Reply by nammi sairamesh May 22, 20072007-05-22
Hi,
I do agree with your resul if the channel model is
flat fading . If you use a frequency selective fading
channel (eg. i.i.d or exponential ), we can not assume
the performance is equal to that of MIMO flat fading
without OFDM.
Best Regards,
-SaiRamesh

--- Nandan Das wrote:

> I would start with the 2x2 MIMO (single carrier)
> before I move to OFDM. For
> the flat-fading channel model, there are numerous
> standard results for different receivers, e.g. MMSE,
> MMSE-SIC, MMSE-OSIC (
> e.g. see either David Tse's book or Paulraj's book).
>
> Now, if you go to OFDM for the same channel model,
> you should see the exact
> same performance.
>
> I have done that and verified that I indeed do get
> the same performance.
>
> thanks
> Nandan
>
> On 5/19/07, nammi sairamesh
> wrote:
> >
> > Hi,
> > We are also working on the same subject. We
> are
> > unable to verify any standard plot in this
> subject.
> > What kind of detector u are using for MIMO
> detection.
> > I assume the performance depends on the detector u
> are
> > using.
> > Best Regards,
> > -SaiRamesh.
> >
> >
> > --- l...@hotmail.com wrote:
> >
> > > Hello everyone.
> > >
> > > I'm building a MIMO-OFDM simulator.
> > > Can I have some discussion with anyone
> interested in
> > > this,please?
> > >
> > > For example, I'm buildiing a 4-by-4 MIMO-OFDM
> > > simulator.
> > > Then, what is the best way I can verify the BER
> of
> > > my MIMO-OFDM simulator?
> > >
> > >
> > > Since I use 64-PSK, I assumed that, if I adopt a
> > > Gaussian channel for MIMO-OFDM with 64-PSK, then
> the
> > > BER will be the same as 64-PSK in AWGN.
> > > But, the result is not like that.
> > > Sometimes, MIMO-OFDM with 64-PSK in a Gaussian
> > > channel performs better than a 64-PSK Gaussian
> > > channel performance.
> > >
> > > Can anyone point out what can be the problem of
> my
> > > coding?
> > > Isn't it no system can perform 64-PSK in AWGN?
> > >
> > > Thank you so much.
> > >
> >
> >
> >
Reply by Nandan Das May 22, 20072007-05-22
I would start with the 2x2 MIMO (single carrier) before I move to OFDM. For
the flat-fading channel model, there are numerous
standard results for different receivers, e.g. MMSE, MMSE-SIC, MMSE-OSIC (
e.g. see either David Tse's book or Paulraj's book).

Now, if you go to OFDM for the same channel model, you should see the exact
same performance.

I have done that and verified that I indeed do get the same performance.

thanks
Nandan

On 5/19/07, nammi sairamesh wrote:
>
> Hi,
> We are also working on the same subject. We are
> unable to verify any standard plot in this subject.
> What kind of detector u are using for MIMO detection.
> I assume the performance depends on the detector u are
> using.
> Best Regards,
> -SaiRamesh.
> --- l...@hotmail.com wrote:
>
> > Hello everyone.
> >
> > I'm building a MIMO-OFDM simulator.
> > Can I have some discussion with anyone interested in
> > this,please?
> >
> > For example, I'm buildiing a 4-by-4 MIMO-OFDM
> > simulator.
> > Then, what is the best way I can verify the BER of
> > my MIMO-OFDM simulator?
> >
> >
> > Since I use 64-PSK, I assumed that, if I adopt a
> > Gaussian channel for MIMO-OFDM with 64-PSK, then the
> > BER will be the same as 64-PSK in AWGN.
> > But, the result is not like that.
> > Sometimes, MIMO-OFDM with 64-PSK in a Gaussian
> > channel performs better than a 64-PSK Gaussian
> > channel performance.
> >
> > Can anyone point out what can be the problem of my
> > coding?
> > Isn't it no system can perform 64-PSK in AWGN?
> >
> > Thank you so much.
> >
Reply by nammi sairamesh May 21, 20072007-05-21
Hi,
We are also working on the same subject. We are
unable to verify any standard plot in this subject.
What kind of detector u are using for MIMO detection.
I assume the performance depends on the detector u are
using.
Best Regards,
-SaiRamesh.
--- l...@hotmail.com wrote:

> Hello everyone.
>
> I'm building a MIMO-OFDM simulator.
> Can I have some discussion with anyone interested in
> this,please?
>
> For example, I'm buildiing a 4-by-4 MIMO-OFDM
> simulator.
> Then, what is the best way I can verify the BER of
> my MIMO-OFDM simulator?
> Since I use 64-PSK, I assumed that, if I adopt a
> Gaussian channel for MIMO-OFDM with 64-PSK, then the
> BER will be the same as 64-PSK in AWGN.
> But, the result is not like that.
> Sometimes, MIMO-OFDM with 64-PSK in a Gaussian
> channel performs better than a 64-PSK Gaussian
> channel performance.
>
> Can anyone point out what can be the problem of my
> coding?
> Isn't it no system can perform 64-PSK in AWGN?
>
> Thank you so much.
>
Reply by lsw0...@hotmail.com May 18, 20072007-05-18
Hello everyone.

I'm building a MIMO-OFDM simulator.
Can I have some discussion with anyone interested in this,please?

For example, I'm buildiing a 4-by-4 MIMO-OFDM simulator.
Then, what is the best way I can verify the BER of my MIMO-OFDM simulator?
Since I use 64-PSK, I assumed that, if I adopt a Gaussian channel for MIMO-OFDM with 64-PSK, then the BER will be the same as 64-PSK in AWGN.
But, the result is not like that.
Sometimes, MIMO-OFDM with 64-PSK in a Gaussian channel performs better than a 64-PSK Gaussian channel performance.

Can anyone point out what can be the problem of my coding?
Isn't it no system can perform 64-PSK in AWGN?

Thank you so much.