Sine Waveform: Harmonic in FFT

Status
Not open for further replies.

jasonkee111

Junior Member level 3
Joined
Feb 8, 2009
Messages
28
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,501
Hi. I have a set of data of 22k sine wave feed it to fft. The result is
very smooth as shown in attachment fft magnitude. However, when i do the
0.5sin22k, it results of a lot of harmonic in attachment fft_0.5sin22k.

May i know the reason causing this?


FYI, the set of data of sin22k is in integer form.

When i do the 0.5sin22k, i only take the integer output by truncating the fraction. i did some zero padding. It is due to my sin generator can generate 24 bit output. In order to multiply with a fraction(precision
0.001), i add another 10 bit (zero padding).
 

sorry. I have found out the problem. There is something wrong with my raw data.

Thanks
 

Status
Not open for further replies.

Similar threads

Cookies are required to use this site. You must accept them to continue using the site. Learn more…