The TUD Synthetic Aperture Radiometer demonstration model consists of a 2-channel X-band correlation radiometer with two horn antennas and an antenna mounting structure enabling the horns to be mounted in relevant positions within a certain aperture. The cross correlation of the signals from the 2 antennas produces a sample of the visibility function, which is the Fourier transform of the brigh...

In this paper we explore some novel aspects of visibility for stationary and moving points inside a simple polygon P . We provide a mechanism for expressing the visibility polygon from a point as the disjoint union of logarithmically many canonical pieces using a quadratic-space data structure. This allows us to report visibility polygons in time proportional to their size, but without the cubi...

A non-perturbative treatment is developed for the dephasing produced by the shot noise of a onedimensional electron channel. It is applied to two systems: a charge qubit and the electronic MachZehnder interferometer, both of them interacting with an adjacent partitioned electronic channel acting as a detector. We find that the visibility (interference contrast) can display oscillations as a fun...

We study the problem of visibility in polyhedral terrains in the presence of multiple viewpoints. We consider three fundamental visibility structures: the visibility map, the colored visibility map, and the Voronoi visibility map. We study the complexity of each structure for both 1.5D and 2.5D terrains, and provide efficient algorithms to construct them. Our algorithm for the visibility map in...

This paper presents a new approach to visibility culling. We propose a conservative visibility preprocessing method for complex virtual environments. The proposed method deals with general 3D graphical models and invisible polygons jointly blocked by multiple occluders. The proposed method decomposes volume visibility from the predefined volume into the area visibility from rectangles surroundi...

We report the first stage of a project aimed at computing visibility scripts for active inspection applications, in which a robot-mounted sensor observes a known object from different viewpoints. Visibility scripts describe the optimal sensor position for a given inspection task and may involve different visibility requirements, e.g. achieving optimal visibility of a single object feature or si...

Die selbständige und eigenhändige Anfertigung versichere ich an Eides statt. Conclusion 71 Bibliography 75 Introduction " The true mystery of the world is the visible, not the invisible. " Oscar Wilde How can geometric settings be encoded combinatorially? Which discrete structures extract the essential information from continuous arrangements? How can the combinatorial properties of visibility ...

Visibility computations are central in any computer graphics application. The most common way to reduce this expense is the use of approximate approaches using spatial subdivision. More recently analytic approaches efficiently encoding visibility have appeared for 2D (the visibility complex) and for certain limited cases in 3D (aspect graph, discontinuity meshes). In this paper we propose a new...

We present an online occlusion culling system which computes visibility in parallel to the rendering pipeline. We show how to use point visibility algorithms to quickly calculate a tight potentially visible set (PVS ) which is valid for several frames, by shrinking the occluders used in visibility calculations by an adequate amount. These visibility calculations can be performed on a visibility...