Reducing Simulation Effort for RIS Optimization using an Efficient Far-Field Approximation

TL;DR

This paper introduces a fast far-field approximation method that reduces the simulation effort in RIS optimization by extrapolating scatter matrices from a single simulation, maintaining high accuracy for practical use.

Contribution

A novel far-field approximation technique that significantly decreases simulation time for RIS optimization without sacrificing accuracy.

Findings

The method accurately extrapolates scatter matrices from one simulation.

Optimized capacitance values closely match those from full simulations.

Empirical measurements validate the approximation's effectiveness.

Abstract

Optimization of Reconfigurable Intelligent Surfaces (RIS) via a previously introduced method is effective, but time-consuming, because multiport impedance or scatter matrices are required for each transmitter and receiver position, which generally must be obtained through full-wave simulation. Herein, a simple and efficient far-field approximation is introduced, to extrapolate scatter matrices for arbitrary receiver and transmitter positions from only a single simulation while still maintaining high accuracy suitable for optimization purposes. This is demonstrated through comparisons of the optimized capacitance values and further supported by empirical measurements.