is there a software that can iterate the near field to obt

[irfan1]

Hi all..
I am looking for a software that can iterate the near field distribution to obtain the fields at the far zone...Lets say we have the near field distribution over a plane or over a line(in 2D) from a FDTD simulation and we want to iterate these field dsitributions in free space to find the fields in the far zone..is there such software that can do this?

Thanks in advance

 

[Kit-the-great]

Re: is there a software that can iterate the near field to o

You can use the FemL@b 2.3 (Electromagnetics module), but IMHO the more easy way is to write Your own M@tlab code (if You need to evaluate the radiation integral only for limited number of cases (3-D plane and 2-D curve for ex.) it's not a very complex problem), because in any case You must learn the M@tlab to use the FemL@b and after this learning You shouldn't have a problems with this code writing.

Best regards,
Kit-the-great

 

[eirp]

Re: is there a software that can iterate the near field to o

Hi,

I also recommend to write your matlab script as Kit recommends.
Look into some theory of antenna measurement, near to far field transformation can be treated as Fourier transformation which is very simple in Matlab!

Look into attachment how it can be made -

Usually we have defined sources in cartesian coordinates (magnetic currents M and electric currents J) and far field in spherical coordinates is wanted.
Then electric (F) and magnetic (A) vector potential can be calculated by attached equations. From potentials electric or magnetic far field can be easily derived like E_{theta}=-j*omega*A_{theta} ...

Good luck

 

[irfan1]

Re: is there a software that can iterate the near field to o

Thank you very much
Now that I need to calculate the magnetic and electric currents over the boundary

 

[eirp]

Re: is there a software that can iterate the near field to o

Thank you very much
Now that I need to calculate the magnetic and electric currents over the boundary

Electric and magnetic sources are dual..
Let's consider microstrip ptch antenna for example, you can calculate radiation by two ways:

1) from electric currents - you need to integrate J(x,y)=( Jx(x,y),Jy(x,y) ) over the p*a*t*ch surface (J=n x H)

or

2) from magnetic currents (=electric field x normal to the boundary) - you need to integrate vector product (M=n x E) around the boundary.

Now you need to choose which leads to easier implementation..

Rgz,

Eirp

 

[irfan1]

Re: is there a software that can iterate the near field to o

Thank you very much
I ll try to code in matlab... when I am finished I will share it with every one

 

[jjantenna]

Re: is there a software that can iterate the near field to o

How is going about the code?

 

[irfan1]

Re: is there a software that can iterate the near field to o

My problem is 2D... I wrote a code based on the 2D Green's function..but when I calculated the electric current, somehow the matrix including the current elements turned out to be singular.