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Development of a wavelet-based algorithm to detect and determine ...

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6.2. BASIC IDEAS OF THE WAVELET TRANSFORM 47<br />

Calculation <strong>of</strong> the Continuous Wavelet Transform<br />

The calculation <strong>of</strong> the continuous <strong>wavelet</strong> transform is a quite simple process. There<br />

are five steps:<br />

1. Chose a <strong>wavelet</strong> <strong>and</strong> locate it at the start section <strong>of</strong> the original signal.<br />

Figure 6.9: Step 1 <strong>of</strong> the continuous <strong>wavelet</strong> transform<br />

2. Calculate a <strong>wavelet</strong> coefficient according <strong>to</strong> Equation 6.6.<br />

3. Shift the <strong>wavelet</strong> <strong>to</strong> the right <strong>and</strong> repeat step 1 <strong>and</strong> 2 until the whole signal is<br />

covered.<br />

Figure 6.10: Step 3 <strong>of</strong> the continuous <strong>wavelet</strong> trans-<br />

form<br />

4. Scale the <strong>wavelet</strong> <strong>and</strong> repeat step 1 through 3<br />

5. Repeat step 1 through 4 for all scales.<br />

With the help <strong>of</strong> the <strong>wavelet</strong> transform, a one-dimensional signal can be represented<br />

in two-dimensional domain. Figure 6.12 shows, as an example, the <strong>wavelet</strong> domain

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