[Discuss-gnuradio] FFT for FM Tx and Rx

[El El]

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

FMreceiver.jpg
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FMtransmitter.JPG
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