Research On Radio Resource Management In Dense Cell Networks

Dense wireless network is the typical architecture of the fifth generation mobile communication system (5G). Network densification makes the interference issues more complex. With the increasing number of mo-bile equipments in vehicles, the problems about how to enhance the quality of communication in transportation system as well as how to improve user satisfaction, mainly focusing on rate, delay and stability aspect, have received much concern. Dense wireless network needs efficient RRM (Radio Resource Management, RRM) technology to dynamically control and manage radio resources. It can solve the complex problems of inter-ference and improve system throughput. This thesis focuses on the research of radio resource management in dense network. To optimize the system performance of dense network, the thesis studies the resource schedul-ing, power control and power allocation respectively. The main research contents and research results include the following aspects:Firstly, based on the coexistence scenario of vehicles users and general users in mobile communication network, the thesis, with the consideration about the number of active mobile users in vehicles, improves al-gorithms about Proportional Fairness (PF) and Modified Largest Weighted Delay First (M-LWDF) algorithm , and also proposes a resource scheduling algorithm based on the delay utility function. These methods aim to enhance the quality of the mobile communication network, while effectively balance system throughput and user fairness. The simulations study the performance of the improved PF, M-LWDF and the resource scheduling algorithm based on the delay utility function. The results show that the resource scheduling algo-rithm based on the delay utility function balances the system capacity and user fairness. And the improved PF and M-LWDF algorithm have a better performance about system throughput, which is close to the resource scheduling algorithm based on the delay utility function.Secondly, referring to downlink power control schemes defined in 3GPP and considering the dense net-work scenarios, the thesis proposes a power control mechanism based on priority grouping,which protects the macro users and guarantee the minimum requirements of users'data rate in small cell. The study shows that the mechanism can further reduce the transmit power of small cell base station with a lower outage prob-ability.And also the mechanism reduces interference between base stations and improves the communication quality of users in system.Finally, the thesis proposes an adaptive power allocation algorithm based on users'fairness and simpli-fies the solving process. Considering users'minimum SINR requirements and constraint about the maximum transmit power of small cell, the algorithm aims to maximize the small cell system capacity. The research shows that the proposed algorithm guarantees the fairness of users and reduces the outage probability at the expense of little amount of system throughput.