PIFA Antenna Design Simulation

Design Overview

The PIFA was designed with the following parameters:

• Resonant Frequency: 5 GHz
• Substrate Material: Duroid (Dielectric constant = 2.2)
• Dimensions: Custom dimensions based on simulation optimization.

Simulation Results

a) Meshed antenna   b) Farfield results of the PIFA antenna

Return loss (S11)

The return loss analysis for the PIFA antenna shows that in both free-space and packaged conditions, the return loss is below -20 dB, indicating acceptable antenna performance. Specifically, the return loss for the antenna in free space reaches approximately -28 dB at 5 GHz, demonstrating strong impedance matching and efficient operation. For the antenna packaged within a Wi-Fi router, the return loss shifts to around -22 dB at 3.85 GHz, still reflecting good performance but with a shift in resonant frequency. This difference highlights the impact of the packaging environment, which can alter the antenna’s impedance characteristics and resonant behavior, underscoring the need to account for these factors in practical antenna design to ensure consistent performance.

Farfield results of PIFA antenna the packaged using ABS plastic material

Comparison of return loss for PIFA in free space and Antenna Packaged within a Wi-Fi Router

Radiation Pattern

The designed antenna demonstrates notable performance characteristics. Specifically, the 2D and 3D gain analysis shows that the PIFA antenna in free space exhibits a peak gain of approximately 3.5 dBi at 5 GHz, with a relatively symmetrical radiation pattern that ensures consistent coverage. When the antenna is packaged within a Wi-Fi router, the peak gain shifts to approximately 2 dBi at 3.85 GHz, and the radiation pattern becomes more irregular, indicating the influence of the surrounding environment. This comparison highlights how packaging affects the antenna's directional gain and uniformity, emphasizing the importance of considering environmental impacts in antenna design to maintain optimal performance.

a) 3D total gain plot   b) 2D total gain plot of PIFA Antenna in Free Space

a) 3D total gain plot   b) 2D total gain plot of PIFA Antenna Packaged within a Wi-Fi Router

Gain and Efficiency

The designed antenna demonstrates notable performance characteristics. Specifically, the gain for the unpackaged antenna is approximately 3.5 dBi, with a total efficiency exceeding 99.8%, indicating exceptional power transfer and minimal loss. For the packaged antenna, the gain is approximately 2 dBi, while maintaining a total efficiency of over 99%, showcasing reliable performance with efficient radiation despite the packaging constraints.

Farfield Stacked 2D Total Gain of PIFA Antenna in Free Space, Freq = 5 GHz , Red: Phi = 0 °, Green: 90 °

Farfield Stacked 2D Total Gain of PIFA Antenna Packaged within a Wi-Fi Router, Freq = 3.85 GHz , Red: Phi = 0 °, Green: 90 °

Recommendations and Next Steps

• Impedance Matching: Further fine-tuning may be required for improved matching across a wider bandwidth.
• Integration: Consider the effects of nearby components in a device for practical deployment.
• Prototype Testing: Fabrication and real-world testing to validate simulation results.