Curated, simulation-first antenna library focused on space and defense sectors. Completed: dipole, microstrip patch. In progress: horn-fed offset parabolic reflector, conformal patch on cylinder, and a 4-element CRPA array. Each design includes HFSS models, parametric sweeps, S11 and 3D pattern plots, benchmarked against typical vendor data-sheet figures.
- Dipole Antenna — ✅ done
- Patch Antenna — ✅ done
- Horn-fed Offset Parabolic Reflector — ⏳ planned
- Conformal Patch on Cylinder — ⏳ planned
- 4-Element CRPA Array — ⏳ planned
The typical starting geometry for antenna designs is the half-wave dipole antenna, so I will start with it, but optimise it to match a commercial half-wave dipole antenna from Southwest Antennas Inc. link.
Following is the geometry and the benchmark specifications:
Starting with the theoretical formulas, I draw the geometry, then assign a lumped port excitation with 50 Ω impedance, create an open region with a PML boundary and an appropriate solution setup centred at 2.35 GHz. Following is the resultant S-parameter:
It is clear that the designed antenna doesn't meet the frequency requirements, so Optimetrics was used to optimise the geometry, and here is an example for the optimisation process where I sweep values for the arm-length multiplier:
I used the S11 metric for determining the bandwidth, and used −10 dB as the limit. This is conservative as it gives 1.925 VSWR, so better than the 2 figure in the benchmark. After optimisation, here are the resultant S11 and VSWR plots:
| Metric | Southwest Antennas #1001-139 (datasheet) | My HFSS Dipole |
|---|---|---|
| Frequency range @ VSWR ≤ 2 : 1 (GHz) | 2.20 – 2.50 | 2.19 – 2.52 |
| Maximum realised gain (dBi) | 2.15 | 2.22 |
| Horizontal AZ beamwidth (°) | 360 | 360 |
| Vertical EL beamwidth (°) | 78 | 79 |
After the dipole, the next canonical single element is the microstrip patch. Here I design a probe-fed 2.4 GHz patch on RO4003C, optimised to the published specs of Cisco’s 6 dBi panel antenna (link). Below are the HFSS geometry and the vendor benchmark sheet:
- First-cut dimensions from closed-form patch formulas (W ≈ 41 mm, L ≈ 31 mm, h = 3.2 mm on RO4003C).
- RG-316 probe feed: inner pin Ø 0.51 mm, PTFE sleeve Ø 1.70 mm.
- Solution setup centred at 2.44 GHz with a PML open region.
Initial VSWR:
Optimetrics sweeps (probe offset & patch length/width) as below were done:
Using VSWR ≤ 2 as the bandwidth criterion, the optimisation process converged to this:
(blue = E-plane, red = H-plane)
| Metric | Cisco AIR-ANT2460P-R (datasheet) | My HFSS Patch |
|---|---|---|
| Frequency range @ VSWR ≤ 2 : 1 (GHz) | 2.400 – 2.484 | 2.399 – 2.485 |
| Maximum realised gain (dBi)* | 6.0 | 7.35 |
| E-Plane 3 dB beam-width (°) | 69 | 76.8 |
| H-Plane 3 dB beam-width (°) | 75 | 79.5 |
* Datasheet includes the 0.9 m AA-9303 pigtail, RP-TNC connector and radome; those add ≈ 1.3 dB loss and broaden the lobes by ≈ +8° (E) / +4° (H).