Performance evaluation of multiple access techniques in land mobile satellite networks

The performances of four different multiple-access techniques for land-mobile satellite networks are compared. These multiple-access techniques are: slotted ALOHA, slow frequency-hopping and two reservation schemes. A hybrid automatic-repeat-request (ARQ) scheme based on Reed-Solomon codes is used to combat the error bursts resulting from multipath fading and shadowing. The advantages of using symbol interleaving and erasure decoding are demonstrated. The effect of such parameters as the rate of the forward error correction code, the guard time, and the error rate on the acknowledgment channel is evaluated