Far-field intensities of light scattered from a linear centro-symmetric array illuminated by a plane wave of incident light are estimated at a series of detector angles. The intensities are computed from the superposition of E-fields scattered by the individual array elements. An average scattering phase function is used to model the scattered fields of individual array elements. The nature of scattering from the array is investigated using an image ( plot) of the far-field intensities computed at a series of locations obtained by rotating the detector angle from 0° to 360°, corresponding to each angle of incidence in the interval [0° 360°]. The diffraction patterns observed from the plot are compared with those for isotropic scattering. In the absence of prior information on the array geometry, the intensities corresponding to pairs satisfying the Bragg condition are used to estimate the phase function. An algorithmic procedure is presented for this purpose and tested using synthetic data. The relative error between estimated and theoretical values of the phase function is shown to be determined by the mean spacing factor, the number of elements, and the far-field distance. An empirical relationship is presented to calculate the optimal far-field distance for a given specification of the percentage error.
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