Optimized Positioning of ECG Electrodes for WSN Applications - Application and Multidisciplinary Aspects of Wireless Sensor Networks - page 184

Currently, MECGs are mostly experimental devices with no accepted standard as
to the number of electrodes and their location. The number of MECG electrodes
ranges from 10 to 300. Their placing is mostly based on the equidistant four neigh-
bors mesh. We have developed a custom MECG [ 6 ] with either 31 or 35 electrodes,
placed as shown in Figs. 9.5 and 9.6 and all referenced to the Wilson's central ter-
minal potential. The two sets of placements are similar; however, that in Fig. 9.6
was adopted for patients with limited mobility. High-precision input amplifiers and
filters are used for conditioning the input signals, and a 16-bit A/D convertor was
applied for the conversion of input analogue signals to digital data. The sampling
rate of each channel is 1,000 Hz. The battery-powered measuring device is
connected optically to the computer system, which is responsible for data acquisi-
tion, visualization, and analysis.

FRONT BACK

9 13 25

6 10 4 7 22 26 29

4 7 11 15 18 20 23 27 30

5 8 12 16 19 21 24 28 31

B C

EFGH I J

D

1-RIGHT ARM 2-LEFT ARM 3-LEFT LEG -> A

Fig. 9.5 Multichannel ECG (MECG) positioning of 31 electrodes

FRONT

32

13 21 28

17

4

7

25 33

10 14 18 22 29

5

8

19

11 15 23 30 34

26

9 12 16 24 31 35

6 27

20

0-RIGHT LEG 1-RIGHT ARM 2-LEFT ARM 3-LEFT LEG

Fig. 9.6 Multichannel ECG (MECG) positioning of 35 electrodes