The principles of SAR interferometry, in particular phase unwrapping and geocoding, are described. Interferometric point positioning is treated based on a least squares approach avoiding approximations. Current issues of SAR interferometry are discussed: atmospheric effects on spaceborne repeat-pass interferometry limiting the accuracy and reliability of Digital Elevation Models (DEM), the Shut...

This paper presents a fast, highly sensitive and low-cost tapered optical fiber biosensor that enables the label-free detection of biomolecules. The sensor takes advantage of the interference effect between the fiber's first two propagation modes along the taper waist region. The biomolecules bonded on the taper surface were determined by demodulating the transmission spectrum phase shift. Beca...

In this paper, we describe guided-mode resonance biochemical sensor technology. We briefly discuss sensor fabrication and show measured binding dynamics for example biomaterials in use in our laboratories. We then turn our attention to a particularly powerful attribute of this technology not possessed by competing methods. This attribute is the facile generation of multiple resonance peaks at a...

SAR polarimetry makes use of the polarization dependent scattering response of each pixel within the imaged area. The polarimetric response is highly sensitive to the scattering mechanism of a pixel. SAR interferometry is sensitive to the location of a pixel and its scattering geometry. The location of a pixel can be measured by the phase difference between two coherent SAR images using SAR int...

Source-receiver interferometry allows Green's functions between sources and receivers to be estimated by means of convolution and cross-correlation of other wavefields. Source-receiver interferometry has been observed to work surprisingly well in practical applications when theoretical requirements (e.g., complete enclosing boundaries of other sources and receivers) are contravened: this paper ...

Interferometry allows for synthesis of data recorded at any two receivers into waves that propagate between these receivers as if one of them behaves as a source. This is accomplished typically by crosscorrelations. Based on perturbation theory and representation theorems, we show that interferometry also can be done by deconvolutions for arbitrary media and multidimensional experiments. This i...

Synthetic aperture radar (SAR) interferometry uses the phase difference between two SAR antennas to obtain an elevation estimate of the imaged terrain. Using an initial digital elevation model (DEM), the time-domain backprojection algorithm implicitly removes the terrain height phase from images during image formation. The use of a DEM during image formation adds additional information to the p...

The phrase virtual source refers to two different techniques in this dissertation. In the first half of the dissertation, it refers to interferometry and in the second half it uses the concept of the synthetic aperture technique. In interferometry, a receiver is converted to a “virtual source”. In the synthetic aperture technique, a large “virtual source” is constructed by adding small sources....

The largest limitation of phase-shifting interferometry for optical testing is the sensitivity to the environment, both vibration and air turbulence. In many situations the measurement accuracy is limited by the environment and sometimes the environment is sufficiently bad that the measurement cannot be performed. Recently there have been several advances in dynamic interferometry techniques fo...