Coherent average technique--a tutorial review.
This paper highlights the effects of digitization in relation to the effective numberical range over which the signal to be averaged has to be resolved. The effect of quantization noise on the number of averaging cycles is assessed and it is shown that for averaging weak signals such as the HIS bundle electrogram, high resolution analogue-to-digital (A/D) conversion is required so as to prevent a substantial increase in the number of averaging cycles. Also the requirement for adequate low-pass filtering is discussed and relationships between the numerical range of the A/D conversion process, the order of the low-pass filter, its cut-off frequency and sampling frequency are formulated.
Goovaerts
H G
HG
Department of Medical Physics, Medical Faculty, Free University, Amsterdam, The Netherlands.
Rompelman
O
O
D000703:Analog-Digital Conversion; D012815:Signal Processing, Computer-Assisted