In one implementation, a method includes receiving simulated RF transmission data indicative of anticipated RF transmissions from a plurality of transmitters, wherein individual anticipated RF transmissions carry corresponding messages, and simulated position data indicative of an anticipated position of each of the plurality of transmitters. The method further includes modeling characteristics of a communications channel expected between a satellite-based receiver and at least some of the transmitters, wherein the satellite-based receiver is configured to define one or more beams for receiving anticipated RF transmissions. The method additionally includes determining a likelihood of the receiver successfully extracting one or more components of a message from one of the anticipated RF transmissions based on at least the simulated RF transmission data, the simulated position data, and the modeled characteristics of the communications channel.