unit cell and periodic boundary conditions

[shahid78]

in CST MWS we have unit cell boundary condition as well as periodic boundary condition
i am just wondering whats the difference between the two ?

and which one we should use for EBGs and which one for array simulation and also whether these 2 boundary conditions work with both transient as well frequency domain solver?


any comments are welcome


regards

 

[prafuldeo]

hello shahid..
in unit cell boundary condition one can have an oblique incident. for EBG we use periodic conditions to simulate infinite periodic array. unit cell works with frequency solver... hope it helps

 

[shahid78]

hi prafuldeo

well thanks for your comments but i still dont understand

you said we use periodic boundary conditions for EBG but why not unit cell ? when we use unit cell , it also means our structure is periodic


if you post any simulated model in cst using unit cell boudary condition. that would be great
because i dont know how to excite the structure when using unit cell boundary condtion ? which port to use , waveguide port or plane wave!!

i also dont understand how to interpret the results of unit cell boundary condition

any comments would be great help

regards

 

[prafuldeo]

hi..
there is good example given in CST online help regarding unit cell simulation. Have a look.i m sure you will find it useful.