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Port power input and antenna efficiency

Anna Tz. Electronic and Electrical Engineering

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Hello everyone,

I am trying to find the efficiency of a horn antenna I have simulated.

The antenna has a circular port that is excited with TE11 mode and has 1W input power.

However, when I integrate the norm of the poynting vector on the end aperture surface of the antenna, I get a value greater than 1W.

Furthermore, when I integrate the same expression on the surface of the circular port, the value I get is less than 1W.

I am really confused about this.

Can anyone please help me understand what's happening and propose a correct way to calcuate the antenna's efficiency?


1 Reply Last Post 4 juin 2020, 15:13 UTC−4
Dave Greve Certified Consultant

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Posted: 4 years ago 4 juin 2020, 15:13 UTC−4

To get the emitted power, you need to integrate the dot product of the Poynting vector with the surface normal. Don't forget about the difference between average and peak value.

If you specify an incident port power of 1 W, the actual power will be less because of reflection.

If this doesn't help- you will need to post your (solution-less) model.

To get the emitted power, you need to integrate the dot product of the Poynting vector with the surface normal. Don't forget about the difference between average and peak value. If you specify an incident port power of 1 W, the actual power will be less because of reflection. If this doesn't help- you will need to post your (solution-less) model.

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