基於感知半持續資源排程的資源排除及選擇窗口的演算法以降低碰撞機率

Reducing Collision Probability with Resource Preclusion and Selection Window Adjustment for Sensing-Based SPS Algorithm

林杰甫(Chieh-Fu Lin)

指導教授 ： 李程輝

國立交通大學/電機學院/電信工程系所/碩士(2020年)

摘要

第三代合作夥伴計畫定義了基於感知半持續資源排程演算法，作為車聯網側鏈通信中分散式資源選擇的標準，在資源選擇前進行偵測可以大大降低封包碰撞的可能性，然而，我們發現如果使用者裝置使用不同的資源預留間隔，封包碰撞機率則會變相當大。在我們論文提出一種機制來防止碰撞，所提出的方法僅需簡單的計算，且不需在側鏈控制信息中附加訊息。對於我們的模擬場景，在理想的通道條件下，碰撞機率可以降低77%以上。當考慮通道條件下，封包接收率最高可以提升6.4%。此外，我們提出了另一種降低碰撞機率的機制，基本概念是讓使用者裝置縮小其選擇窗口，以避免選擇窗口重疊。當與我們先前提出的資源排除機制結合時，在理想的通道條件下，碰撞機率可以降低79.10%以上。當考慮通道條件下，封包接收率最高可以提升21.11%。

關鍵字

基於感知半持續資源排程 ； 車聯網 ； 側鏈路通信 ； 碰撞機率

並列摘要

Sensing-based semi-persistent scheduling algorithm was developed by 3GPP as the standard for distributed resource selection in V2X sidelink communications. Sensing before resource selection largely reduces collision probability. However, we found that considerable collisions can happen if user equipments use different resource reservation intervals. An enhancement is proposed in this thesis to prevent collisions. The proposed enhancement requires only simple computation and does not need additional information to be transmitted in sidelink control information. For our simulation scenario, the collision probability can be reduced by more than 77% under perfect channel condition. When channel condition is taken into consideration, the packet reception ratio can be improved by 6.4% at most. In addition, we propose another scheme to reduce collision probability. The basic idea is to let UEs shrink their selection windows to avoid overlapping of selection windows. When combined with a resource preclusion strategy we proposed previously, the collision probability can be reduced by more than 79.10% under perfect channel condition. When channel condition is taken into consideration, the packet reception ratio can be improved by 21.11% at most.

並列關鍵字

Sensing-based SPS ； V2X ； Sidelink communications ； Collision probability

參考文獻

[1] 3GPP TR 38.885, v16.0.0, “Study on NR Vehicle-to-Everything (V2X)”, Mar. 2019.

[2] A. Bazzi, B. M. Masini, A. Zanella, and I. Thibault, “On the performance of IEEE 802.11p and LTE-V2V for the cooperative awareness of connected vehicles,” IEEE Trans. Veh. Technol., vol. 66, no. 11, pp. 10419–10432, Nov. 2017.

[3] B. Di, L. Song, Y. Li, and G. Y. Li, “Non-orthogonal multiple access for high-reliable and low-latency V2X communications in 5G systems,” IEEE J. Sel. Areas Commun., vol. 35, no. 10, pp. 2383–2397, Oct. 2017.

[4] X. Zhang, Y. Shang, X. Li, and J. Fang, “Research on overlay D2D resource scheduling algorithms for V2V broadcast service,” IEEE VTC, pp. 1–5, Sept. 2016.

[5] G. Cecchini, A. Bazzi, B. M. Masini, and A. Zanella, “LTEV2Vsim: An LTE-V2V simulator for the investigation of resource allocation for cooperative awareness,” IEEE Conf. Models Technol. ITS, pp. 80–85, Jun. 2017.