# A Novel Radar Cross-Section Calculation Method Based on the Combination of the Spectral Element Method and the Integral Method

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## Abstract

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## 1. Introduction

## 2. Methods

#### 2.1. SEM

#### 2.2. Scattered Fields’ Integral Equations

**r**in space, respectively. In accordance with the superposition principle, the scattered field at any location

**r**can be derived by convolving the equivalent source with its Green function:

#### 2.3. Green’s Function

#### 2.4. RCS Calculation Method

## 3. Experiment

#### 3.1. The Scattered Field Based on the SEM

#### 3.2. The Scattered Field Based on the Integral Method

#### 3.3. Validation of RCS Calculation in Free Space

## 4. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 2.**The model for case 1: (

**a**) the model for SEM based on the scattered field’s governing equation; (

**b**) the model for SEM based on the total field’s governing equation.

**Figure 3.**The comparison of the scattered fields inside the scatterer for two different SEM methods and COMSOL. (

**a**,

**b**) Real and imaginary parts of the x-component electric fields, respectively. (

**c**,

**d**) Real and imaginary parts of the y-component electric fields, respectively. (

**e**,

**f**) Real and imaginary parts of the z-component magnetic fields, respectively.

**Figure 4.**The model for case 2: (

**a**) the model for COMSOL; (

**b**) the model for the proposed method where the source is outside the computational domain.

**Figure 5.**The comparison of the total field strength inside the scatterer for SEM and COMSOL: (

**a**) the comparison of the electric field strength; (

**b**) the comparison of the magnetic field strength.

**Figure 6.**The comparison of the scattered field strength at observation points external to the scatterer for SEM and COMSOL: (

**a**) the comparison of the electric field strength; (

**b**) the comparison of the magnetic field strength.

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**MDPI and ACS Style**

Zhao, H.; Chen, J.; Zhuang, M.; Yang, X.; Zhuo, J.
A Novel Radar Cross-Section Calculation Method Based on the Combination of the Spectral Element Method and the Integral Method. *Symmetry* **2024**, *16*, 542.
https://doi.org/10.3390/sym16050542

**AMA Style**

Zhao H, Chen J, Zhuang M, Yang X, Zhuo J.
A Novel Radar Cross-Section Calculation Method Based on the Combination of the Spectral Element Method and the Integral Method. *Symmetry*. 2024; 16(5):542.
https://doi.org/10.3390/sym16050542

**Chicago/Turabian Style**

Zhao, Hongyu, Jingying Chen, Mingwei Zhuang, Xiaofan Yang, and Jianliang Zhuo.
2024. "A Novel Radar Cross-Section Calculation Method Based on the Combination of the Spectral Element Method and the Integral Method" *Symmetry* 16, no. 5: 542.
https://doi.org/10.3390/sym16050542