一种带内全双工无线网络MAC机制及性能分析

Medium access control mechanism and performance analysis for in band full duplex wireless networks

在带内全双工无线接入点与半双工用户的无线网络中,当接入点发起信道接入请求时,数据传输阶段接入点的同频上行链路将处于空闲状态,此时网络吞吐量仅相当于半双工模式.针对上述问题,提出一种新的媒体接入控制机制,可通过一次信道接入建立非对称带内全双工双向链路.无论接入点还是用户接入信道,该机制均能够保证接入点与两个用户进行同时同频上下行数据传输,提高了网络吞吐量.通过构建Markov模型分析非对称带内全双工-媒体接入控制的吞吐量性能.结果表明,非对称带内全双工-媒体接入控制与请求发送/允许发送机制相比,吞吐量提高了近1倍.

This paper considers an in-band full-duplex wireless network that consists of an AP with full-duplex capability and miultiplc clients without full-duplex capability. When AP initiates a channel access request, the uplink of theAP is in the idle state in the data transmissionnetwork throughput. Therefore, a new MAC mechanism called Asymmetrical Full Dupiex （AFD） is proposed, which can establish an asymmetric IBFD bidirectional link through primary channel access. No matter what node wins the channel, the mechanism can ensure that the uplink flow and the downlink flow of the AP communicate simultaneously at the same frequency. In this way, the throughput of the wireless network is greatly improved. Both analysis and numerical simulations are carried out to evaluate the performance of the proposed MAC mechanism. The results show that the throughput of theAFD-MAC is nearly doubled compared with the RTS/CTS mechanism.