Orbital Slot

An orbital slot is a designated longitude position in the geostationary orbit arc, assigned and coordinated through the ITU to prevent radio frequency interference between neighbouring satellites. Satellites must perform station-keeping to remain within their assigned slot (typically ±0.1°). Slots over densely populated regions (North America, Europe, East Asia) are the most commercially valuable, as they provide the best signal geometry for ground users. Nations and operators file for slots years in advance. The increasing congestion of the GEO arc has led to colocation — placing multiple satellites within a single slot — and tighter frequency coordination requirements.