The impact of intersatellite communication links on LEOS performance

LEOS communication systems are rapidly moving from dream to reality. When operational, the LEOS systems can offer mobile and fixed-site communications between any two points on the globe. Yet, many LEOS system design issues remain unresolved. Some of the planned systems, such as Iridium and Teledesic, rely on intersatellite communication to provide space based routing from origin to destination while others, like Globalstar, use ground based routing. This paper investigates the effect of satellite crosslink design on user-to-user delay and satellite power consumption. Delay is an important measure of quality of service and may have a significant impact on system revenues. The results indicate that the choice of crosslink architecture has a large effect on user-to-user delay. In a polar orbit LEOS system, there will be two seams from pole to pole 180◦ apart, where satellites in orbits on opposing sides of the seam move in opposite directions. It is demonstrated that the ability to maintain communication links across the seams is of relatively minor importance for user-to-user delay. Finally, the choice of crosslink pattern and crosslink antenna technology is shown to have no significant impact on satellite power consumption or on LEOS system capacity. Telecommunication Systems Journal– In Print