How to use antenna toolbox with a measured antenna ?

Hello !

I am trying to plot an antenna pattern from in situ real measurements of an antenna. My measurements comprise X, Y Z in m and the measured attenuation in dB.

After conversion into azimuth and elevation, unfortunately, this does not seem compatible with either measuredAntenna or patterncustom.

With patterncustom I get the following error :

Error filling holes for shared_channel:patternCustom:RepeatedPoints.

Floating point numbers are not allowed as holes. They should be

converted to character vectors.

With measured antenna, MagE I do not have, as I only have the measured attenuation...

Anyway to get my antenna plots (3D and sections) from my measurements ?

Thanks in advance,

Kindly,

[Ganapathi Subramanian R]

What do you mean by attentuation here and do you have any other data related to directivity?

[Félix]

Thank your for your help !

I do not have any directivity data, we cover a semi sphere around our measured antenna. At each sample point, we measure the signal intensity loss, in dB, which I refer to as attenuation.

Typically looks like this :

X(m) Y(m) Z(m) Attenuation(dB)

-2,488942666 6,88120177 21,05000067 -36.5

-2,06476295 7,036021853 21,19000068 -28.1

Thanks !

[Ganapathi Subramanian R]

Hi Felix,

According to recent MATLAB documentation, the 'patternCustom' function requires antenna directivity, E-fields, H-fields, or power of an antenna or array as input for 'magE' parameter . I suggest you to transform the attentuation data into directivity by finding a correlation between the observed attentuation and directivity.

For further information regarding 'patternCustom' function, please refer to the below documentation.

https://www.mathworks.com/help/antenna/ref/patterncustom.html

[Félix]

thannks, it is what i had gathered as well...

Answer 1

[Pooja Kumari]

Hi Felix,

I unserstand you are trying to plot an antenna pattern from in situ real measurements of an antenna. You are facing "Error filling holes for shared_channel:patternCustom:RepeatedPoints.Floating point numbers are not allowed as holes. They should be converted to character vectors." error using Pattern Custom function.

If you have attenuation in dB (Attenuation), you can convert it to a relative magnitude scale by assuming that the attenuation is relative to the maximum signal strength you measured or a known reference.

I think the error will be resolved when the parameters are passed in the correct order as follows:

patternCustom(magE, theta, phi);

For more information on Pattern Custom function, you can refer to the below documentation:

https://www.mathworks.com/help/antenna/ref/patterncustom.html

[Félix]

I have tried that as well, unsuccesfully. I will try to measure something else than attenuation, thanks for your help