Re: [Discuss-gnuradio] Sample receive time in benchmark

[Harry Zhang]

于 2013/9/19 21:56, Tom Rondeau 写道:
> On Wed, Sep 18, 2013 at 11:32 PM, Harry Zhang <address@hidden> wrote:
> > Hi,
> > My last question
> > (http://lists.gnu.org/archive/html/discuss-gnuradio/2013-09/msg00196.html)
> > seems no answer.But I get another question.
> > I wanna know the actual receive time of a sample. If I get the rx
> > tag(sample count 100), I can calculate the any sample's receive time.
> > For example,sample 1600's receive time: (1600-100)*sample_rate.
> > Is it correct?
> Yes, as long as you are using the right sample rate.
>
> > In my last question, the sender transmit data every 3 second and the
> > uhd_fft shows it's true.But the above formula give the result about 1
> > second.
> > I think the sample_rate is wrong. I'm using benchmark_rx(gmsk) in
> > narrowband and the UHD shows the sample_rate is 200ksample/s.
> > Sample_rate wrong or my formula,which is wrong?
> > Any suggestion is appreciated.
> Make sure you are using the sample rate and not the symbol rate. Each
> symbol is transmitted using some number of samples per symbol. I'm
> sure you already know that, but just to make sure as that's a likely
> cause of confusion when setting things up.
If I'm using the symbol_rate, the actual sample_rate must be more that 
that I'm using now. Thus the formula gives result even less than 1 
second, which is still not coming to 3 second.