通過在行動網路中使用 Orthogonal Frequency Division Multiple Access (OFDMA) 技術，在行動網路上使用廣播和多播的 1 對 n 影片串流，在 3GPP 中被稱為演進的多媒體廣播多播服務 (eMBMS)，成為可行的。將 eMBMS 用於 1 對n 影片串流的關鍵問題是，它需要為分配給 eMBMS 多媒體服務的 n 個服務範圍內的移動車輛的所有資源塊 (RB) 選擇統一的編碼方案 (MCS)。3GPP 定義了Single Cell Point To Multiploint (SC-PTM)，考慮到 eMBMS 的多媒體服務中涉及的所有 n 個移動車輛，這些車輛位於行動網路的小區中，以具有統一的 MCS。
由於在一個 eMBMS 的多媒體服務中涉及的所有 n 個移動車輛都有不同的信道質量指標 (CQI)，這導致不同的 RB 的 MCS 不同，並且需要同時為 k 個 eMBMS的多媒體服務提供服務，無線電資源分配問題擁有 eMBMS 變得非常複雜，優化的無線資源分配是一個 NP 問題，而所提出的分組方法可以有效解決此問題。
分組方法的思想是將具有相似 CQI 的 VU 分組在一起，並為每組 VU 分配一組專用的 RB。這樣，CQI 較好的 VU 的影片質量就不會被 CQI 較差的 VU 拖累。
然而，如何進行分組，即，哪些 VU 應該分組在一起，應該有多少組以及如何為每個組分配 RB 是需要解決的主要技術問題。此計畫提出了使用基於標準差的分組及兩階段的資源分配方法 (2SRA-SDG)，以便在 SC-PTM 環境中使用分組方法來做資源分配。所提出的 2SRA-SDG 方法的兩個階段是 (1) 為每個多媒體服務找到適當的分組配置和 (2) 為每個多媒體服務分配適當的 RB。在第一階段，分組的配置會以每個組中包含的 VU 的 CQI 的標準差做為考量，然後，根據建議的資源分配方案，為每個組配置分配一些資源。通過嘗試每個多媒體服務的不同分組配置，可以計算出每個分組配置的效能。然後，使用該效能結果來決定哪個分組配置最適合各個多媒體服務。在第二階段，在為每個多媒體服務找到合適的分組配置後，2SRA-SDG 使用建議的資源分配方案為每個組分配合適的 RB，完成資源分配。性能評估結果表明，所提出的 2SRA-SDG 方法可以（1）使 RB 具有比其他方法更高的無線電資源效率，（2）為 VU 分配適當的影片品質，而具有更好 CQI 的 VU 不會被具有較差 CQI 的 VU 拖累以實現公平性，並且 (3) 擁有更多的 VU 以獲得比其他方法更好的影片品質。

Through the use of the Orthogonal Frequency Division Multiple Access (OFDMA) technology in cellular network, 1-to-n video streaming using broadcast and multicast over the cellular network, which is named as evolved Multimedia Broadcast Multicast Services (eMBMS) in 3GPP, becomes feasible. The key issue of having eMBMS for 1-to-n video streaming is that it needs to select a unified Modulation and Coding Scheme (MCS) for all of the Resource Blocks (RBs) allocated to the n involved moving vehicles of an eMBMS’s multimedia service. 3GPP defined Single Cell Point To Multiploint (SC-PTM) considering all of the n involved moving vehicles, which are in a cellular network’s cell, of an eMBMS’s multimedia service to have a unified MCS. Since all of the n involved moving vehicles in an eMBMS’s multimedia service have different Channel Quality Indicators (CQIs), which result in different MCSs, for different RBs and it needs to serve k eMBMS’s multimedia services at the same time, the radio resource allocation problem for having eMBMS becomes very complicated, for which the optimized radio resource allocation is an NP-problem. A grouping approach can be adopted for resolving this problem. The idea of the grouping approach is to group the VUs with similar CQIs together and a dedicated set of RBs are allocated to each group of VUs. In this way, the video streaming quality of the VUs with the better CQIs won't be dragged by the VUs with the worse CQIs. Nevertheless, how to do the grouping, i.e., which VUs should be grouping together, how many groups it should have and how to allocate RBs to each group are the main technical issues to be resolved. This work proposed the Two-Stage-based Resource Allocation using the Standard Derivationoriented Grouping (2SRA-SDG) method for having eMBMS in the SC-PTM environment using the grouping approach. Two stages of the proposed 2SRA-SDG method are (1) finding the proper group configuration for each multimedia service and (2) allocating proper RBs to each of the multimedia services. In the first stage, the configuring of groups is based on the standard derivation of the CQIs of the contained VUs in each group. Then, each group configuration is allocated some resource based on the proposed resource allocation scheme. Through the tracing of different group configurations for each multimedia service, it can calculate the utility of each group configuration. Then, it uses the utility to determine which group configuration is the most suitable one for each multimedia service. In the second stage, after finding the proper group configuration for each multimedia service, it uses the proposed resource allocation scheme to allocate proper RBs to each group. The results of the performance evaluation shown that the proposed 2SRA-SDG method can (1) make the RBs have the higher spectrum efficiency than the other methods, (2) assign proper video quality to VUs and the VUs with the better CQIs won’t be dragged by the VUs with the worse CQI to achieve the fairness concern and (3) have more VUs to get the better video quality than the other methods.

