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A numerical technique is presented which yields an exact solution to the one-dimensional scattering problem. The algorithm is used to compute phase shift error curves associated with the WKB approximation. A variety of scattering potentials are considered and cover cases for which the WKB solution varies from extremely good to poor. It is shown that some commonly assumed forms for ionospheric e...

Sparse representation (SR) algorithms can be implemented for high-resolution direction of arrival (DOA) estimation. Additionally, SR can effectively separate the coherent signal sources because the spectrum estimation is based on the optimization technique, such as the L(1) norm minimization, but not on subspace orthogonality. However, in the actual source localization scenario, an unknown gain...

In this contribution, we investigate the effect of carrier phase errors on the performance of orthogonal frequency division multiplexing (OFDM) and multicarrier code-division multiple access (MC-CDMA). We show that OFDM and MC-CDMA have essentially the same sensitivities to carrier phase errors. A constant carrier phase offset yields no degradation of the system performance. We show that OFDM a...

Polarization based interferometers for single snap-shot measurements allow single frame, quantitative phase acquisition for vibration insensitive measurements of optical surfaces and have been successfully used on a variety of interferometer types. This technique generally involves the simultaneous acquisition of three or more images on the same camera or multiple cameras, which are phase shift...

The mapping of complex-valued functions onto phase-only spatial light modulators is examined. Random phase encoding effectively adds amplitude control to the phase-only filter and can be used to trade off systematic errors of the phase-only filter for random errors. This is illustrated for the problem of recognizing a threedimensional object from arbitrary views. The complex-valued composite fi...

To focus a synthetic-aperture radar image that is suffering from phase errors, a phase-error estimate is found that, when it is applied, maximizes the sharpness of the image. Closed-form expressions are derived for the gradients of a sharpness metric with respect to phase-error parameters, including both a point-by-point (nonparametric) phase function and coefficients of a polynomial expansion....

The largest existing optical telescopes and the next generation of extremely large telescopes are all segmented telescopes. The primary mirror segments must be phased in order to attain the diffraction limit of the telescope. In this paper, we investigate the effect of phasing errors on image quality delivered by the adaptive optics systems at the W. M. Keck Observatory using both simulations a...