## 3 Results and Discussion
### Electromagnetic Simulation and Analysis for Dielectric Heating Applications
#### 3.2.1 Frequency Response of Horn Antenna  
The frequency response and performance characteristics of the horn antenna, as shown in Figure 6, highlight its suitability for dielectric heating applications. The 3D radiation pattern with horn antenna structure shown in Figure 6a demonstrates a highly directional radiation pattern, with concentrated electromagnetic energy along the z-axis. This efficient focusing of the electric field ensures effective energy delivery to the target dielectric ma  
\begin{table}
\begin{tabular}{l c c c c} \hline \multirow{2}{*}{**Components of Fish**} & \multicolumn{2}{c}{**Dielectric Constant \(\left({}^{\epsilon}\right)\)**} & \multicolumn{2}{c}{**Dielectric Loss \(\left({}^{\epsilon}\right)\)**} \\ \cline{2-5}  & **Fish** & **Fish After Salt Coating** & **Fish** & **Fish After Salt Coating** \\ \hline Fish scale & 32.77 & 56.87 & 9.59 & 17.64 \\ Fish skin & 32.62 & 34.31 & 10.18 & 15.92 \\ Fish muscle & 25.87 & 40.88 & 14.22 & 16.20 \\ \hline \end{tabular}
\end{table}
Table 2: Dielectric properties of _Cirrhinus microlepis_ tissues at 2.45 GHz.  
terial while minimizing energy losses with a 12 dB antenna gain. The uniformity of the field distribution suggests that the antenna design is optimized for directing electromagnetic waves, making it particularly effective for biological tissue heating at the specific frequency of 2.45 GHz. The S-parameter analysis in Figure 6b further supports the antenna's performance by evaluating its return loss (S11 parameter). The graph identifies three resonant frequencies: 1.88 GHz, 2.45 GHz, and 2.97 GHz. At 2.45 GHz, the return loss reaches a minimum value of \(-34.98\) dB, indicating optimal impedance matching and minimal power reflection. This signifies that the antenna is highly efficient at transmitting electromagnetic energy at 2.45 GHz, the primary frequency for dielectric heating. This behavior follows the reflection coefficient Equation (1), where a lower reflection coefficient (\(\Gamma\)) results in improved energy transmission into the target material. In comparison, the return losses at 1.88 GHz and 2.97 GHz are \(-10\) dB, reflecting acceptable performance but reduced efficiency relative to 2.45 GHz. These variations in power reflection influence the power density (P), as described by Equation (4), which determines how effectively the electromagnetic energy is delivered to the target tissues. The 2D radiation pattern of the horn antenna, depicted in Figure 6c, provides additional insights into its performance. The E-plane exhibits a strong and highly directional main lobe, while the H-plane shows a broader energy distribution. This anisotropic radiation pattern highlights the antenna's ability to concentrate electromagnetic waves in the desired direction, ensuring focused energy delivery to the target. The well-defined main lobe and reduced side lobes minimize energy dispersion and interference, enhancing the overall efficiency of the antenna in dielectric heating applications.  
Since energy absorption is a function of the tissue's dielectric properties and the intensity of the electric field, the power density Equation (4) and SAR Equation (3) provide a quantitative basis for evaluating how the antenna's design impacts energy distribution within the biological tissues. In summary, the frequency response analysis of the horn antenna demonstrates its superior performance at 2.45 GHz, characterized by minimal return loss, a highly directional electric field distribution, and a focused radiation pattern. These attributes make the horn antenna an excellent choice for dielectric heating applications, ensuring efficient energy transfer, uniform heating, and effective performance for biological tissue treatment.