Analysis of Multislot Spread Spectrum ALOHA for Satellite Short‐Burst Communication

Satellite short‐burst communication is a key complement to terrestrial networks in maritime, mountainous, and emergency scenarios. In existing satellite random access systems, Pure Spread Spectrum ALOHA (Pure SSA) is simple to implement but suffers from low resource utilization, whereas ideal Slotted Spread Spectrum ALOHA (Slotted SSA) improves throughput at the cost of forcing large numbers of terminals to start transmission at the same instant, which increases receiver‐side signal discrimination and code‐allocation pressure under massive access. To bridge these two operating extremes, this paper studies a Multislot Spread Spectrum ALOHA (Multislot SSA) protocol based on cross‐microslot transmission. The packet start time is constrained to microslot boundaries, whereas each packet spans m consecutive microslots, so the parameter m provides a tunable trade‐off between asynchronous access and fully synchronous slotted access. An analytical model including the finite demodulation‐channel constraint of the central receiver is established under Poisson traffic, and the packet success probability and system throughput are derived. Monte Carlo simulations are used to validate the analytical results. Under the present assumptions, Multislot SSA occupies an intermediate operating point between Pure SSA and ideal Slotted SSA: Its throughput remains below the ideal slotted upper bound but above that of Pure SSA, whereas its distributed start phases provide a more implementation‐friendly access structure. The results provide theoretical support for the design of massive random access in satellite short‐burst communication systems.