| The design of distributed algorithms in wireless networks is complicated because not only the problem itself but also the interference and channel conflicts in the wireless network are considered.The absMAC layer provides reliable local broadcast communication.Such that high-level algorithms can be designed in terms of these functions,independent of specific channel behavior.Because the global interference of the physical interference model makes the distributed algorithm difficult to be analyzed.The absMAC layer algorithm is mostly based on the graph interference model.At present,the only algorithm based on the physical interference model is implemented by the approximation method.How to exact implement the absMAC layer under the physical interference model has not been solved.Based on this situation,a general local broadcast algorithm using physical carrier sensor is proposed.Global interference makes it very difficult to judge whether a node broadcast successfully.Through the carrier sensor,the node can judge the situation according to the interference and the received message,so that the sending node can stop in time.The node has a large transmit power.The node that broadcasts can cover a larger range than the neighbor,causing some of the surrounding nodes to stop transmitting,thereby speeding up local broadcast.The algorithm shows that the delay function is asymptotically optimal.The simulation results show that the algorithm reduces the broadcast delay by around 10 times,compared with the approximation algorithm.The general local broadcast problem considers the number of distinct messages for the first time,and proves that the complexity of local broadcast is related to the number of distinct messages.The general local algorithm is potentially useful for solving data aggregation and collection.The asymptotically optimal results of the absMAC layer delay function lay the foundation for many new and faster high-level algorithms. |
PDF Full Text Request