Effect of Automatic Dependent Surveillance Broadcast (ADS-B) Transmission Quality on the Ability of Aircraft to Maintain Spacing in a Sequence

摘要

The effect of ADS-B update rate, latency and accuracy on the airborne spacing performance of a sequence of six aircraft in descent was investigated using fast time simulation. Two different spacing criteria based on constant distance (7 nmi) and constant time delay (60 s) were evaluated using a spacing guidance law between aircraft. The performance of three different compensation terms for ADS-B update rate, latency and accuracy was also assessed. Spacing performance indicators used were distance or time between aircraft, speed variation and throttle behaviour. Results show that constant time delay spacing remained more stable than constant distance spacing for degradations in ADS-B update rate, latency and accuracy. Constant distance spacing was sensitive to the quality of ADS-B aircraft position information whereas constant time delay spacing was sensitive to the quality of ADS-B aircraft position and speed information (particularly speed accuracy). Transmission loss compensation terms for update rate, latency and accuracy produced significant improvements in spacing guidance stability.