Decimation is certainly faster and simpler. There is an option to average between decimated point but beware of the nasty frequency response. If you really want or need to prevent aliasing and/or artifacts in the frequency domain apply a digital low pass filter with a break point at much less than your sampling frequency after decimation. If you really want to get fancy, reverse the signal, run it through a FIR filter, then flip it again (back to original) and run it through the same filter. Voila! zero phase filter with an extra boost at the stop band.
Philip
CLD
