Research On Joint Allocation Strategy Of Communication And Cache Resources In Wireless Networks

In the future(The 6th generation mobile communication,6G)network,the data traffic generated by emerging network services and applications shows an explosive growth trend,which brings great pressure to the wireless communication network.Deploying cache resources in wireless network devices is considered to be an important way to reduce backhaul link load,network transmission delay and content redundancy transmission,and has been widely concerned and recognized by academia and industry.In addition,in order to meet the requirements of 6G networks such as larger information capacity,higher transmission rate,and lower transmission delay,wireless communication networks are developing in the direction of densification.With the increase,the interference in the wireless communication network is also more complex,and the efficient interference management technology is very important.Interference alignment(IA)technology,as an efficient interference management technology,can manage the interference in the network.However,interference alignment technology often needs to obtain perfect channel state information at the transmitter(CSIT),which is difficult to achieve in reality.The topological interference management(TIM)technology based on topology information has been widely studied because it only uses topology information for interference management and can avoid CSIT feedback.Therefore,this thesis studies the joint allocation strategy of wireless network communication and cache resources based on topology interference management.Firstly,this thesis proposes a cache-assisted topology interference management scheme for partially connected multiple input multiple output(MIMO)interference channel(IC)networks,which eliminates the interference in the network,which improves the degree of freedom(DoF)of the network and avoids the CSIT feedback overhead of the network.Specifically,the receivers uses the locally cached message to eliminate part of the interference signal in the received signal,and obtains an equivalent part of the connection network after eliminating the part of the interference.Then,the precoding vector and decoding vector of single input single output(SISO)network with the same topology as the equivalent part of the connected network are solved by using the topology interference management scheme based on maximum topology matrix(MTM).Finally,the topological interference management scheme of MIMO wireless network is designed by using the precoding vector and decoding vector of the SISO network to eliminate the remaining interference.The simulation results show that the cache-assisted topology interference management scheme proposed in this thesis can effectively improve the DoF of the network in most scenarios.Secondly,for the wireless communication network based on topology information,this thesis proposes a joint allocation scheme of wireless network communication and cache resources based on topology interference management,which improves the degree of network freedom,reduces the transmission delay,and avoids the CSIT feedback overhead of the network.Specifically,using the topology connection information of the network,the transmitters and the receivers are jointly used to allocate cache resources,and the cache resources of the transmitters are encoded with XOR coding.Then,the MIMO wireless network with allocated cache resources is transformed into a partially connected MIMO IC network,and the prediction of the SISO IC network with the same topology as the partially connected MIMO IC network is solved by a topology interference management scheme based on a maximal topology matrix.The precoding vector and decoding vector are then used to design the MIMO topology interference management scheme based on the precoding vector and decoding vector to eliminate the interference in the network.Compared with the joint allocation of wireless network communication and cache resources based on asymptotic interference alignment,the scheme proposed in this thesis can eliminate the interference in the network under limited time slot,and the simulation analysis shows that the performance of the scheme proposed in this thesis is close to the joint allocation scheme of wireless network communication and cache resources based on asymptotic interference alignment.