How can I know my desired signal for LMS algorithm?

Hi,

   I've got a problem with the implementation of LMS algorithm. I'm
looking for desing a Digital beamforming antenna for my final
project.Someone told me that it's better if I use LMS algorithm to
calculate the weights of the array elements because I don't know how many
users there are and those users are mobile users. 

   My problem is that LMS algorithm needs to know the desired signal...I'm
working with a WiMax Mobile System, an SOFDMA system of 5ms frames. I don't
have time to transmit and received a training sequence since I need to
calcute everything in real time and I don't have an spreading code as in
the case of a CDMA system. How should I calculate the error without a
reference signal?? What shoudl I use as initial value of complex weights?

Thanks for your help. I REALLY NEED IT

On Nov 12, 2:55 am, "scc" <sandracorr...@gmail.com> wrote:
> Hi,
>
>    I've got a problem with the implementation of LMS algorithm. I'm
> looking for desing a Digital beamforming antenna for my final
> project.Someone told me that it's better if I use LMS algorithm to
> calculate the weights of the array elements because I don't know how many
> users there are and those users are mobile users.
>
>    My problem is that LMS algorithm needs to know the desired signal...I'm
> working with a WiMax Mobile System, an SOFDMA system of 5ms frames. I don't
> have time to transmit and received a training sequence since I need to
> calcute everything in real time and I don't have an spreading code as in
> the case of a CDMA system. How should I calculate the error without a
> reference signal?? What shoudl I use as initial value of complex weights?
>
> Thanks for your help. I REALLY NEED IT

Some of the techniques used for blind equalization might be useful. Is
there a constant modulus for your signal-of-interest that you might
exploit in your algorithm? If so, you may not need a training
sequence.

Darol Klawetter

On Nov 12, 2:55 am, "scc" <sandracorr...@gmail.com> wrote:
> Hi,
>
>    I've got a problem with the implementation of LMS algorithm. I'm
> looking for desing a Digital beamforming antenna for my final
> project.Someone told me that it's better if I use LMS algorithm to
> calculate the weights of the array elements because I don't know how many
> users there are and those users are mobile users.
>
>    My problem is that LMS algorithm needs to know the desired signal...I'm
> working with a WiMax Mobile System, an SOFDMA system of 5ms frames. I don't
> have time to transmit and received a training sequence since I need to
> calcute everything in real time and I don't have an spreading code as in
> the case of a CDMA system. How should I calculate the error without a
> reference signal?? What shoudl I use as initial value of complex weights?
>
> Thanks for your help. I REALLY NEED IT

There is also a related paper at

http://www.ee.columbia.edu/~dpwe/LabROSA/proceeds/asilomar2003/pdffiles/papers/0507.pdf