## 6 Conclusions and Discussion  
This paper first researches and analyzes the technical improvements of the IEEE 802.11 bd standard and evaluates their possible impacts on V2X performance. Then, we implement key technological improvements in Veins, such as 256-QAM MCS, a 5/6 coding rate, and LDPC coding, to construct a V2X communication simulation module based on the IEEE 802.11 bd standard. Compared to its predecessor, the IEEE 802.11p standard, the IEEE 802.11 bd standard exhibits significant advancements (more than twice) in data transfer rates. In order to evaluate the progress in two other V2X performance metrics, i.e., data throughput and transmission reliability, we utilized the aforementioned module to construct simulations in large-scale dynamic traffic scenarios. The following conclusions were drawn from our simulation results:  
* In large-scale dynamic traffic scenarios, under identical conditions, 802.11 bd achieves nearly equivalent data dissemination results to IEEE 802.11p when sending packets twice as large, demonstrating that 802.11 bd can achieve approximately twice the data throughput of 802.11p;
* In large-scale dynamic simulations under identical conditions, 802.11 bd achieves up to a 20% improvement in data transmission reliability compared to IEEE 802.11p in terms of the data dissemination distance and the number of vehicles that receive data packets. However, this gain rapidly diminishes with increasing data transmission rates and is limited in complex scenarios, as evidenced by the comparison between the two scenarios. We have also researched the properties of data dissemination in IoV and found that the optimization of the V2X standards and the increase in radio signal transmission power and traffic volume positively impact the data dissemination effectiveness. Regarding the V2X standards, under the same simulation scenarios and data transmission modes, 802.11 bd outperforms 802.11p by approximately 10-20% in terms of the number of vehicles that receive data packets and the data dissemination distance. Within the range of 30 to 120 mW of radio signal transmission power, an increase of approximately 30% in the gain can be observed. However, this gain diminishes with higher levels of radio signal transmission power. Simultaneously, the conclusions drawn from traffic volume simulations are even more significant: while the number of vehicles receiving data packets approaches a proportional increase due to the doubling of the traffic volume, the relative increase in the data dissemination distance is rather limited, at approximately 10%. This finding is highly thought-provoking, indicating that as long as there is a certain baseline  
Figure 14: Summary of the impact of transmission power on data dissemination effectiveness. and continuous traffic flow, the overall traffic volume has a limited impact on the data dissemination distance. In conclusion, this research demonstrates the significant advancements of the IEEE 802.11 bd standard in several key V2X performance metrics at the physical layer, while also revealing the properties of data dissemination in realistic traffic scenarios. Moving forward, our focus will shift to exploring the newly introduced communication mechanisms of IEEE 802.11 bd, such as NON_NGV_10 repetition transmission and non-NGV duplicate PPDU. By designing strategies at the application layer in Veins to refine these mechanisms, we hope to guide higher-level standard architectures and unleash the full potential of IEEE 802.11 bd. The implementation of another NGV standard, NR-V2X, is also planned, and we expect to compare it with IEEE 802.11 bd to provide a reference for the comprehensive application of NGV. Conceptualization, S.G.; methodology, S.X. and S.G.; software, S.X. ; validation, S.X. ; formal analysis, S.G. and S.X. ; investigation, S.X. ; resources, S.G., S.X. and X.L. ; data curation, S.X. ; writing--original draft preparation, S.X. ; writing--review and editing, S.G. and S.X. ; visualization, S.X. ; supervision, S.G. and X.L.