A Resource Allocation Algorithm for Space-Air-Ground Integrated Network Based on Deep Reinforcement Learning
The Space-Air-Ground Integrated Network(SAGIN)can effectively meet the communication needs of various service types by improving the resource utilization of the ground network,but ignoring the adaptive ability and robustness of the system and the Quality of Service(QoS)in different users.In response to this problem,a Deep Reinforcement Learning(DRL)Resource allocation algorithm for urban and suburban communications under the SAGIN architecture is proposed in this paper.Based on Reference Signal Reception Power(RSRP)defined in the 3rd Generation Partnership Project(3GPP)standard,considering ground co-frequency interference,and using the time-frequency resources of base stations in different domains as constraints,an optimization problem to maxmize the downlink throughput of system users is constructed.When using the Deep Q-network(DQN)algorithm to solve the optimization problem,a reward function which can comprehensively consider the user's QoS requirements,system adaptability and system robustness is defined.Considering the service requirements of unmanned vehicles,immersive services and ordinary mobile communication services,the simulation results show that the value of the reward function which represents the performance of the system is increased by 39.1%compared with the greedy algorithm under 2 000 iterations.For the unmanned vehicle services,the average packet loss rate by the DQN algorithm is 38.07%lower than that by the greedy algorithm,and the delay by the DQN algorithm is also 6.05%lower than that by the greedy algorithm.