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Title: Polar format algorithm : survey of assumptions and approximations.

Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
Report Number(s):
DOE Contract Number:
Resource Type:
Technical Report
Country of Publication:
United States

Citation Formats

Musgrove, Cameron. Polar format algorithm : survey of assumptions and approximations.. United States: N. p., 2012. Web. doi:10.2172/1059472.
Musgrove, Cameron. Polar format algorithm : survey of assumptions and approximations.. United States. doi:10.2172/1059472.
Musgrove, Cameron. 2012. "Polar format algorithm : survey of assumptions and approximations.". United States. doi:10.2172/1059472.
title = {Polar format algorithm : survey of assumptions and approximations.},
author = {Musgrove, Cameron},
abstractNote = {},
doi = {10.2172/1059472},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2012,
month =

Technical Report:

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  • SAR phase history data represents a polar array in the Fourier space of a scene being imaged. Polar Format processing is about reformatting the collected SAR data to a Cartesian data location array for efficient processing and image formation. In a real-time system, this reformatting or ''re-gridding'' operation is the most processing intensive, consuming the majority of the processing time; it also is a source of error in the final image. Therefore, any effort to reduce processing time while not degrading image quality is valued. What is proposed in this document is a new way of implementing real-time polar-format processingmore » through a variation on the traditional interpolation/2-D Fast Fourier Transform (FFT) algorithm. The proposed change is based upon the frequency scaling property of the Fourier Transform, which allows a post azimuth FFT interpolation. A post azimuth processing interpolation provides overall benefits to image quality and potentially more efficient implementation of the polar format image formation process.« less
  • The purpose of this report is to provide a background to Synthetic Aperture Radar (SAR) image formation using the Polar Format (PFA) processing algorithm. This is meant to be an aid to those tasked to implement real-time image formation using the Polar Format processing algorithm.
  • Traditional polar format image formation for Synthetic Aperture Radar (SAR) requires a large amount of processing power and memory in order to accomplish in real-time. These requirements can thus eliminate the possible usage of interpreted language environments such as MATLAB. However, with trapezoidal aperture phase history collection and changes to the traditional polar format algorithm, certain optimizations make MATLAB a possible tool for image formation. Thus, this document's purpose is two-fold. The first outlines a change to the existing Polar Format MATLAB implementation utilizing the Chirp Z-Transform that improves performance and memory usage achieving near realtime results for smaller apertures.more » The second is the addition of two new possible image formation options that perform a more traditional interpolation style image formation. These options allow the continued exploration of possible interpolation methods for image formation and some preliminary results comparing image quality are given.« less
  • Limitations on focused scene size for the Polar Format Algorithm (PFA) for Synthetic Aperture Radar (SAR) image formation are derived. A post processing filtering technique for compensating the spatially variant blurring in the image is examined. Modifications to this technique to enhance its robustness are proposed.
  • The purpose of this project was to review and assess existing Federal Government Building Standards, retrofit implementation plans and develop uniform and consistent buildings survey guidelines and criteria for use by all Federal agencies in the conduct of their buildings survey actions in support of the Federal Energy Management Program. The contractor will also develop survey evaluation techniques and methodology to be utilized by the Federal Energy Administration in the evaluation of Federal agency survey results and prioritization and selection of optimum sets of buildings retrofit projects. The study assumptions and criteria involved in designing a document to aid Federalmore » agencies in identifying energy conserving building retrofit programs are itemized and discussed. (LCL)« less