An $O(N^3)$ algorithm for the calculation of far field radiation patterns

Travis Garrett

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arXiv · 1311.0854

An $O(N^3)$ algorithm for the calculation of far field radiation patterns

Travis Garrett

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Abstract

We present a new method for computing the Near-To-Far-Field (NTFF) transformation in FDTD simulations which has an overall scaling of $O(N^3)$ instead of the standard $O(N^4)$. By mapping the far field with a cartesian coordinate system the 2D surface integral can be split into two successive 1D integrals. For a near field spanned by $N_X \times N_Y$ discrete sample points, and a far field spanned by $N_θ \times N_ϕ$ points, the calculation can then be performed in $O(N_θN_X N_Y) + O(N_θN_ϕN_Y)$ operations instead of $O(N_θN_ϕN_X N_Y)$.

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Travis Garrett. 2013-11-04. An $O(N^3)$ algorithm for the calculation of far field radiation patterns. https://arxiv.org/abs/1311.0854

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