  With an increasing variety of measurement applications using sensing nodes on
unmanned aerial vehicles (UAVs), global positioning system (GPS) and global
navigation satellite system (GNSS) disciplined oscillators (GPSDOs, GNSSDOs)
are an appealing solution for precise wireless inter-device synchronization.
Typically evaluated under laboratory conditions by analyzing the 10 MHz and 1
pulse per second (PPS) reference signal stability, these test methods overlook
airborne oscillator performance. This paper characterizes lightweight GNSSDO
models for flight suitability using a measurement system based on software
defined radios (SDRs). We analyze reference signal stability under controlled
GNSS signal impairments to predict performance and measurement precision loss
in dynamic operational modes. Additionally, we assess behavior under the
impacts caused by operating the UAV, as well as typical flight vibrations and
accelerations outlined in the standard for payload devices.
