# A Compact Octa-Band Frequency Reconfigurable Antenna for Wireless Applications

^{1}

^{2}

^{3}

^{*}

## Abstract

**:**

## 1. Introduction

- The proposed antenna has a compact size when compared with designs reported in the literature.
- The antenna geometry comprises a simple structure, which minimizes the fabrication losses.
- By utilizing only two diodes, the antenna resonates at eight different frequencies having four different dual modes.

## 2. Antenna Structure and Design Methodology

#### 2.1. Antenna Structure

#### 2.2. Antenna Design Methodology

^{8}ms

^{−1}, ${f}_{p}$ is the central resonating frequency, which is given by:

^{2}, which is 44% smaller compared to the conventional monopole antenna that has an area of 572 mm

^{2}.

## 3. Results and Discussion

#### 3.1. Simulated and Measurement Setup

#### 3.2. Reflection Coefficient

#### 3.3. Far-Field Analysis

#### 3.4. Comparison with State-of-the-Art Work

## 4. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

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**Figure 3.**The simulated reflection coefficient of three different prototypes for the proposed antenna design.

**Figure 6.**The comparison between measured and simulated reflection coefficient for various switching cases; (

**a**) Case-00, Case-01 (

**b**) Case-10, Case-11.

**Figure 7.**Simulated and measured radiation pattern (

**a**) case-00 (

**b**) case-00 (

**c**) case-01 (

**d**) case-10 (

**e**) case-11 (

**f**) case-11.

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**MDPI and ACS Style**

Ghaffar, A.; Awan, W.A.; Hussain, N.; Li, X.-J.
A Compact Octa-Band Frequency Reconfigurable Antenna for Wireless Applications. *Mathematics* **2021**, *9*, 1557.
https://doi.org/10.3390/math9131557

**AMA Style**

Ghaffar A, Awan WA, Hussain N, Li X-J.
A Compact Octa-Band Frequency Reconfigurable Antenna for Wireless Applications. *Mathematics*. 2021; 9(13):1557.
https://doi.org/10.3390/math9131557

**Chicago/Turabian Style**

Ghaffar, Adnan, Wahaj Abbas Awan, Niamat Hussain, and Xue-Jun Li.
2021. "A Compact Octa-Band Frequency Reconfigurable Antenna for Wireless Applications" *Mathematics* 9, no. 13: 1557.
https://doi.org/10.3390/math9131557