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Example 13: A Triangle + A Sine + Noise

Noise Analyzing wavelet: db5

Decomposition levels: 7

The signal examined here is the same as the previous signal plus a uniform white noise divided by 3. The analysis can, therefore, be compared to the previous analysis. All differences are due to the presence of the noise.

D1 and D2 are due to the noise.

D3 and especially D4 are due to the sine.

The higher level details are increasingly low, and originate in the noise.

A7 contains a triangle, although it is not as well reconstructed as in the previous example.

Example 13: A Triangle + A Sine + Noise
Addressed topics
  • Detecting long-term evolution
  • Splitting signal components
Further exploration
  • Increase the amplitude of the noise.
  • Replace the triangle by a polynomial.
  • Replace the white noise by an ARMA noise.


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