Air-to-Air Channel Characterization for UAV Communications at 3.4 GHz
This work addresses the need for accurate A2A channel models for UAV networks, which is incremental as it builds on existing Air-to-Ground work by providing specific sub-6 GHz data.
The paper tackled the problem of poorly characterized Air-to-Air (A2A) channels for UAV communications at sub-6 GHz by presenting preliminary 3.4 GHz measurements using a custom-built channel sounder on two UAVs, resulting in analysis of channel properties like RMS delay spread and fading statistics to inform protocol design.
Uncrewed Aerial Vehicle (UAV) networks require accurate Air-to-Air (A2A) channel models, but most existing work focuses on Air-to-Ground links and leaves the sub-6 GHz A2A channel poorly characterized. We present preliminary 3.4 GHz A2A channel measurements collected with a lightweight, reconfigurable, open-source channel sounder built from USRP B210 software-defined radios and a high-precision GNSS-disciplined oscillator mounted on two UAVs. Measurements were conducted at the AERPAW Lake Wheeler testbed using a spherical flight trajectory around a second drone to capture channel behavior over varying altitudes, elevation angles, and relative headings. From these data, we analyze fundamental channel properties, extract channel impulse responses, model fading behavior as a function of link geometry, and characterize fading statistics including RMS delay spread. The resulting dataset and analysis provide a more realistic basis for the design, emulation, and evaluation of physical-layer and MAC protocols for next-generation UAV communication networks.