Image contrast can deteriorate significantly in scattering media, such as underwater, due to backscatter. This affects the performance of many computer vision techniques developed for open-air conditions, including the stereo matching algorithms, when applied to images acquired in these environments. It has been demonstrated that the backscatter field embodies depth information, thus can potent...

We have previously shown that high-frequency, high-resolution ultrasound can characterize the acoustic properties and composition of fatty plaques in cholesterol-fed rabbits. To determine whether quantitative ultrasound can delineate the regression of atherosclerotic lesions by detecting a change in their composition from fatty to fibrous types induced by alterations in dietary regimen, we fed ...

Coronary calcification is a potent predictor of cardiac events. In patients with chronic renal disease, both prevalence and intensity of coronary calcification are increased. It has remained uncertain whether it is the intima of the coronaries or the media that is calcified and whether the morphologic details of calcified plaques differ between renal and nonrenal patients. Autopsy samples of co...

The formation of cross-sectional images of biological tissues requires the discrimination between light conveying useful information—that is, propagating directly from object to image— from the abundant parasitic light caused by multiple scattering inherent to turbid media [1, 2]. In optical coherence tomography (OCT) [3], selective detection of light undergoing a single backscatter event (refl...

A theory is developed for generating short time, monostatic reverberation realizations caused by three-dimensionally distributed volume inhomogeneities in stratified media. A wave number integral approach to treating the propagation to and from the scatterers, combined with a two-dimensional spectral representation of the azimuthally averaged scatterer realizations and a novel numerical impleme...

Backscatter wireless communications have exceptionally stringent power constraints. This is particularly true for ambient backscatter systems, where energy and wireless carrier are both extracted from weak existing radio signals. The tight power constraints make it difficult to implement advanced coding techniques like spread spectrum, even though such techniques are effective in increasing the...

Short-range scatterometer systems are used to obtain radar backscatter signatures for understanding the interaction between electromagnetic energy and geophysical media in a number of remote sensing applications. Unlike long-range and intermediate-range radar systems, the sensitivity of short-range radars is not limited by thermal noise, but rather by reflections and leakage signals from the an...

The subject of scattering of electromagnetic waves by dense media has been one of intense interest in recent years. The present paper describes polarimetric backscatter measurements made at Ku-band on layers of a dense medium under very carefully controlled circumstances. The experiments have a dual purpose: 1) to evaluate the degree to which the experimental observations are predicted by theor...

We validated a canopy backscatter model for loblolly pine forest stands at the Duke Forest, North Carolina, by comparing the observed and modelled SAR backscatter from the stands. Given the SAR backscatter data calibration uncertainty, the model made good predictions of C-H H, C-HV, L-HH, L·HV, L-VV, P-HH, and P-HVbackscatter for most of 25 stands studied. The model overestimated C-VV backscatt...

This paper considers two specific types of experiments conducted to improve our understanding of radar backscatter from snow-covered ground surfaces. The first experiment involves radar backscatter measurements at Cand X-band of artificial snow of varying depths. The relatively simple target characteristics, combined with an exhaustive ground truth effort, make the results of this experiment es...