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Full-Text Articles in Engineering
Byu Micro-Sar: A Very Small, Low-Power Lfm-Cw Synthetic Aperture Radar, Michael Israel Duersch
Byu Micro-Sar: A Very Small, Low-Power Lfm-Cw Synthetic Aperture Radar, Michael Israel Duersch
Theses and Dissertations
Brigham Young University has developed a low-cost, light-weight, and low power consumption SAR for flight on a small unmanned aerial vehicle (UAV) at low altitudes. This micro-SAR, or uSAR, consumes only 18 watts of power, ideal for application on a small UAV. To meet these constraints, a linear frequency modulation-continuous wave (LFM-CW) transmit signal is utilized. Use of an LFM-CW signal introduces some differences from the typical strip map SAR processing model that must be addressed in signal processing algorithms. This thesis presents a derivation of the LFM-CW signal model and the associated image processing algorithms used for the uSAR …
Motion Compensation Of Interferometric Synthetic Aperture Radar, David P. Duncan
Motion Compensation Of Interferometric Synthetic Aperture Radar, David P. Duncan
Theses and Dissertations
Deviations from a nominal, straight-line flight path of a synthetic aperture radar (SAR) lead to inaccurate and defocused radar images. This thesis is an investigation into the improvement of the motion compensation algorithm created for the BYU inteferometric synthetic aperture radar, YINSAR. The existing BYU SAR processing algorithm produces improved radar imagery but does not fully account for variations in attitude (roll, pitch, yaw) and does not function well with large position deviations. Results in this thesis demonstrate that a higher order motion compensation algorithm is not as effective as using a segmented reference track, coupled with the current lower-order …
Speckle Denoising Using Wavelet Transforms And Higher-Order Statistics, Samuel Peter Kozaitis, Anurat Ingun
Speckle Denoising Using Wavelet Transforms And Higher-Order Statistics, Samuel Peter Kozaitis, Anurat Ingun
Electrical Engineering and Computer Science Faculty Publications
We reduced speckle noise in SAR imagery by retaining only those wavelet coefficients with significant third-order correlation coefficients. These coefficients were generated from the cross-correlation functions of the image and wavelet basis functions. Using this approach, we compared the results between directly applying our denoising method, and first preprocessing by taking the logarithm of an image. In our approach, we examined wavelet coefficients in an environment where the contribution from the second-order moment of the noise had been reduced.