Research On Scheduling Algorithm Of Joint Routing In Backhaul Network

In order to cope with the explosive growth of the future mobile communications network traffic,a large number of cell base stations will be deployed.but it will also bring a significant challenge to the backhaul network.And with the huge bandwidth available in the millimeter wave(mmWave)band,the wireless backhaul at mmWave frequencies can be a promising backhaul solution for 5G small cells.Due to the high propagation loss of millimeter wave links and the dense deployment of cells,the routing and link scheduling of backhaul networks has become a research hotspot.In this paper,we take the ultra dense network millimeter wave wireless backhaul as the research background,it mainly studies the link scheduling algorithm of the backhaul network,and uses the result of route calculation as the input of the link scheduling algorithm to achieve joint optimization.The Greedy Coloring(GC)algorithm is a classic frame-based scheduling algorithm in wireless networks..On the basis of the in-depth study of the scheduling algorithm and the improved algorithm,this paper improves it.The main work is as follows:1.A new link scheduling algorithm based on maximum transmission set is proposed to solve the problem that GC algorithm is not updated timely,time slot is wasted,and interference model is not set up properly.By introducing the interference conflict graph to identify the interference information in the backhaul network,and based on this,we add the maximum transmission set search algorithm to get the largest transmission set that can be transmitted at the same time.According to the largest transmission set searched,in the design scheduling and time slot allocation algorithm,the slot allocation principle of GC algorithm is changed.The minimum link demand slot is allocated as the current scheduling time to the current transmission set,and at the same time,the update mechanism of the scheduling set is added.The simulation results show that,compared with the GC algorithm,the proposed algorithm has a better performance in reducing the transmission delay and improving the throughput despite the long execution time.2.The improved algorithm ignores the loss of message and "throughput falsehood",such as the transmission service quality(QoS).Based on the design idea of the improved algorithm,the link scheduling algorithm based on the maximum QoS transmission set is proposed.The number of links that satisfy the QoS is guaranteed by defining the routing target as the sum of the QoS quality in the maximum network.In the search algorithm,the QoS priority value is defined,and the maximum QoS transmission set is searched with the node degree.Then,the number of links to maximize the number of QoS is achieved in the scheduling and slot allocation algorithm.The simulation results show that the proposed algorithm can increase the number of successful scheduling links and improve the throughput performance of the network within the allowable range of overhead.