Re: [Discuss-gnuradio] MIMO-OFDM 2x1 Alamouti code.

[Tom Rondeau]

On Mon, Jan 3, 2011 at 11:50 PM,  <address@hidden> wrote:
> Hi all,
>
> Maybe this question has already been done, but I didn't found any relevant
> information about it. I want to implement a MIMO OFDM system (2X1) with
> the Alamouti's code in the URSP one, but so far I've only been able to run
> an OFDM system using the benchmark_ofdm_tx.py and benchmark_ofdm_rx.py
> codes.
>
> The system that I'll implement consist in two RFX2200 cards in the same
> USRP working as the transmitter and one RFX2200 in another USRP working as
> a receiver.
>
> I really don´t know how I can connect the two RFX2200 cards in the first
> USRP one to sincronize them, because I tried to implement the alamouti
> code and I need both of them transmitting at the same time, then in the
> receiver use the Alamouti decoding to obtain the information sent. I once
> read that it had to connect both RFX2200 card with a wired link in order
> to sincronize them, is this correct or how I can sincronize them, or if
> need a cable how I can make the connection with the RFX2200 cards ?
>
> I want to ask too if there are any MIMO-OFDM implementation in GNURadio, I
> was checking and I didn't found any related to this.
>
> I hope someone can help or guide me with my doubts, any link, information
> or answer will be helpful.
>
> Thks in advance.


Matt Ettus and I did some preliminary work on getting Alamouti codes
into GNU Radio a while back. We've never found the time to complete
it, but you can find it by setting up a remote tracking branch to
http://gnuradio.org/git/trondeau.git and checkout the branch ofdm.

It's in various stages of working, so no guarantees, but it will at
least show you how we did the synchronization.

Tom