| 摘要 |
An improved method is provided for phase unwrapping in coherent imaging systems which use two complex images to form an interferogram. In the improved metho d, the interferogram of phase differences is divided into a relatively large plurality of transform blocks, wherein each transform block comprises a matrix of o x p data sample s, with o and p = 2" + 1, and n being an integer greater than 2. Further, adjacent transfo rm blocks are preferably defined to partially overlap. The wrapped phase values of adjacen t data samples within each transform block are then compared and if the difference therebetween exceeds a predetermined value, the entire block of data samples may be discarded for further use. Data samples of the retained transform blocks are then unwrapped to obtain phase values via an unweighted, least-squares technique implemented by Fast Fourier Transform . Using a known height value corresponding with a single data sample, an integration constant can be determined for a corresponding first transform block. Path-following may the n be used to determine an integration constant for the other retained transform blocks. T he phase values and integration constants may then be employed to determine height values fo r the interferogram. The disclosed method yields enhanced accuracy with reducedcom putational burden.
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