My current work is about analyzing vibration is a signal from an accelerometer in a moving vehicle. After some math operations we get a signal that represents the vertical displacement of the vehicle versus travel distance. No big deal. We want to locate ithe intervals where excess vibration occurred, in a certain frequency band (loose), and have applied Discrete Wavelet Transform to that effect. Analyzing the coefficients in that frequency band we can locate the intervals where the vibration was higher. The thing seems to be working as planned, with actually pretty good and motivating results. Now come our doubts: why look at the coefficients (which time resolution has been reduced, depending on the level you are) and not reconstruct the signal corresponding to that coefficients, therefore gaining the original time resolution and squaring it (to get energy, likewise with the coefficients). So, the question is basically should we reconstruct the signal and square it to get energy, or use the wavelet coefficients which represent energy, anyway. Thanks in advance for your input. Palmar
Wavelet doubts about the coefficients
Started by ●March 5, 2010