Effect of Platform Dynamics on Aerial Layer Network Performance

In a tactical environment, disparate surface nodes are often unable to communicate effectively with each other through line-of-sight radios due to long distances and terrain blockages. The Joint Aerial Layer Network (JALN) consists of a set of unmanned aerial vehicles (UAVs) that provide surface range extension to surface nodes while also providing reach back to the Global Information Grid (GIG). These capabilities are achieved through a downward facing antenna that provides surface-to surface communications relay, as well as directional, high data rate crosslink antennas that connect the UAVs to each other. In this paper, we examine the implications of platform dynamics on crosslink availability and up/downlink coverage area in JALN. We study the availability for various orbital patterns and show that smaller orbits provide a larger high-availability coverage area. However, crosslink and up/downlink blockage is more likely during aircraft banking, which should be taken into consideration when designing an orbit. In addition to the orbital patterns, we also study how crosslink availability is affected by antenna placement. A single wing-mounted pod design suffers greatly due to field-of-regard restrictions. We compare the single active pod design with other options to improve performance including two active pods and body-mounted antennas.