Satellite Spot Beam and Decollision Algorithm for Pure Collective Aloha MAC Protocol

Modern satellite random access protocols require advanced medium access control (MAC) protocols to achieve high system throughput. There are both asynchronous and synchronous satellite MAC protocols in the literature. The former MAC protocols do not require packet slot boundaries alignment using a synchronization mechanism. Here, our key contributions are a proposed Pure Collective Aloha MAC protocol with Decollision Algorithm (DA) and Spot Beam (SB) (PCA-DA-SB) and its closed-form throughput formulation. This is an asynchronous MAC protocol. A batch of packets is buffered before being transmitted sequentially into the channel for this proposed MAC protocol and both the DA and the SB technologies are utilized to enhance the system throughput. The analytical formulation of the proposed MAC protocol is derived in detail. The numerical results, using the closed-form formulation and the computer simulations, show that the peak throughput of the proposed MAC protocol is up to 90% exceeding that of a Pure Aloha (PA) MAC protocol with the DA and the SB technologies.