I'm trying to convert the raw acceleration data into frequency weighted acceleration data.

According to ISO 2631:

The acceleration signal may be analyzed and reported as either constant bandwidth or proportional bandwidth (e.g.as one-third octave band) spectra of unweighted acceleration. In the case of one-third octave bands the centre frequencies shall be as stated in tables 3 and 4. Any form of frequency analysis, analogue or digital, direct one-third octave band or summation of narrow band data may be used. The data analysis method shall be consistent with the one-third octave band filter specification given in IEC 1260.

The frequency-weighted r.m.s. acceleration shall be determined by weighting and appropriate addition of narrow band or one-third octave band data.

For the conversion of one-third octave band data, the weighting factors given in tables 3 and 4 shall be used. The overall weighted acceleration shall be determined in accordance with the following equation or its digital equivalent in the time or frequency domain: $$a_w = \left[ \sum_{i}\left(W_{i}a_{i} \right)^{2} \right]^{\frac{1}{2}}$$ where $a_w$ is the frequency-weighted acceleration, $W_i$ is the weighting factor for the $i$th one-third octave band given in tables 3 and 4 and $a_i$ is the r.m.s. acceleration for the i th one-third octave band.

Since the raw acceleration data I have collected is in time-domain, I'm having trouble understanding how to select weights for each acceleration point using tables 3 and 4?

PS My knowledge in signal processing is limited but helpful suggestions could probably get me going.


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