Re: [Discuss-gnuradio] OFDM receiver on USRP2

[Matt Ettus]

On 02/12/2010 03:53 PM, Srinivas wrote:
> Matt,
>
> There was a frequency offset of ~30 KHz at the Rx w.r.t Tx so I
> compensated for it and it worked!.
>
> The settings I am using is as follows:
>
> ./benchmark_ofdm_tx.py -f 2.45G --tx-amplitude 0.9 -M 8 -s 200 -m bpsk
> --fft-length=512 --occupied-tones=80 -i 64 --tx-gain=10 --cp-length=128
> ./benchmark_ofdm_rx.py -f 2.45G -m bpsk --fft-length=512
> --occupied-tones=80 -d 64 --rx-gain=20 --cp-length=128
>
> I calculate the data-rate for OFDM as follows Data rate R = (ADC
> sampling rate x Occupied Tones) / (Nfft x Decimation)
> For the above setting it is 244 KHz.
>
> Am I right with the data rate calculation ?

That formula will give you the number of occupied tones per second.  You 
need to multiply by the number of bits per tone to get bps.  If you are 
using BPSK, multiply by 1.  If using QPSK, you'll need to multiply by 3, 
8PSK by 3, etc.

Matt