Substrate dielectric: 3.5

Substrate height : 1.5mm

Frequency: 2.5GHz

I followed a particular video on YouTube to guide me, and used an online calculator for the width and length of patch, inset feed length and width. The following are the dimensions used:

length of patch: 31mm

width of patch: 40mm

gap in patch was about 3.4 wide

inset feed point: 12 mm

width of conductor was about 4.5mm [impedance at the edge was about 202.5 ohms and my conductor's is 50 ohm]

I ran an optimetrics sweep and the best gain I have been able to get is about 8.5dB. Is this practical? I feel i should be getting more. I have seen certain simulations for similar frequencies in HFSS and some get around 20dB. Am I doing something wrong? Image to my S11 is belowoptimetrics sweep accross certain inset feed lengths and the best I got accross 8 mm to 11mm in steps of 0.5


What is the application for which the design is carried out? For a single element patch antenna system, a farfield gain of 5 to 7 dB is usually common. 8.5 dB gain is possible and is good. You are achieving a return loss of nearly about 10 dB (or, -10 dB as shown in most simulation environments). More improvement on return loss will be better and the same can be achieved by tuning the dimensions of the radiating patch. This however, depends on the application for which the design is carried out. The requirements of the application largely determine the design. From your design, good gain is achieved but return loss is not that good. Something around 15 dB will be better for any application. The designed antenna also exhibits multi-band operation as can be seen from the return loss plot.

  • \$\begingroup\$ Thanks for your contribution. I have been able to change the feed length to achieve some appreciable -20dB in my S11 graph; imgur.com/cR8c8mW but my frequency is resonating around 2.6GHz instead of 2.5. How do I enable it to resonate at 2.5? I was thinking I alter the length of patch but won’t that ruin the impedance match I have attained? \$\endgroup\$ – Kwaku E. Biney Jun 29 '20 at 5:53
  • \$\begingroup\$ Seeing your new image, I can say that the return loss is around -5 dB for 2.5 GHz. You can make the resonant frequency jump to 2.5 GHz by fine tuning the inset feed length or the gap and also ground dimensions (maintain it as a square ground). \$\endgroup\$ – Kaswechiha Jun 29 '20 at 6:05

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