Hi all,

I am trying to create a two transmitter setup with two USRP2s connected with the MIMO cable. I use the trunk version of GNURadio (Friday, Jan 29,2010) on laptops running Ubuntu 9.04.

From previous emails and looking at the code, the relevant code for two transmitter setup seems to be the test_mimo_tx file in usrp2/host/apps. I update the firmware of the master USRP2 with mimo_tx.bin as pointed out in http://gnuradio.org/redmine/wiki/gnuradio/USRP2UserFAQ.

sudo ./u2_flash_tool --dev=/dev/sdb -t s/w apps/mimo_tx.bin -w

and for the slave USRP2, I use

sudo ./u2_flash_tool --dev=/dev/sdb -t s/w apps/mimo_tx_slave.bin -w

When I invoke the transmission program at the sender laptop using

sudo ./test_mimo_tx -f 2.412G -I a.dat -i 100 -r

I observe the following message:

usrp2::ctor reset_db failed.

The USRP2 freezes after this and the host cannot find it using find_usrps. The archives of the mailing list suggest updating the firmware to solve this issue. But I want to use the MIMO firmware and not the usual txrx.bin.

1. Is there firmware for the MIMO master and slave, which does not have this problem?

2. What modifications need to be incorporated to the current MIMO files to fix this problem?

If there is not a solution already, I am thinking of modifying the existing MIMO USRP2 related files. Any pointers on what are to be taken care of, will be very useful.



注:USRP2 MIMO setup problem - msg#00553 (英文原文出处,以上翻译整理仅供参考 Email: support@microembedded.com !)