DOI: 10.5281/zenodo.17100726
title: FR3 coherent multiband monostatic channel measurements

description: The dataset includes 475 over-the-air Channel Frequency Response (CFR) measurements obtained with a multiband monostatic transceiver spanning the frequency range 6-22 GHz. The transceiver sweeps the full frequency range, transmitting OFDM pilot signals with a bandwidth of 500 MHz or 1 GHz with different carrier frequencies. The dataset consists of 200 calibration measurements using a loopback cable (non over-the-air), 150 single-target over-the-air measurements, and 125 over-the-air multitarget measurements. We consider three target types: a calibrated corner reflector, a metal plate, and humans.  We collect our measurements in a laboratory environment where we cover walls, furniture, and the support of the targets with panels made of RF absorbing material.

Measurement system

We utilize a Software Defined Radio (SDR) platform in monostatic configuration, using 1 transmit and 1 receive chains.

The SDR includes the following components:



Digital baseband RFSoC: A Xilinx Radio Frequency System on a Chip (RFSoC) 4x2 Kit equipped with a ZU48DR processor is used for baseband signal processing, including digital-to-analog (and vice-versa) conversion. The board is capable of generating Radio Frequency (RF) signals up to 6 GHz, and therefore cannot directly generate FR3 signals. It is instead utilized to generate an Intermediate Frequency (IF) signal centered at 1 GHz that is up/down converted in a later stage.

RF transceiver Pi-Radio board: The IF signal generated by the RFSoC 4 × 2 Kit is up/down converted by a Pi-Radio TRX board, which translates the fixed-frequency IF to a configurable frequency in the 6-24 GHz range, enabling the frequency sweep. The up and down conversions are performed coherently, ensuring consistent phase measurements.

Vivaldi wideband antenna: The measurements are performed over a bandwidth of over 15 GHz centered around 14 GHz, which constitutes a fractional bandwidth greater than 100%. Such a fractional bandwidth is difficult to achieve with standard antennas such as patches or dipoles, which usually provide a percentage fractional bandwidth in the order of units to a few tens. To address this, we use a wideband Vivaldi antenna which, thanks to its exponentially tapered structure, can operate across the whole 6-24 GHz band.


Frequency sweep

To configure the RFSoC and Pi-Radio board, we use he code available at https://github.com/ali-rasteh/RFSoC_SDR.

To obtain coherent CFR estimates over the bandwidth 6-22 GHz, we use the Pi-Radio FR3 board to implement a frequency sweep across the full bandwidth. This is done by transmitting random OFDM pilot signals from a 4-Quadrature Amplitude Modulation (QAM) modulation over a configurable bandwidth centered around a configurable carrier frequency The carrier frequency is changed in subsequent OFDM symbols. The switching between different carrier frequencies requires tswitch = 10 ms in the Pi-Radio board, so this is the minimum timing between OFDM symbols that can be configured in our measurements.In our experiments, we use two different bandwidth values 0.5 or 1 GHz, depending on the specific experiment. We select the carrier frequencies to obtain a contiguous setof CFR estimates. When using 0.5 GHz, we select the set {6.5, 7, . . . , 22} GHz, with 32 subbands, while using 1 GHz we select {6.5, 7.5, . . . , 21.5} GHz, with 15 subbands.The different cardinality of the two sets has the important consequence that the total duration of the frequency sweep using 0.5 GHz is 32tswitch = 320 ms, while using1 GHz it is 15tswitch = 150 ms. For this reason, we use 1 GHz in the measurements involving human targets since a shorter total measurement time is preferable to avoidincoherence due to small involuntary movements of the person.

Considered targets



Corner reflector: We use a corner-cube reflector with 15 cm side length. The corner reflector is calibrated for radar applications.

Metal plate: We use a flat metal plate of dimensions 25 × 10 cm. The thickness of the plate is a few millimeters.

Static human: Human subjects are instructed to stand as still as possible in front of the measurement device. To mitigate the impact of respiration on the phasemeasurements, they are asked to hold their breath for 2-3 seconds during the data collection, which lasts 150 ms for the full frequency sweep.


Dataset information

Information about each test, the employed bandwidth, the target types and locations can be found in file measurements_info.xlsx. CFR measurements are provided in .npz format according to the following naming convention

test_09_07_2025_TEST_XXX.npz

where XXX is the test number referenced in the first column in measurements_info.xlsx. Different test numbers correspond to different targets, and experiments.

Each .npz file contains a field "txtd" with the transmitted signal in the time domain and 32 or 15 files containing the received signals (depending on whether 0.5 or 1 GHz are used). In the script data_loader_zenodo.py we provide a minimal example of how to load the CFR for each subband and estimate the CIR.

Reference

If you use this dataset in your work, please cite our associated paper

@article{pegoraro2025toward,
  title={Toward Multiband Sensing in FR3: Frequency Anisotropy Characterization and Non-Contiguous Bands Aggregation Algorithms},
  author={Pegoraro, Jacopo and Ventura, Gianmaria and Tagliaferri, Dario and Mezzavilla, Marco and Bedin, Andrea and Rossi, Michele and Widmer, Joerg},
  journal={arXiv preprint arXiv:2510.03787},
  year={2025}
}