基于OFDMA面向QoS保障的新型多址接入协议

摘要

下一代无线局域网(wireless local area network,WLAN)IEEE 802.11ax标准委员会将高服务质量(quality of service,QoS)保障作为下一代WLAN的重要技术目标之一.由于无线业务种类繁多,因此对QoS的要求必然也是多种多样,然而现有的基于正交频分多址(orthogonal frequency division mul-tiple access,OFDMA)的介质访问控制(media access control,MAC)协议均不能很好地支持QoS多样化且要求高的特点.针对这一问题,提出了一种面向QoS的下一代WLAN OFDMA多址接入协议.在该协议中,一方面考虑后向兼容性,沿用IEEE 802.11e的4种优先级业务;另一方面引入面向QoS的优先级调度算法以支持未来无线业务QoS多样化且要求高的特点.最后,通过仿真验证所提协议QoS-OFDMA MAC的系统有效吞吐量比顺序调度算法的 OFDMA MAC 和比例公平调度算法的OFDMA MAC分别提高了57.8%和59%.%The next generation wireless local area network ( WLAN) 802.11ax standards committee takes high qual-ity of service( QoS) guarantee as one of important technology goals of the next generation WLAN. As a result of a variety of wireless traffics, so the requirements of the QoS must also be varied. However, the existing media access control( MAC) protocol based on orthogonal frequency division multiple access( OFDMA) can't support QoS diver-sification and high requirement well. To solve this problem, this paper presents a QoS-oriented OFDMA MAC for the next generation WLAN. On one hand, for backward compatibility consideration, continue to use four priority traffics of 802.11e in this protocol; on the other hand,the introduction of QoS-oriented priority scheduling algorithm to support future wireless traffic feature which is QoS of diversification and high requirements. Finally, through the simulation, the system effective throughput of the proposed QoS-OFDMA MAC is 57.8% and 59% higher than the OFDMA MAC of the sequential scheduling algorithm and the OFDMA MAC of the proportional fairness algorithm.