becklabash/rectangular-patch-antenna-freq-response

Rectangular Patch Antenna Frequency Response Dataset

Simulated S₁₁ frequency response curves for coaxial-fed rectangular patch antennas with varying dimensions and feed positions.

This dataset was released as part of LaBash et al., "Improving Generative Inverse Design of Rectangular Patch Antennas with Test Time Optimization".

Dataset Description

Coaxial-fed rectangular patch antennas consist of a feed pin that passes through the ground plane to a metallic patch on a dielectric substrate. The design configuration of a single coaxial-fed rectangular patch antenna is parametrized by (L, W, p), where:

• L is the length of the patch in mm
• W is the width of the patch in mm
• p is the position of the feed point relative to the center of the patch along the length axis

Figure 1: Configuration of a Rectangular Patch Antenna fed via coaxial line through the ground plane.

Design Parameter Ranges

• L = [7.5, 52.5] mm (patch length)
• W/L ratio = [0.8, 2] (width to length ratio)
• p = [-6, 0) mm (feed position), enforcing p = (-L/2, 0)

The designs were sampled at higher density at small L and with p close to the edge of the patch, then augmented using an algorithm designed to sample additional triplets (L, W, p) inside the convex hull of the existing dataset while enforcing uniformity.

Simulation Details

The simulations were performed using openEMS, an open-source electromagnetic field solver based on the Finite-Difference Time Domain (FDTD) method. Fixed substrate parameters were used:

• Dielectric constant εᵣ = 3.68
• Substrate thickness = 1.61 mm (aligned with OSH Park's 4-layer prototype service)

To calculate S₁₁ frequency response curves, each antenna was excited with a Gaussian pulse centered at f₀ = 5.5 GHz with a cutoff frequency fₖ = 4.5 GHz to cover the frequency range of interest, f∈[1GHz, 10GHz].

From the port data extracted through simulation, the complex amplitudes of the incident and reflected fields were obtained at N = 1000 regularly spaced frequencies. The reflection coefficient (S₁₁) was computed as the ratio of the reflected wave (u_ref) to the incident wave (u_inc), converted to decibels:

$$\mathrm{\mid }{S}_{11}{\mathrm{\mid }}_{\text{dB}}(f_i)=20{\log }_{10}\left(\mid \frac{u_{\text{ref}}(f_i)}{u_{\text{inc}}(f_i)}\mid \right),i=1,\dots ,N|S\_\{11\}|\_\backslash text\{dB\}(f\_i)\; =\; 20\backslash log\_\{10\}\backslash left(\backslash left|\backslash frac\{u\_\{\backslash text\{ref\}\}(f\_i)\}\{u\_\{\backslash text\{inc\}\}(f\_i)\}\backslash right|\backslash right),\backslash quad\; i=1,\backslash dots,N$$

Figure 2: Example S11 vs. Frequency plot

Dataset Structure

Each sample in the dataset contains:

• Design Parameters:

  • length: Patch antenna length in mm
  • width: Patch antenna width in mm
  • feed_y: Feed point position in mm relative to the center of the patch, along the length axis

• Frequency Response:

  • frequencies: Array of 1000 frequency points per sample (Hz), ranging from 1 GHz to 10 GHz
  • s11: Array of 1000 S11 values (dB) corresponding to each frequency point

• Metadata:

  • id: Unique identifier for each sample

Citation

If you use this dataset in your research, please cite:

@misc{labash2025improvinggenerativeinversedesign,
      title={Improving Generative Inverse Design of Rectangular Patch Antennas with Test Time Optimization}, 
      author={Beck LaBash and Shahriar Khushrushahi and Fabian Ruehle},
      year={2025},
      eprint={2505.18188},
      archivePrefix={arXiv},
      primaryClass={eess.SP},
      url={https://arxiv.org/abs/2505.18188}, 
}