Re: [Discuss-gnuradio] OFDM Benchmark Tx Issue?

[Florian Schlembach]

> I highly suspect it's user error :) but I'm truly at a loss right now as to the 
> error.

Michael,
we encountered a very similar issue and spent already a lot of time on 
that. Configuration is the same except we are using an USRP2 though.

We also did not receive anything at the RX side although the spectrum 
looked quite good as we have checked that via usrp_fft.py.
Ultimately, we found out that it was about the sampling rate. We were 
able to receive something with a sampling rate (respective bandwidth ) 
from 1.5 MSamples/s, better 2 MS/s.
We are assuming that this might be a decimation rate issue. We facing 
the same problems with both a XCVR2450 and an RFX daugherboards. We 
checked whether lower sampling rates are working with both 
daughterboards (with another SDR implementation called Iris, also uses 
UHD) and they do! Thus, this might eventually be a problem of GNU Radio.

Could you check whether you are receiving something with higher sampling 
rates? Just invoke your benchmark scripts with a higher bandwidth, e.g. 
-W 2M

BRs, Florian