Hi Vincint, Using 230Hz LPF does provide a lower noise level. However, as we talked before, the data from 230Hz has spikes in the low frequency part in the PSD plot while data from 523Hz does not. So I would like to use 523Hz LPF and aply my own filter. However, the 523Hz data has a much higher noise level. According to the datasheet, the noise density is 0.014dps/sqrt(Hz). For 230Hz bandwidth, the RMS should be 0.014*sqrt(1.22 * 230) = 0.23dps, where 1.22 is from the equation FAE_CA1 provided. For 523Hz bandwith, the RMS should be 0.014*sqrt(1.22*523) = 0.35dps. Actually, the RMS of 523Hz data is much larger than that. What I can see is that the 230Hz LPF not only reduce energy beyond 230Hz but also attenuates frequency from 0 to 230Hz, which is weird. Please refer to the red and yellow lines in the figure below. I zoomed in the plot to show only the low frequency. Thank you.
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