM as guidance for phase unwrapping.

### Phase Unwrapping of Multi-Channel Synthetic Aperture Radar: Application to the TanDEM-X Mission

- Environmental Science
- 2015

The contribution of this thesis is the design and development of a new method which combines bistatic high-resolution interferometric data in order to perform a correct and accurate phase unwrapping…

## 29 References

### Two-dimensional phase unwrapping with use of statistical models for cost functions in nonlinear optimization.

- Computer ScienceJournal of the Optical Society of America. A, Optics, image science, and vision
- 2001

This work develops a maximum a posteriori probability (MAP) estimation approach for interferometric radar techniques, and derives an algorithm that approximately maximizes the conditional probability of its phase-unwrapped solution given observable quantities such as wrapped phase, image intensity, and interferogram coherence.

### A novel phase unwrapping method based on network programming

- PhysicsIEEE Trans. Geosci. Remote. Sens.
- 1998

A new phase unwrapping method is described and tested, which starts from the fact that the phase differences of neighboring pixels can be estimated with a potential error that is an integer multiple of 2/spl pi/.

### A two-dimensional region growing least squares phase unwrapping algorithm for interferometric SAR processing

- PhysicsIEEE Trans. Geosci. Remote. Sens.
- 1999

This paper presents a new two-dimensional (2-D) phase unwrapping (PhU) algorithm based on a least squares (LS) region growing strategy: the wrapped phase image is partitioned in different regions…

### Network approaches to two-dimensional phase unwrapping: intractability and two new algorithms.

- Computer ScienceJournal of the Optical Society of America. A, Optics, image science, and vision
- 2000

This work uses network constructions to show that the so-called minimum L0-norm problem is NP-hard, or one that complexity theory suggests is impossible for efficient algorithms to solve exactly, and presents two new algorithms for finding approximate solutions.

### A region-growing algorithm for InSAR phase unwrapping

- PhysicsIEEE Trans. Geosci. Remote. Sens.
- 1999

This paper describes a new region-growing algorithm for interferometric synthetic aperture radar (SAR) phase unwrapping that can unwrap well into low coherence regions, while making few ambiguity-level errors.

### Satellite radar interferometry: Two-dimensional phase unwrapping

- Environmental Science, Mathematics
- 1988

Interferometric synthetic aperture radar observations provide a means for obtaining high-resolution digital topographic maps from measurements of amplitude and phase of two complex radar images. The…

### Two-dimensional phase unwrapping by quad-tree decomposition.

- PhysicsApplied optics
- 2001

A new phase-unwrapping algorithm based on a two-step procedure is presented that can be used with and without quality masks and the error-minimizing step can use different norms, a full class of unwrapping algorithms can be implemented by this approach.

### Topographic mapping from interferometric synthetic aperture radar observations

- Environmental Science, Geology
- 1986

Interferometric synthetic aperture radar observations provide a means for obtaining high-resolution topographic terrain maps from data acquired simultaneously at two slightly displaced antennas.…

### Mapping small elevation changes over large areas: Differential radar interferometry

- Environmental Science
- 1989

A technique that uses synthetic aperture radar (SAR) images to measure very small (1 cm or less) surface motions with good resolution (10 m) over large swaths (50 km) is presented along with…

### Robust two-dimensional weighted and unweighted phase unwrapping that uses fast transforms and iterative methods

- Physics
- 1994

This work has developed a robust method (not based on any path-following scheme) for unwrapping 2D phase principal values (in a least-squares sense) by using fast cosine transforms.