高铁环境下基于QoS用户业务的公平性功率分配算法

鉴于高速铁路(HSRs)通信业务的多样性,侧重于单一类型业务的传输优化方案,已无法满足用户业务服务质量(QoS)差异性显著提升的需求。针对HSRs通信环境,将用户业务分为时延敏感业务和时延非敏感业务,以满足用户QoS需求且同时兼顾占用无线信道的公平性为优化目标,研究了基站(eNB)平均发射功率约束条件下的功率分配问题。根据eNB能否预先获知用户的期望速率,分别采用了基于用户期望和基于预分配的功率分配策略。仿真结果表明,ε-Optimal比例公平算法的eNB发射功率较高且用户满意度较低;信道反演算法只针对时延敏感用户能较好地满足其QoS(最大耐受时延映射的期望速率),并且固定功率分配算法仅能够满足时延非敏感用户的QoS,两种算法均无法保证用户间的公平性;所提算法既具有较高的用户满足度,又较好地保证了用户间的公平性。

Power Control Algorithm Based on Fairness and QoS in High-speed Railway Scenarios

With the diversity of high-speed railways communication services,the transmission optimization strategy focusing on a single type of service has been unable to meet the needs of significant difference in user service quality(QoS).In this paper,the user service information flow was divided into time delay-sensitive stream and time delay-insensitive stream in HSRs scenario.To meet the users’QoS requirements and the fairness of wireless channel occupying,the power allocation problem under the average eNB transmission power constraints was studied.According to whether eNB knew the user expected rate in advance,the user-expectation based and the pre-allocation based power allocation strategies were adopted respectively.The simulation results show that theε-Optimal proportional fair algorithm has higher eNB transmission power and lower user satisfaction.The channel inversion algorithm and fixed power allocation algorithm can satisfy the delay-sensitive users’QoS(i.e.,the expected rate mapped by tolerance delay)and delay-insensitive users’QoS,respectively.Neither algorithm can guarantee the fairness among users.The proposed algorithm has higher user satisfaction and better fairness among users.