2D FDTD with plane wave incidence(code in matlab)

[rrumpf]

code fdtd 2d matlab

I see your point and perhaps you are right. I am so used to normalizing everything because it is good numerical practice, that I do it almost without thinking about it anymore. I would think if you proceed without normalizing, be VERY sure to check that your coefficients are scaling the terms correctly. You could easily modify your algorithm in some strange way, and if you haven't normalized, problems could suddenly arise from a code that worked previously.

-Tip

 

[woogung]

2-d finite difference code matlab

thanks iyami and rrumpf, i got a lot

 

[bdm_praveen]

plane wave source fdtd

hi i am doing project on fdtd topic
i need some help ...
how can i find s parameters for one antenna using fdtd(matlab) method..
plz help me.....
thank you..
my email id is bdmpra@yahoo.co.in

 

[xephyrind]

fdtd oblique incidence

I have a question... I just learned FDTD recently and I am wondering about running a wave using FDTD. Let's say the incident wave I want to propagate is:

a_x is unit vector pointing in x direction. c= speed of the wave.

E = E_x = a_x*sin(x-c*t) , 0<x-ct<8

If I just plug in the value of my wave into the designated region into my grid at t = 0, then let the FDTD run, I get the feeling that my wave will not propagate in x direction. It seems to be emanating in all directions. Is my feeling correct?

 

[sundariit]

Thanks a lot for 2D FDTD code

 

[sannxi]

Re: 2d fdtd matlab

attached with this message is a 2D FDTD(TE mode) with a plane wave source

i borrowed the 2d fdtd by susan hagness and changed the source to plane wave...

please feel free to comment if there is any error;-)

Thank you for you shared code, i want to calculate reflectivity and transmissivity,pls explain to me how to take.:|

 

[sannxi]

Re: fdtd with plane wave source matlab

Hi, Do you know how to calculate reflectivity and transmissivity using FDTD?
if you do ,pls explain to me.
Thanks a lot.

 

[k91812122]

Thanks very much. I have waited for a long time to active my account.

 

[otamusic]

Hi,
May I ask you guys a question about the index of filed correction in this matlab code?

Line 455~456:
ex(is1:is2-1,js1)=ex(is1:is2-1,js1)-((dt/(epsz*dx)).*hz_inc(is1:is2-1));
ex(is1:is2-1,js2)=ex(is1:is2-1,js2)+((dt/(epsz*dx)).*hz_inc(is1:is2-1));

->why is not ex(is1:is2 ...

Line 575:
hz(is1-1,js1:js2-1)=hz(is1-1,js1:js2-1)+(dt/(muz*dx)).*ey_inc(is1);

->why is not hz(is1,....

Thanks a lot!!

 

[iyami]

Hi,
May I ask you guys a question about the index of filed correction in this matlab code?

Line 455~456:
ex(is1:is2-1,js1)=ex(is1:is2-1,js1)-((dt/(epsz*dx)).*hz_inc(is1:is2-1));
ex(is1:is2-1,js2)=ex(is1:is2-1,js2)+((dt/(epsz*dx)).*hz_inc(is1:is2-1));

->why is not ex(is1:is2 ...

Line 575:
hz(is1-1,js1:js2-1)=hz(is1-1,js1:js2-1)+(dt/(muz*dx)).*ey_inc(is1);

->why is not hz(is1,....

Thanks a lot!!

I am not sure where your code is from and what is1 and is2 represent but look at the boundaries of your model.
The lowest index for H and E does not necessarily coincide since they are located at different postions (different
distances from the boundary).

Have a look at the FDTD guide (and the corresponding wiki) from the thread

https://www.edaboard.com/threads/139831/


Look at the structure of the Yee cells.