Considering that weak channel collision detection ability, long propagation delay and heavy load in LEO satellite communications, a valid adaptive APRMA MAC protocol was proposed. Different access probability function...Considering that weak channel collision detection ability, long propagation delay and heavy load in LEO satellite communications, a valid adaptive APRMA MAC protocol was proposed. Different access probability functions for different services were obtained and appropriate access probabilities for voice and data users were updated slot by slot based on the estimation of the voice traffic and the channel status. In the proposed MAC protocol limited wireless resource is allocated reasonably by multiple users and high capacity was achieved. Three performance parameters: voice packet loss probability, average delay of data packets and throughput of data packets were considered in simulation. Finally simulation results demonstrated that the performance of system was improved by the APRMA compared with the conventional PRMA, with an acceptable trade-off between QoS of voice and delay of data.展开更多
Packet Reservation technology is frequently used in Media Access Control protocols. To increase the utilization of bandwidth, D.J. Goodman et al. presented the p-persistent algorithm, in which an access probability p ...Packet Reservation technology is frequently used in Media Access Control protocols. To increase the utilization of bandwidth, D.J. Goodman et al. presented the p-persistent algorithm, in which an access probability p is used to reduce collision. This idea is applied in many protocols. In this paper, the distribution of the number of accessing terminals is forecasted to determine the access probability dynamically. This method helps the protocol adaptive to various system environments automatically.展开更多
文摘Considering that weak channel collision detection ability, long propagation delay and heavy load in LEO satellite communications, a valid adaptive APRMA MAC protocol was proposed. Different access probability functions for different services were obtained and appropriate access probabilities for voice and data users were updated slot by slot based on the estimation of the voice traffic and the channel status. In the proposed MAC protocol limited wireless resource is allocated reasonably by multiple users and high capacity was achieved. Three performance parameters: voice packet loss probability, average delay of data packets and throughput of data packets were considered in simulation. Finally simulation results demonstrated that the performance of system was improved by the APRMA compared with the conventional PRMA, with an acceptable trade-off between QoS of voice and delay of data.
文摘Packet Reservation technology is frequently used in Media Access Control protocols. To increase the utilization of bandwidth, D.J. Goodman et al. presented the p-persistent algorithm, in which an access probability p is used to reduce collision. This idea is applied in many protocols. In this paper, the distribution of the number of accessing terminals is forecasted to determine the access probability dynamically. This method helps the protocol adaptive to various system environments automatically.
