Near-Field/Far-Field Transformation with Helicoidal Scanning from Irregularly Spaced Data

Near-field — Far-field Transformation Technique with Helicoidal Scanning for Elongated Antennas

A fast and accurate near-field — far-field transformation technique with helicoidal scanning is proposed in this paper. It is tailored for elongated antennas, since a prolate ellipsoid instead of a sphere is considered as surface enclosing the antenna under test. Such an ellipsoidal modelling allows one to consider measurement cylinders with a diameter smaller than the antenna height, thus redu...

Estimating fractal dimension of natural terrain from irregularly spaced data

Multiresolution Analysis Adapted to Irregularly Spaced Data

This paper investigates the mathematical background of multiresolution analysis in the specific context where the signal is represented by irregularly sampled data at known locations. The study is related to the construction of nested piecewise polynomial multiresolution spaces represented by their corresponding orthonormal bases. Using simple spline basis orthonormalization procedures involves...

Irregularly Spaced Time Series Data with Time Scale Measurement Error

This project can be mainly divided into two sections. In the first section it attempts to model an irregularly spaced time series data where time scale is being measured with a measurement error. Modelling an irregularly spaced time series data alone is quite challenging as traditional time series techniques only capture equally/regularly spaced time series data. In addition to that, the measur...

A test for stationarity for irregularly spaced spatial data

Abstract The analysis of spatial data is based on a set of assumptions, which in practice need to be checked. A commonly used assumption is that the spatial random field is second order stationary. In this paper, a test for spatial stationarity for irregularly sampled data is proposed. The test is based on a transformation of the data (a type of Fourier transform), where the correlations betwee...