张刚 胡恒 陈婉
摘 要: 由于车车通信(V2V)在基于终端直通技术(D2D)实现时对可靠性和时延要求更加严格,D2D的无线资源分配需要重新设计,因此,对一种基于竞争的资源池资源分配方式进行讨论和改进。设计了一种在授权频段下的信道检测机制,通过对不同检测窗口的设计与分析,实现了车载终端(V?UE)通过信道检测,尽可能避免在选择资源池资源时发生资源碰撞导致信道质量下降。同时通过对时延要求不同的业务设定不同窗口,实现了对信道资源不同优先级的占用。通过系统级仿真,证明了该机制在提高信道质量的同时,能够实现对不同业务占用信道的时延差异。
关键词: V2V; 资源分配; 资源池; 信道檢测机制; 资源碰撞; 时延
中图分类号: TN929.5?34 文献标识码: A 文章编号: 1004?373X(2018)07?0140?07
Design and optimization for channel detection mechanism
of resource pool in LTE?V2V
ZHANG Gang, HU Heng, CHEN Wan
(School of Communication and Information Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, China)
Abstract: Since the vehicle?to?vehicle (V2V) communication based on device?to?device (D2D) communication technology has higher requirement for reliability and time delay, it is necessary to redesign the wireless resource allocation of D2D. A resource allocation mode based on competition is discussed and improved. A channel detection mechanism at authorized frequency band was designed. The different detection windows are designed and analyzed to realize the channel detection of vehicle?user equipment (V?UE), and avoid the channel quality reduction caused by resource collision when the resource is selected in resource pool. The different windows are set for the time delay requirement according to different services to occupy the channel resource with different priorities. The result of system?level simulation shows that the mechanism can realize the time delay diffe?rence for channel occupation in different services while improving the channel quality.
Keywords: V2V; resource allocation; resource pool; channel detection mechanism; resource collision; time delay
0 引 言
V2V(Vehicle?to?Vehicle,V2V)通信被认为是实现智慧交通系统的重要技术,其优势在于能够提高车辆行驶安全性和交通效率,减小能量消耗,支持智能交通系统的新业务等[1]。然而实现V2V通信对时延和可靠性提出了更高的要求[2?5]。因此,3GPP立项研究车联网(Vehicle?to?Everything,V2X)标准化,并分别对车车通信、车路通信(Vehicle?to?Infrastructure,V2I)、车人通信(Vehicle?to?Pedestrian,V2P)进行标准制定。根据3GPP目前达成的共识,V2V技术将基于D2D(Device?to?Device,D2D)技术实现,并输出标准报告TR36.885[6]。在文献[6]中提出,为了满足V2V的时延和可靠性,需要对V2V的调度方式和资源分配进行重新设计。本文就对目前资源分配方式进行了研究并做出改进。
1 相关工作
目前,已有一些文献研究基于D2D的V2V的调度问题和资源分配方式。由于V2V的一个重要……