OFDM中继系统中保证混合业务QoS的研究

QoS Guarantee for Mixed-Service in OFDM Relay System

为保证正交频分复用中继系统中混合业务的QoS要求,提出相对最长队列优先/相对比例公平的调度算法R-LQAF/RPF.根据实时用户的速率需求引入相对变化函数,并利用RPF算法提高实时业务用户的吞吐量.同时根据用户队列长度和系统队列长的关系,采用R-LQAF算法降低用户丢包率,保证了非实时用户的QoS满意度.仿真结果表明,与比例公平和最大加权时延优先算法相比较,R-LQAF/RPF算法不仅能针对不同业务采取不同的调度策略,而且对用户吞吐量、速率需求满意度、丢包率性能均有所提升,充分保证了混合业务的QoS要求.

To ensure QoS requirements for mixed-service in an orthogonal frequency division multiplexing relay system, we propose a relative largest queue aware first/relative proportional fair （R-LQAF/RPF） scheduling algorithm. By setting a relative variation function, we use an RPF scheduling algorithm to enhance the realtime user throughput to meet the actual user rate requirements. We also use an R-LQAF scheduling algorithm to improve the scheduling performance, decrease the packet loss rate, and ensure QoS requirements for non-realtime user according to the relationship of the user queue length and the system queue length. Simulation results show that, compared with the existing proportional fair and the largest weighted delay first algorithm, the R-LQAF/RPF algorithm can flexibly businesses, effectively improve user performances in terms demanded rate, and guarantee QoS requirements of mixed choose different scheduling strategies for different of throughput, packet loss rate, and satisfaction of businesses.