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General Information
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This file is meant to describe the structure of the data used to obtain the results of Fig. 3 and Table III of the research article "Natural Frequency Dependence of Magneto-Mechanical Resonators on Magnet Distance" (https://doi.org/10.1109/JSEN.2025.3600007) from J. Faltinath, F. Mohn, F. Foerger, M. Möddel and T. Knopp published in the IEEE Sensors Journal, Volume 25, Issue 20.

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Data File Structure
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The raw measurement data are digitized induction voltage signals which are saved together with relevant metadata of the measurement sequence in a hierarchical data format based on the HDF5 standard. This format is called .mmr, follows a defined structure and can be analyzed with standard libraries, e.g. "HDF5.jl" in julia or "h5py" in python. The hierarchy of such an exemplary measurement sequence file with name "D1.mmr" is the following:

D1.mmr
|_...
|_data
|_sequence
  |_...
  |_baseFrequency
  |_...
  |_decimation
  |_...
  |_numRxSamples
  |_numSwitchSamples
  |_numTxSamples
  |_...
|_...

Note that only the groups and datasets are highlighted which are relevant to obtain the time vs. induction voltage signals. 

A measurement sequence consists of repeated measurement frames and each frame is again divided into an excitation window (Tx), switching window (Switch) and receive window (Rx). 

The dataset "data" contains the digitized measurement values (samples) in volt induced in the experimental coils for the whole measurement sequence, i.e. for all frames and including the full excitation, switching and receive windows. The first dimension of "data" represents the frame number, the second dimension corresponds to the coil channel number (sorted in the order of v-, u- and w-coil pair) and the third dimension represents the index of the sample inside a frame (starting with the excitation window samples, followed by the switching window samples, and ending with the receive window samples). The total sample number is equal to the sum of "numTxSamples" (number of samples during excitation), "numSwitchSamples" (number of samples during switching) and "numRxsamples" (number of samples during receiving). The sampling frequency can be calculated by dividing the "baseFrequency" with the "decimation". Correspondingly, the time point inside a measurement frame is given by dividing (sample number - 1) with the sampling frequency.

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Data Filtering
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For the analysis, only the samples during the receive window were used, i. e. starting with the sample number (numTxsamples + numSwitchSamples + 1). Furthermore, only the signals of the v- and u-coil channel, i. e. coil channel 1 and 2, were processed.

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Data Directory Structure
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This respository contains the measurement data for the three magneto-mechanical resonators (MMRs) of the study as individual folders, labeled as Sphere-, Cylinder- and Hybrid-MMR. Each folder again consists of fourteen different files with ascending naming convention from D1.mmr to D14.mmr, each corresponding to the measurement sequence file of a different magnet distance. The following center-to-center distances were realized:
D1 	= 	10.0 mm
D2 	= 	9.375 mm
D3 	= 	8.75 mm
D4 	= 	8.125 mm
D5 	= 	7.5 mm
D6 	= 	6.875 mm
D7 	= 	6.25 mm
D8 	= 	5.625 mm
D9 	= 	5.3125 mm
D10 	= 	5.0 mm
D11 	= 	4.6875 mm
D12 	= 	4.53125 mm
D13 	= 	4.375 mm
D14 	= 	4.21875 mm