Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Efficient Computation of Spatially-Discrete Traveling-Wave Modulated
  Structures   Traveling-wave modulation is a form of space-time modulation which has been
shown to enable unique electromagnetic phenomena such as non-reciprocity,
beam-steering, frequency conversion, and amplification. In practice,
traveling-wave modulation is achieved by applying a staggered time-modulation
signal to a spatially-discrete array of unit cells. Therefore, the capability
to accurately simulate spatially-discrete traveling-wave modulated structures
is critical to design. However, simulating these structures is challenging due
to the complex space-time dependence of the constituent unit cells. In this
paper, a field relation (referred to as the interpath relation) is derived for
spatially-discrete traveling-wave modulated structures. The interpath relation
reveals that the field within a single time-modulated unit cell (rather than an
entire spatial period) is sufficient to determine the field solution throughout
space. It will be shown that the interpath relation can be incorporated into
existing periodic method of moments solvers simply by modifying the source
basis functions. As a result, the computational domain is reduced from an
entire spatial period to a single time-modulated unit cell, dramatically
reducing the number of unknowns. In the context of traveling-wave modulation,
this enables researchers to efficiently simulate both complex structures with
patterned unit cells in addition to continuous structures with infinitesimal
unit cells.

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The categories of this paper are: quant-ph
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The categories of this paper are: econ
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
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The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
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The categories of this paper are: q-alg
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The categories of this paper are: dg-ga
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The categories of this paper are: cs
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The categories of this paper are: plasm-ph
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The categories of this paper are: funct-an