3.3.2 Moving-average filter Moving-window averaging filter = Moving-average (MA) filter 3.3.1 Synchronized average  Ensemble average 3.3.2 Moving averaging  Temporal (time) average Ergodic : Temporal statistics may be used instead of ensemble statistics

Signal flow graph Figure 3.15

An example Figure 3.16

Suitable for PCG and EMG Not suitable for ECG (attenuation not high enough) Figure 3.17 Magnitude and phase response of the Hanning filter

Fs = 1 kHz Moving window Fs = 1 kHz

M = 8 Fs = 1 kHz 60 Hz 500 Hz

M = 26 60 Hz

M = 101 60 Hz

Frequency response of MA 8, 26, 101

Effect of N Fs = 1 kHz Original MA 8 MA 26 MA101

Transfer function of MA8

Transfer function of MA101

Signal flow graph

Estimation of signal frequency

Figure 3.18

Figure 3.19

Figure 3.20

Figure 3.21