[1] 3GPP TS 25.346, ”Introduction of the Multimedia Broadcast Multicast Service (MBMS) in the Radio Access Network (RAN); Stage 2 (Release 6)”, V6.13.0.
[2] ETSI, TS. "136 331 V9. 12.0 (2012-11)." LTE; Evolved Universal Terrestrial Radio Access (E-UTRA); radio resources Control (RRC); Protocol specification.
[3] J. Montalban et al., "Multimedia Multicast Services in 5G Networks: Subgrouping and Non-Orthogonal Multiple Access Techniques," IEEE Communications Magazine, VOL. 56, NO. 3, pp. 91-95, March 2018, doi: 10.1109/MCOM.2018.1700660.
[4] R. Kamran et al., "A Survey on Multicast Broadcast Services in 5G and Beyond," Proceedings of 2022 National Conference on Communications (NCC), 2022, pp. 344-349, doi: 10.1109/NCC55593.2022.9806729.
[5] C. Burdinat, T. Stockhammer, M. Raulet and T. Biatek, "Network Operator-Provided 5G Streaming Media and Future Broadcast Services," SMPTE Motion Imaging Journal, VOL. 131, NO. 6, pp. 10-16, July 2022, doi: 10.5594/JMI.2022.3175990.
[6] L. Richter and U. H. Reimers, "A 5G New Radio-Based Terrestrial Broadcast Mode: System Design and Field Trial," IEEE Transactions on Broadcasting, VOL. 68, NO. 2, pp. 475-486, June 2022, doi: 10.1109/TBC.2022.3154601.
[7] H. -H. Liu and H. -Y. Wei, "5G NR Multicast and Broadcast QoS Enhancement With Flexible Service Continuity Configuration," IEEE Transactions on Broadcasting, doi: 10.1109/TBC .2022 .3173173.
[8] X. Tan, S. Li, Y. Liu, Q. Zheng and D. Liu, "QoE-assured Live Video Streaming Based on Coalition Game in 5G eMBMS Networks," Proceedings of the 29th IEEE/ACM International Symposium on Quality of Service (IWQOS), 2021, pp. 1-6, doi: 10.1109/IWQOS52092.2021.9521296.
[9] H. Zhou, X. Wang, Z. Liu, Y. Ji and S. Yamada, "Resource Allocation for SVC Streaming Over Cooperative Vehicular Networks," IEEE Transactions on Vehicular Technology, VOL. 67, NO. 9, pp. 7924-7936, Sept. 2018, doi: 10.1109/TVT.2018.2847325.
[10] A. Alalewi, I. Dayoub and S. Cherkaoui, "On 5G-V2X Use Cases and Enabling Technologies: A Comprehensive Survey," IEEE Access, VOL. 9, pp. 107710-107737, 2021, doi: 10.1109/ACCESS.2021.3100472.
[11] Y. He et al., "D2D-V2X-SDN: Taxonomy and Architecture Towards 5G Mobile Communication System," IEEE Access, VOL. 9, pp. 155507-155525, 2021, doi: 10.1109/ACCESS.2021.3127041ETSI, TS. "136 443 V13. 3.0 (2016-05).
[12] P. Chau, Y. Lee, T.D. Bui, J. Shin, J. Jeong, “An Efficient Resource Allocation Scheme for Scalable Video Multicast in LTE-advanced Networks,” Proceedings of the 11th International Conference on Ubiquitous Information Management Communation (IMCOM 2017), pp. 1–8, 2017.
[13] A. De La Fuente, J. J. Escudero-Garzás and A. García-Armada, "Radio Resource Allocation for Multicast Services Based on Multiple Video Layers," IEEE Transactions on Broadcasting, VOL. 64, NO. 3, pp. 695-708, Sept. 2018, doi: 10.1109/TBC.2017.2781121.
