The ability of autonomous unmanned aerial vehicles (aUAVs) to carry out a diverse range of missions presents enormous societal and economic benefits. However, one critical safety issue that must be addressed prior to large-scale aUAV adoption is the potential for aUAV-on-aUAV trajectory conflicts. Current decentralized methods for trajectory conflict resolution are energy and resource intensive, rendering them difficult to scale and implement. We propose a centralized, infrastructure-to-vehicle (I2V) approach that leverages modular embedded systems (“control modules”). A voxel-based airspace reservation system is maintained by the control module, which interrogates and retrieves the stored trajectories from aUAVs approaching the reservation airspace. Trajectory conflict search is performed by the control module, and conflict resolution protocols are transmitted back to the aUAVs. Our communication protocol is Wi-Fi-based and leverages a lightweight on-board ODROID microcontroller; the setup is agnostic to the specific aUAV platform and firmware. We simulate various airspace situations and test the resiliency of our reservation system in MATLAB. We also leverage two aUAV testbeds to demonstrate the performance of our centralized air traffic control regime.