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2021-03-17

The New Localized Ray-Tracing-Maximum-Likelihood Method Estimates the Probability Distribution of the Field Strength

By Mehdi Ardavan
Progress In Electromagnetics Research C, Vol. 111, 47-59, 2021
doi:10.2528/PIERC21021308

Abstract

The Ricean probability density function (pdf) is widely used to estimate the electromagnetic field distribution in indoor environments. The goal of using the Ricean or other pdfs is to evade the computational cost of deterministic field calculation. The parameters of the pdfs are usually obtained using the maximum-likelihood estimation which is here shown to fail in local areas close to the antenna where the direct field varies significantly. This paper presents the new localized maximum likelihood method which is valid in close regions as well. Moreover, the maximum-likelihood method requires a large number of field values within the local area to yield the parameters of the pdf. This paper presents the ray-tracing maximum-likelihood (RTML) method where a much lower number of field values are required. These values are determined using ray-tracing and without the need to account for the computationally expensive higher-order reflections. The RTML fails in local areas close to the antenna, and thus the new localized RTML is presented to restore accuracy.

Citation


Mehdi Ardavan, "The New Localized Ray-Tracing-Maximum-Likelihood Method Estimates the Probability Distribution of the Field Strength," Progress In Electromagnetics Research C, Vol. 111, 47-59, 2021.
doi:10.2528/PIERC21021308
http://www.jpier.org/PIERC/pier.php?paper=21021308

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