# Data and code for "Same Signal, Different Story: Demystifying Receiver Effects in Wi-Fi Channel State Information"
The dataset(s) here were collected with a Wi-Fi testbed of eight different receivers:
The transmitter for all the datasets is another USRP N2954-R with Wi-Fi frames generated using the MATLAB WLan Toolbox.
All data was collected using our python scripts, published on GitHub: https://github.com/nzqo/sensession.
Relevant subprojects for CSI extraction are found in `csi_tools` in sensession.
You can find the experiment design (e.g. frame precoding) by inspecting the `/experiments` directory.
Evaluation scripts of the data are also shared in the `/evaluation` directory.
## Format
All data is stored as `.parquet` files, which is tabular data. Each line contains a single CSI recording. The `meta_id` column marks a group (a coherent recording), with further information linked in the corresponding `meta.parquet` files. These files can be easily loaded into dataframes using e.g. pandas or polars.
Every CSI value is represented as a nested list corresponding to shape `[num_antennas, num_streams, num_subcarrier]`.
## HAR dataset
The HAR dataset comes with a dedicated README with more information on the contents.
## Over-the-wire data
For the OTW data, all devices are connected to the transmitter using cables of equal length, feeding the signal through a waveguide powersplitter (ZN8PD1-63W-S+). Archive names describe the measurements we ran (e.g. single subcarrier modifications).
%I 4TU.ResearchData