[14] S. ul Zuhra, P. Chaporkar and A. Karandikar, "Auction Based Resource Allocation and Pricing for Heterogeneous User Demands in eMBMS," Proceedings of IEEE Wireless Communications and Networking Conference (WCNC 2019), pp. 1-6, 2019 doi: 10.1109/WCNC.2019.8885874.
[15] " LTE; Evolved Universal Terrestrial Radio Access Network (E-UTRAN); M2 Application Protocol (M2AP).
[16] ETSI TS 136 213, ”LTE; Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures (3GPP TS 36.213 version 12.3.0 Release 12)”, V12.3.0 (2014-10).
[17] Qin Mu, Liu Liu, Lan Chen and Yu Jiang, "CQI table design to support 256 QAM in small cell environment," Proceedings of the International Conference on Wireless Communications and Signal Processing, pp. 1-5, 2013 doi: 10.1109/WCSP.2013.6677171.
[18] T. Lee, W. Liu and A. C. -. Hsu, "An Efficient Multicast Scheme for Live Streaming Services in SC-PTM," Proceedings of the 90th IEEE Vehicular Technology Conference (VTC2019-Fall), pp. 1-5, 2019.
[19] S. U. Zuhra, P. Chaporkar and A. Karandikar, "Toward Optimal Grouping and Resource Allocation for Multicast Streaming in LTE," IEEE Transactions on Vehicular Technology, VOL. 68, NO. 12, pp. 12239-12255, Dec. 2019.
[20] J. Chen, M. Chiang, J. Erman, G. Li, K. K. Ramakrishnan and R. K. Sinha, "Fair and optimal resource allocation for LTE multicast (eMBMS): Group partitioning and dynamics," Proceedings of IEEE Conference on Computer Communications (INFOCOM 2015), pp. 1266-1274, 2015 doi: 10.1109/INFOCOM.2015.7218502.
[21] M. Condoluci, G. Araniti, A. Molinaro and A. Iera, "Multicast Resource Allocation Enhanced by Channel State Feedbacks for Multiple Scalable Video Coding Streams in LTE Networks," IEEE Transactions on Vehicular Technology, VOL. 65, NO. 5, pp. 2907-2921, May 2016.
[22] A. Khalid, A. H. Zahran and C. J. Sreenan, "RTOP: Optimal User Grouping and SFN Clustering for Multiple eMBMS Video Sessions," Proceedings of IEEE Conference on Computer Communications (INFOCOM 2019), 2019, pp. 433-441, doi: 10.1109/INFOCOM.2019.8737643.
[23] A. Khalid, A. H. Zahran and C. J. Sreenan, "Optimizing Video QoE for Mobile eMBMS Users in Cellular Networks," IEEE Transactions on Multimedia, VOL. 23, 3166-3178, 2021, doi: 10.1109/TMM.2020.3021229.
[24] ETSI TS 136 321, “LTE; Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification (3GPP TS 36.321 version 14.6.0 Release 14)”, V14.6.0 (2018-04)
[25] J. Vargas, C. Thienot and X. Lagrange, "Comparison of MBSFN, SC-PTM and Unicast for Mission Critical Communication," Proceedings of the 24th International Symposium on Wireless Personal Multimedia Communications (WPMC), 2021, pp. 1-6, doi: 10.1109/WPMC52694.2021.9700469.
[26] A. Virdis, G. Stea and G. Nardini, "SimuLTE - A modular system-level simulator for LTE/LTE-A networks based on OMNeT++," Proceedings of the 4th International Conference On Simulation And Modeling Methodologies, Technologies And Applications (SIMULTECH), 2014.
[27] J. Quinlan, A. Zahran, and C. Sreenan, “Datasets for AVC (H.264) and HEVC (H.265) Evaluation of Dynamic Adaptive Streaming over HTTP (DASH),” Proceedings of the ACM Multimedia Systems Conference, May 2016.
[28] G. Araniti, V. Scordamaglia, M. Condoluci, A. Molinaro and A. Iera, "Efficient Frequency Domain Packet scheduler for Point-to-Multipoint transmissions in LTE networks," Proceedings of the IEEE International Conference on Communications (ICC 2012), pp. 4405-4409, 2012, doi: 10.1109/ICC.2012.6364383.
[29] H. Shariatzadeh and S. G. Maghrebi, "Performance of NOMA-eMBMS Cellular Broadcasting for Multicast/Unicast Applications in 5G Networks," Proceedings of the International Symposium on Networks, Computers and Communications (ISNCC), pp. 1-7, 2019 doi: 10.1109/ISNCC.2019.8909143.