Re: [Discuss-gnuradio] OFDM on USRP2

[Josh Blum]

> I use two USRP2s. When the receiver is loaded with the UHD driver it
> exhibits poor performance. No matter if the sender is using the
> standard or the UHD driver.
> 

I was under the impression that performance meant high cpu load, too
many overflows/dropped packets. I think you mean that the app with UHD
has poor reception of the OFDM packets?

If thats the case, I think UHD is ok; and perhaps this is an issue of
something gets tuned differently, or some gains get set differently, or
the issue of the drifting clock. Have you tried a external 10mhz reference?

> The buffer shouldn't be the problem:
> 
> "Current recv sock buff size: 50000000 bytes"
> 

ok, thats expected

> I do get that filtering warning, though:
> 
> "Warning:
>     WBX: No tunable bandwidth, fixed filtered to 40MHz"
> 

this is a result of calling set_bandwidth() on WBX

-Josh