Optimization Of Wireless Resources In LTE-A Heterogeneous Network

With the development of communication technologies and the increase in the types of services,the demand of data rates has grown exponentially.The traditional single-layer network architecture has been unable to meet the traffic flow requirements.The heterogeneous network technology introduced by Long Term Evolution-Advanced(LTE-A)can effectively reduce the cost of network construction and maintenance and improve the spectrum efficiency of the system.However,with the increase of the number of base stations and users in the LTE-A heterogeneous network,the complex interference existing between the macro base station(MBS)and the small base station(SBS)reduces the communication quality of the users.The dense deployment of small base stations also greatly increases the power consumption of the system.In the context of LTE-A heterogeneous networks,a corresponding optimized strategy for the main problems is proposed in the current network and the main contents are as follows:For the problem that the increase of the number of small base stations in LTE-A heterogeneous networks leads to a large-scale increase of power consumption in the system,an optimized clustering-based sleep strategy is proposed.In this optimized strategy,the clustering algorithm is firstly used to group the small base stations in the system and the small base stations with large interference can be grouped into the same cluster.Then,the optimized problem regarding user satisfaction and power consumption is established for the small base stations in each cluster,and the sleeping algorithm is used to determine the operating status of the small base stations in the network.The optimized strategy can effectively reduce the power consumption existing in the heterogeneous network while mitigating the system interference and improving the service quality of the users.In addition,the outage probability of the system is improved by clustering the small base stations.From the evaluation of simulation,the power consumption of the optimized strategy is reduced by 14.7%and 6.7% respectively compared with the no-sleep strategy and the traditional sleep strategy.At the same time,the optimized strategy helps to reduce the outage probability of the overall system.In addition,aiming at the problem of load imbalance and system interference in LTE-A heterogeneous networks,an energy efficient optimization strategy based on Enhanced Inter-Cell Interference Coordination(eICIC)technology is proposed.This optimized strategy allocates the sub-frames and resource blocks of the macro base stations in the time domain and frequency domain respectively.The optimization of the energy efficiency of the system is established by taking into account the connection between the users and base stations,Almost Blank Sub-frame(ABS)ratio,resource allocation in the frequency domain,and the power transmission of the macro base station.The optimized problem is solved iteratively with the Gauss-Seidel method.Simulation results show that compared with Maximum Reference Signal Received Power(MAX-RSRP)strategy and Low Power Almost Blank Sub-frame(LP-ABS)strategy,this optimized strategy not only improves user satisfaction,but also increases the energy efficiency of the system by 24.2% and19.1%.Furthermore,the proposed strategy increases the user fairness by 33.8% and23.4%.