Re: [Discuss-gnuradio] query about fm example file in github tutorials repository

Hi Jacqueline,

judging from the file name (_1Msps), the sampling rate is 1 MS/s. When it comes to signal bandwidth – a complex 1MS/s stream can contain up to 1 MHz of bandwidth, but FM broadcast radio stations typically use something like 75 kHz of bandwidth for their FM signal.

Best regards,

Marcus

On 06/29/2017 04:39 PM, Jacqueline.Walker wrote:

Hi,

 

I downloaded the file fm101.8MHz_1Msps.cfile (from gr-tutorials/examples/tutorial6/ ) to use for trying out demodulation flowgraphs in gnuradio. It was recommended here: https://wiki.gnuradio.org/index.php/Guided_Tutorial_Hardware_Considerations

But I can't find any details about the file – it says on the tutorial page – 'an actual recording from a radio (USRP I presume) with nothing done to the data, so I presume it is just a binary stream such as one would receive from a USRP and that the centre frequency is 101.8MHz. What is the sample rate output by the USRP that recorded the file – is it 250k as given on the tutorial page? What is the signal bandwidth expected? I ask this because I don't see that much on the FFT?

 

Thanks

Jacqueline

_______________________________________________  Discuss-gnuradio mailing list  Discuss-gnuradio@gnu.org  https://lists.gnu.org/mailman/listinfo/discuss-gnuradio