ECG Compression - ECG Acquisition and Automated Remote Processing - page 112

Fig. 5.9 Original and reconstructed quantized signal with different threshold

0.39 %, the CR is doubled in most of the cases with an increase in PRD. Figure 5.9
represents one such ptb-db data reconstructed with and without threshold.
It is observed that the TP and PQ regions have flattened much due to threshold;
however, the CR will also increase. Table 5.8 shows the performance of 8-bit
quantized ECG compression performance with and without threshold.
However, using a threshold level of 0.78 %, it was found the reconstructed
waveform is totally distorted [ 38 ].

5.4 GSM Communication for ECG Transmission

In this section, a GSM communication system is illustrated for ECG transmission
to a remote mobile phone using the principle illustrated in Sect. 5.3 . The objective
is to capture a short duration (3-4 beats) ECG, compress the same, and send to a
remote cardiologist in the form of short messages to his mobile phone. The
received massages can be downloaded to the laptop or desktop for concatenation,
decoding and generating the ECG for the cardiologist.