Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Array of Dipoles:Different results from Matlab and NEC

Status
Not open for further replies.

yvonne82

Newbie level 5
Joined
Jul 16, 2008
Messages
8
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,341
Hi,
I wrote a Matlab program for an array of dipoles in different configurations. Most of the results of farfield pattern match with NEC. The problem is that when I drive 2 dipoles (the rest remain short circuited), the farfield pattern (MATLAB) does not match with NEC. It matches (both is driven with +1V as excitation voltage) with NEC when 1 dipole is +1V and another dipole is -1V (in NEC) (Refer to the attachment). I've check all the sign and couldn't find the errors in my program.

However, for the same configuration, the results from Empire Xccel matches with my MATLAB program.

Any idea why its happening?

Thanks,
 

hi yvonne82
i also have designed dipole antenna using CST mws. but i have a problem with feeding to antenna. I used coaxial cable but it is not balanced. i want to use SMA connector to get balun. Do u know how it is connected to antenna?

thank you
 

Hi,
I'm not sure about design dipole antenna using CST but in Empire, i just use point feed (i.e. lumped port) to feed dipole antenna. It is easier and much quicker to simulate. To balance the coaxial cable, you need to use the balun in order to balance it but i did this in measurement, not in simulation.

Hope it helps,


>i also have designed dipole antenna using CST mws. but i have a problem with >feeding to antenna. I used coaxial cable but it is not balanced. i want to use SMA >connector to get balun. Do u know how it is connected to antenna?
 

Hi Kaandee,
simplest way to use a balun in simulation is to use a quarter wave sleeve on the coax (a copper strip lembda(guided)/4 in length and shorted to outer of coax) to block the ouer shield current due to balanced to unbalanced transition.
 

Hello,

You should check your Matlab code. NEC results probably are Ok.
 

it is normal.
it depents on the numerical methot which you use and you must check impedance matching and mesh size ın your matlab code
 
Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top