Multiple Beam Digital Beamforming

Hello,

I am working on my senior design project and was hoping I could find
some help. I need to design a MATLAB program which generates multiple
beams for a 4x4 planar antenna array. Right now, I am assuming that I
know the direction of the incoming signals (theta and phi). I have some
source code which generates the beam for one incoming signal. I am not
quite sure how I can extend the code to handle multiple beams.

If anyone can provide any tips or source code that I could look at, I
would greatly appreciate it. If I need to provide more information,
please let me know. Thanks.

<chimera451@gmail.com> wrote in message 
news:1141665552.481797.250650@u72g2000cwu.googlegroups.com...
> Hello,
>
> I am working on my senior design project and was hoping I could find
> some help. I need to design a MATLAB program which generates multiple
> beams for a 4x4 planar antenna array. Right now, I am assuming that I
> know the direction of the incoming signals (theta and phi). I have some
> source code which generates the beam for one incoming signal. I am not
> quite sure how I can extend the code to handle multiple beams.
>
<...>
You could just repeat it.  If you've got no significant non-linearities then 
repeating the whole thing for each beam, ensuring that you use the same 
element locations and patterns, is simple.

best of luck - Mike

chimera451@gmail.com wrote:


> I am working on my senior design project and was hoping I could find
> some help. I need to design a MATLAB program which generates multiple
> beams for a 4x4 planar antenna array. Right now, I am assuming that I
> know the direction of the incoming signals (theta and phi). I have some
> source code which generates the beam for one incoming signal. I am not
> quite sure how I can extend the code to handle multiple beams.
> 
> If anyone can provide any tips or source code that I could look at, I
> would greatly appreciate it. If I need to provide more information,
> please let me know. Thanks.
> 

Basically a beamformer is nothing more than a variable delay for each 
receive channel, followed by a summing node. That is how medical 
ultrasound scanners work and there should be plenty of literature. If 
multiple directions are to be received at the same time you tap off from 
the delay lines (or algorithm) at the correct spot, where your signals 
would be in phase for the selected direction.

In ultrasound there is also 'dynamic focus' where the taps are adjusted 
with time-of-flight but I guess you don't have to focus really close in 
this case.

BTW, Skolnik's "Radar Handbook" is an excellent resource here.

Regards, Joerg

http://www.analogconsultants.com

chimera451@gmail.com wrote:
> Hello,
>
> I am working on my senior design project and was hoping I could find
> some help. I need to design a MATLAB program which generates multiple
> beams for a 4x4 planar antenna array. Right now, I am assuming that I
> know the direction of the incoming signals (theta and phi). I have some
> source code which generates the beam for one incoming signal. I am not
> quite sure how I can extend the code to handle multiple beams.
>
> If anyone can provide any tips or source code that I could look at, I
> would greatly appreciate it. If I need to provide more information,
> please let me know. Thanks.

I think the beamformer basically uses the single-beam ealgorithm and
scans theta and phi. It's quite expensive, computationally speaking.

Rune

thanks for the posts...it definitely helps...i have found some
information that should help me...i will let you guys know how things
turn out.