# Why is Frequency Shift Keying more immune to noise than ASK?

Is it because noise manifests itself in the transmitted signal's amplitude?

• Could you cite a reference for your claim that FSK is more immune to noise than ASK? – Dilip Sarwate Mar 13 '13 at 3:38
• We actually conducted an experiment on noise immunity of the different modulation techniques. We observed that FSK has lesser values of signal-to-noise ratios before the probability of error reached 0. – user4115 Mar 13 '13 at 3:55

• I actually read plot 1 in that reference exactly the opposite of does not give FSK a performance advantage over ASK ? For lower SNRs, ASK has a much higher error probability than FSK. – Peter K. Apr 13 '13 at 2:35