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Altera_Forum's avatar
Altera_Forum
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16 years ago

White Noise Spectrum

I have use a simple LFSR to generare random number to generate white noise. Set of random number are pass through to FFT(power in db vs freq). However, the freq response is increasing at low freq. Th...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Previously attachment only take 1024 point for FFT.

I use the 16bit to generate the random numbers. So, it generates 65535 random number and it repeats.

The attachment below i take 65535 point for FFT

Even though use different set of length(bit), the power spectrum still increasing at low freq(curve going up)

WK:

Quote

"you perform more clk cycles between sampling random numbers"

I din get it. Can you explain more?

thepancake:

Quote

"if you'd rather see the tapering near the half sample rate, flip the sign of every other sample. in this case i think you'll have a DC offset."

I have no idea abt it. Can you explain in details?

thanks a lot