MIMO best practices

[CNIDude]

Hi all,

You will have to excuse me but I am very new to LabVIEW and I have 3 basic questions:

1.) I am experimenting in the lab with the 2x2 MIMO set up by performing some basic testing on your pre-built 2x2AlamoutiQAM with BER software that I downloaded from your site. I'm curious what a typical BER should be with this set up, I am using two USRP2's and two 29XX's(just noticed each one has unique firmware installed, all are rev4) and a distance of only about 2 meters. After a considerable amount of tweaking of the system settings, I have been able to get a relatively consistent BER of around 6% (0.06xx) but also with occasional jumps to ~45% and regular trigger misses (where the BER=1). I would expect to get better BER/link performance with the TX and RX located at short ranges in the lab. Is this the best that I can expect, or am I doing something wrong? 

2.) I am interested in replacing the Alamouti encoder with a convolutional Viterbi encoder and implementing a trellis/sphere decoder into the system RX. I would like to use the platform that has already been created and implement some m. file codes that I created in MATLAB (can I say that word in here? ;), but I cant seem to make any changes or even save my input settings with the pre-built software. Do I have to completely re-invent the wheel or is there any way to make modifications to the downloaded software program?

3.) Is there a simple way to convert MATLAB m. code into the LabVIEW environment? I have heard that there is a way to implement an .m file directly. Is this true?

Thanks for your help!

-J 

[vvkakade]

This link may be helpful to you.

http://www.ni.com/white-paper/4854/en/