# Dual-Band Single-Layer Fractal Frequency Selective Surface for 5G Applications

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## Abstract

**:**

## 1. Introduction

## 2. Self-Similar Structures and Fractal Antennas

## 3. The Unit Cell

- $dx$ is the distance from the center of the metal strip and the corners of Sierpiński triangles to the side;
- $dy$ is the distance in between the bottom and the top of two neighboring Sierpiński triangles.

## 4. Design Parameters and Guidelines

#### 4.1. Simulating in CST Microwave Studio

#### 4.2. Unit Cell Size w and Central Element Width t

#### 4.3. Distance between Bow Ties dx and dy

## 5. Angle of Incidence

## 6. Measurements

## 7. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 1.**Different stages for the Sierpiński triangle [18].

**Figure 6.**E-field comparison. (

**a**) Electric field distribution at 800 MHz. (

**b**) Electric field distribution at $3.5$ GHz.

**Figure 8.**The effects of w [mm] and t [mm]. (

**a**) Frequency shift around 800 MHz. (

**b**) Frequency shift around $3.5$ GHz. (

**c**) Bandwidth shift around 800 MHz. (

**d**) Bandwidth shift around $3.5$ GHz.

**Figure 12.**Measurement setup inside the anechoic chamber for FSS characterization. (

**a**) Side view. (

**b**) Top view.

Parameter | Explanation | Value (mm) |
---|---|---|

w | height of the bow tie | 87 |

t | width of the central element | $0.5$ |

$dx$ | horizontal distance between elements | 3 |

$dy$ | vertical distance between elements | 2 |

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**MDPI and ACS Style**

Decoster, B.; Maes, S.; Cuiñas, I.; García Sánchez, M.; Caldeirinha, R.; Verhaevert, J.
Dual-Band Single-Layer Fractal Frequency Selective Surface for 5G Applications. *Electronics* **2021**, *10*, 2880.
https://doi.org/10.3390/electronics10222880

**AMA Style**

Decoster B, Maes S, Cuiñas I, García Sánchez M, Caldeirinha R, Verhaevert J.
Dual-Band Single-Layer Fractal Frequency Selective Surface for 5G Applications. *Electronics*. 2021; 10(22):2880.
https://doi.org/10.3390/electronics10222880

**Chicago/Turabian Style**

Decoster, Bram, Stephanie Maes, Iñigo Cuiñas, Manuel García Sánchez, Rafael Caldeirinha, and Jo Verhaevert.
2021. "Dual-Band Single-Layer Fractal Frequency Selective Surface for 5G Applications" *Electronics* 10, no. 22: 2880.
https://doi.org/10.3390/electronics10222880