Continue to Site

Welcome to

Welcome to our site! is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

How can i calculate the SNR from the ADC data

Not open for further replies.


Newbie level 1
Aug 6, 2009
Reaction score
Trophy points
Activity points
calculation of snr in digital signal

Hello everyone,i have a problem with my ADC data.
I want to calculate the ADC's SNR,and i 've done FFT using MATLAB,i found some matlab program to calculate the SNR,but many of some can not work,so is there anyone can help me with it ,or tell me where i can find answers.
thank you very much!!


I got sigma delta modulator design (.mdl files) from my senior. I wanna simulate and have to calculate SNDR/SNR from fft plot using matlab. I'm using hanning window to get fft. I was wondering how to calculate snr/sndr/dr from matlab.

Thanks in advance

Hi all,

Sorry to bother you. I am new in this forum. I have the same problem of the calculation of SNR. Please help.

Sine wave is quantized and then I have calculated its SNR using FFT. The coherence condition with windowing as well is implemented to avoid leakage in the adjacent frequency bins.

I am unable to calculate the SNR accurately with different resolution of quantizer (ADC).

If I use a standard formula for quantization noise power (Q^2 / 12), the SNR corresponds with the theoretical formula of SNR (SNR = 6.02*NoOfBits + 1.76) but when I try to use my own calculated noise power, the SNR does not corresponds with the theoretical formula with different resolution.

I think, I am not calculating the noise power in the correct way. I have considered the noise spectrum starting from 2nd bin to input bandwidth.

By the way I am using the formula of SNR = 10*log10(RMS_of_Signal/Mean_of_RSS_of_Noise)


I remember calculating SFDR for 100 Mhz ADC. I see if I can find the C code for it and extrapolate equation and post it here. That might help you on the SNR.

Not open for further replies.

Part and Inventory Search

Welcome to