Update to BBN 802.11b code 2Mbps transmission now supported


#1

Hi All,

I uploaded my latest code to the SVN. I implemented 2 Mbps (DQPSK)
packet
transmission and it works in simulation and with the USRP2. 1 or 2 Mbps
packets can be sent with the send_pkt function by selecting the bit
rate.
Please read the send_pkt function in the pkt.py file and the test.py for
examples of how to use the new send_pkt interface. All the code is in
the
CGRAN server under the usrp2_version branch. Note that this only works
between two USRP2s, not with 802.11b chipsets.

I have made some additional changes to the interface that I have not
tested
with the USRP2 itself, but it all works in simulation so it should work.
One
of my co-workers will be able to test it sometime soon as I dont have
access
to a USRP2.

Cheers,
Colby B.


#2

Great!

Thanks, and congratulations!
We’ll test it on Monday…
We are still working on the Barker implementation.
This week we have been able to transmit (1Mbps) to IEEE802.11b chipsets
with a modified version of your branch.
We have just changed the way the barker sequence is applied (credits to
Andrea, he might probably add some details later).

So far, our real 802.11b chipset receives almost everything sent from
the USRP2, if the packet_length is <100bytes.
Further increases in the packet_length lead to an (almost linear)
increase of PER.
When packets exceed 500bytes, almost nothing is received.

As soon as we figure out the reason of this, we can send to the list our
small modifications.

Cheers,
Danilo


#3

Great to hear on the Barker implementation! I am looking forward to see
what
changes were done to the Barker TX.

–Colby