Hi Guat-Eng! SNR is the quality measure for a single but composite waveform. One part of such a waveform is declared as signal and the rest is noise. Then, it is possible to calculate the SNR as the ratio of "signal" power and "noise" power (or their difference i dBs). Two signals, input and output, can be compared in their amplitude (gain or attenuation) or in their quality (SNRs). That means, calculate SNRi for input signal [dB], SNRo for output signal [dB], and make a difference SNRi - SNRo. That's analogous to noise factor (noise number). Predrag Valozic ----- Original Message ----- From: egan_nc <> To: <> Sent: 2003. ozujak 18 22:40 Subject: [matlab] SNR > Hello, > Please can someone help me with this question? > I generate a 6kz sin wave and design an ideal filter using remezord > and remez with cutoff frequency of 6.5k and 8khz. The filtered > output in time domain matched the original signal. So is the fft > output. My question is how do I calculate the SNR between these two > signals? Do I do it in time domain or frequency domain? I know the > formula for calculating the SNR = 20log10(sum(x)2 sum(x - x')2) > where x is the original signal and x' is the filtered signal. > In frequency domain since the original signal is range from -300db > to 36db, and the filtered signal range from -10db to 60db. How do I > calculate the SNR? > Thank you in advance. > Guat-Eng Gan > _____________________________________ > Note: If you do a simple "reply" with your email client, only the author of this message will receive your answer. You need to do a "reply all" if you want your answer to be distributed to the entire group. > > _____________________________________ > About this discussion group: > > To Join: > > To Post: > > To Leave: > > Archives: http://www.yahoogroups.com/group/matlab > > More DSP-Related Groups: http://www.dsprelated.com/groups.php3 > > ">http://docs.yahoo.com/info/terms/ > |