λ i Clutter spatial density.
Nevertheless, the impact of spatial distribution of clutter points is not easy to estimate.
Monostatic airborne radar with sidelooking array antennas has the desirable property that the relationship between the clutter spatial and Doppler frequencies is both linear and range invariant, i.e., clutter is stationary, thereby enabling its effective suppression using training data from adjacent ranges.
We found no association between other CEUS parameters and MVD; this is might be because AT, TTP, WIT, and ascending slope are time-dependent parameters, represented the enhanced speed of the tumor, which might related to spatial distribution of clutter, vascular uneven thickness, distorting, and arteriovenous fistula formation happened in neoangiogenesis, but not number of microvessels.
However, in many practical applications, for example, monostatic airborne radar with non-sidelooking arrays [4], cylindrical arrays [5], conformal arrays [6], and bistatic airborne radar [7], the clutter spatial-Doppler frequency relationship becomes nonlinear and range dependent, especially at short range, i.e., clutter is non-stationary.
The parameter λ denotes the spatial density of the clutter and new targets, which is a design parameter.
The sum of the data terms corresponds to the sum of the outputs of different correlation filters matched to each of the possible (fixed) target templates taking into account the spatial correlation of the clutter background.
Moving target detection in SAR image is a difficulty, because the slowly moving target may be totally submerged among the main-beam clutter in spatial, time, and frequency domain.
For each of these, we added a component to the salience model, including richer interactions among orientation-tuned units, both at spatial short range (for clutter reduction) and long range (for contour facilitation), and a detailed model of eccentricity-dependent changes in visual processing.
The proposed algorithm enables integrated, multiframe target detection and tracking incorporating the statistical models for target motion, target aspect, and spatial correlation of the background clutter.
