Research On Admission Control And Resource Allocation Algorithm For Terahertz Communication Systems

With the rapid development of the Internet and mobile communication technologies,people’s demand for high-speed wireless communication is increasing,and new applications with higher bandwidth requirements are also emerging.Therefore,spectrum resources with higher bandwidth need to be explored urgently to develop a new generation of ultra-high-speed transmission wireless communication technology.Terahertz(THz)communication has become one of the most promising technologies in the sixth generation mobile communication network(6G)due to its huge bandwidth and ultra-high data transmission rate.Radio resource management has always been an important part of wireless communication systems,which has a significant impact on the performance of communication systems.Therefore,it is very important to study resource management algorithms in Terahertz communication.Resource allocation and access control in indoor Terahertz communication systems are studied.The main research contents are as follows:1)In the indoor terahertz communication scenario,a resource allocation algorithm based on spectral characteristics is proposed with the goal of maximizing the system spectral efficiency.Firstly,the resource allocation problem is modeled as a non-convex optimization problem,and then the optimization problem is decomposed into sub-channel allocation and power allocation sub-problems and solved iteratively.Regarding the sub-channel allocation problem,in view of the window characteristics and high path-loss characteristics of the Terahertz spectrum,based on the principle of Long-User-Central-Window(LUCW),the problem is transformed into a bipartite graph matching problem and finally be solved using the improved Hungarian algorithm.And the power allocation problem is solved iteratively using the Sequential Quadratic Programming(SQP)algorithm.The simulation results show that the proposed algorithm can achieve higher system spectral efficiency than conventional algorithms.2)As to the Terahertz communication system based on Massive Multiple Input Multiple Output(Massive MIMO),a resource allocation algorithm based on hybrid beamforming is proposed.First,the users are grouped based on the channel correlation,and the access control is performed on the users according to the minimum rate requirements,so as to select the appropriate users to access the system.Next,the resource allocation problem in this scenario is decomposed into four sub-problems,including hybrid beamforming,sub-channel allocation,power allocation and sub-array allocation,and the corresponding algorithms for each sub-problem are given to find suboptimal solution iteratively.For hybrid beamforming,the genetic algorithm is used to maximize the sum of the normalized channel gains over all sub-channels within each user group.For sub-channel allocation,since the same bandwidth is multiplexed between different groups,orthogonal sub-channels are allocated to users of each group by genetic algorithm.The power allocation is solved iteratively within each group using the SQP algorithm.For sub-array allocation,a greedy algorithm is used to sequentially allocate sub-arrays to the user group with the largest increase in the total transmission rate.The simulation results show that the resource allocation scheme can improve the spectral efficiency of the system.The simulation results show that the proposed resource allocation algorithm can improve the spectral efficiency of the system,and also has good performance when the number of users is large.