okogidi,
yes, Multisim can perform Noise analysis on a circuit (simulate->analysis->noise analysis). Resistor thermal noise and Semiconductor shot noise are modeled when performing this analysis.
Your SNR is simply the signal power at some node divided by the total noise power that noise analysis calculated.
There's an excellent tutorial on how to perform noise analysis in SPICE at http://ecircuitcenter.com/Circuits/Noise/Noise_Analysis/res_noise.htm
Thanks,
Max
Max
National Instruments
