Hi El,

this is a bit hard to tell -- are you using a direct cable or antennas
between TX and RX?
If you're using antennas, that might simply be something else
transmitting there.

Also, if you transmit at 560 MHz, but only observe
$\SI{562}{\mega\hertz}\pm\frac{\SI{0.2}{\mega\hertz}}{2}$, you can't see
your transmit signal, so I can't compare the strength of that and what
you see in your RX FFT plot.

Best regards,
Marcus

On 06/21/2015 03:47 PM, El El wrote:
> Hi,
> I implemented the FM transmitter and receiver from the tutorials
> (http://files.ettus.com/tutorials/labs/Lab_1-5.pdf), the carrier
> frequency is 560 MHz, audio rate = 48 kHz, and frequency deviation = 5
> kHz. My question is why don't the FFT plots look similar? The FFT for
> the transmitter is centered on 562 MHz, but for the receiver, the
> highest amplitude component is centered on 561.97 MHz, also there is
> one more component on 562.09 MHz. Screenshots of the FFT plots are
> attached.
> Thanks a lot,
>
> El
>
>
>
>
>
>
>
>
>
>
>
> _______________________________________________
> Discuss-gnuradio mailing list
> Discuss-gnuradio@gnu.org
> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio

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

Reply via email to