Connection Admission Control CAC and Differentiated Resources Allocation RA in a Low Earth Orbit LEO Satellite Constellation

摘要

The Up/Down Link UDL of a Low Earth Orbit LEO satellite constellation is a scarce radio resource that needs to be shared efficiently between many users with different needs. A suitable Connection Admission Control CAC policy is required. In our study we assume that the network handles three types of calls: real time (voice) calls with strict constraints over the delay and the bandwidth, non real time (data) calls delay tolerant but with bandwidth guarantees requirements and Best Effort calls with no guarantees requirements. In order to ensure priorities are respected, we use an "enhanced trunk reservation policy" in order to derive the Resources Allocation RA. A differentiated RA scheme is proposed, associated with queuing for the lower priority calls. Different unity bandwidths are associated with calls depending on their requirements. The analytical markovian model is first derived, then the differentiated RA model is compared with two cases of bandwidth granularity choice. Impact of non markovian laws is studied using simulation.