CAJ | 학술논문

与传统无线传输相比，虽然协作中继节点的参与可以大大提高无线网络性能，然而协作中继会带来严重的信道竞争问题，这给协作通信环境中的信道访问控制带来挑战。为了解决这个问题，提出一种RTS/CTS（Request To Send/Clear To Send）与忙音结合的MAC（media access control）信道接入方案。该方案使用3个忙音来标识信道的使用状态，并解决协作通信中的隐藏终端和暴露终端问题。基于忙音信号，还提出了一种带宽节俭的协作节点选择算法。通过侦听忙音信号，源节点可分布式地选择最优的协作节点。理论分析和仿真实验表明所提方案能有效地提高协作通信中的信道利用率，很好地解决了协作通信中的隐藏终端暴露终端问题。在数据包大小超过3500 B时，本协议中暴露终端受传输节点阻塞的时间不到整个传输时间的10％。
여전통무선전수상비，수연협작중계절점적삼여가이대대제고무선망락성능，연이협작중계회대래엄중적신도경쟁문제，저급협작통신배경중적신도방문공제대래도전。위료해결저개문제，제출일충RTS/CTS（Request To Send/Clear To Send）여망음결합적MAC（media access control）신도접입방안。해방안사용3개망음래표식신도적사용상태，병해결협작통신중적은장종단화폭로종단문제。기우망음신호，환제출료일충대관절검적협작절점선택산법。통과정은망음신호，원절점가분포식지선택최우적협작절점。이론분석화방진실험표명소제방안능유효지제고협작통신중적신도이용솔，흔호지해결료협작통신중적은장종단폭로종단문제。재수거포대소초과3500 B시，본협의중폭로종단수전수절점조새적시간불도정개전수시간적10％。
Compared with traditional wireless communication , although relay nodes in cooperative communication can help to increase the performance of a wireless network,relay nodes may cause the serious competition for wire-less channel accessing ,which makes the channel access problem in cooperative communication challenging .To solve the problem,a novel MAC ( media access control) scheme by concurrently considering RTS/CTS ( Request To Send/Clear To Send) and busy tone is proposed in the paper.In the scheme,three busy tones are proposed to iden-tify the state of channel occupation and solve the hidden terminal and exposed terminal problems in cooperative communication.Based on the busy tone,this paper also proposes a bandwidth efficient relay selection algorithm.The source can choose the best relay in a distributed way by sensing the busy tone .The theory and simulation results demonstrate that the proposed scheme can efficiently improve the channel utilization and solve the hidden terminal and exposed terminal problems in cooperative communication .The blocking time ratio of the proposed MAC scheme is less than 10% when the data packet size surpasses 3500B.