Issues regarding Simulink

[timbu007]

Dear All,
I am working on FFT plot for an ADC.While plotting i figured out that the input signal which is a sine wave is not providing the actual sine wave output.On verification of the FFT for the sine wave signal there is a spike at a vale of 3.3*10e8 .Attached is the figure. I am giving an input sine wave of 100e6*2*pi rad/sec using the sine wave generator block in Simulink. Any suggestions.Is it because of any conversion issues regarding frequency to radian sec.In the fft code my clock frequency is given as 1e9.
Really need our suggestions on this issue.
Thanks.

 

[eladla]

Ahh...
Sorry to tell ya, but 100e6*2*pi =~ 3.3*10e8

Or am I missing something?

 

[timbu007]

Dear Sir,
Thank you for bringing that to my notice.
I wanted to know how does the input frequency change the SNR of the ADC.In my case the SNR varies from negative to positive value as and when I change the input frequency at the sine wave generator.

Regards
Tim

Ahh...
Sorry to tell ya, but 100e6*2*pi =~ 3.3*10e8

Or am I missing something?