mitrobge
Member level 3
Have you any experience on idle tones of a feed-forward third order digital ΣΔ modulator?
From theory these tone will occur at:
f0=(n * Adc * Fs )/ (2Δ)
where n=1,2,3...
Adc is the amplitude of the dc signal
Fs is the sampling frequency (frequency of the modualtor)
and for a quantizer toggling between -1 and 1 Δ=2.
My Fs=6000 Hz and my zone of interest up to 1 kHz.
From Matlab simulations I believe that the higher the order of the modulator the less the amplitude of these tones in low frequencies.
I would appreciate your help.
From theory these tone will occur at:
f0=(n * Adc * Fs )/ (2Δ)
where n=1,2,3...
Adc is the amplitude of the dc signal
Fs is the sampling frequency (frequency of the modualtor)
and for a quantizer toggling between -1 and 1 Δ=2.
My Fs=6000 Hz and my zone of interest up to 1 kHz.
From Matlab simulations I believe that the higher the order of the modulator the less the amplitude of these tones in low frequencies.
I would appreciate your help.
