I have run another test on a single stationary sensor. I am trying to replicate the results in the datasheet. In table 10 it reads that I should expect an RMS noise of 5cm under the following conditions: Pressure oversampling: x16 Temperature oversampling: x2 IIR filter coefficient: 4 RMS measured over 32 consecutive measurement points taken at highest sampling rate in a controlled pressure environment The datahseet uses the term "average standard deviation" in paragrpah 3.4.4 but the term RMS in table 10. I have calculated the standard deviation over the 32 consecutive measurements and get results very much in line with the specifications: a standard deviation below 4cm. The problem is that the moving average (over 32 consecutive measurements) does not stay within a min-max range of that order. Instead, it fluctuates over a range of 70cm (over a measuring interval of 5 minutes). In this image you can see a summary of the results: And here is the legend for the colors in the range Red: Max value of moving average Green Min value of moving average Orange Moving average Blue Moving average - half the moving standard deviation Grey Moving average + half the moving standard deviation Since I cannot control the pressure in my environment, part of the fluctuations in altitude may be explained by fluctuations in the atmospheric pressure. Before I conduct other tests, I'd like to know if this falls within expectations: can atmospheric pressure fluctuate so much within 5 minutes? Or are these results in line with the sensor capabilities?
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