# 5G V2X Performance Comparison for Different Channel Coding Schemes and Propagation Models
## 5 Conclusions and Future Work
As a result, polar coding has a long way to go to reach the performance of the BCJR-based algorithms and never actually reaches it. On the other hand, LDPC converges very slowly at low SNR and, although it has a great pace of convergence afterwards, cannot maintain the performance of BCJR-based algorithms. To conclude, we showed that turbo codes are the best choice for small data frame lengths in a 5G-V2X communication environment, excluding the case of very small data frames (128 bits) and high SNR cases, where polar coding has better BER performance. A Vehicular Ad Hoc Network (VANET) is a big step towards intelligent transportation systems. Therefore, many manufacturers are supplying vehicles with onboard computing and communication devices, in-car sensors and navigation systems for the deployment of large-scale vehicular networks. By using different sensors, vehicles can collect and interpret information with very high reliability and minimum delay, with the purpose of helping the driver to make a decision, particularly in driver assistance systems. Specifically, applications where vehicles move in coordination, such as a platoon of vehicles, require secure wireless communication to ensure reliable connectivity and safety [73]. These requirements depend strongly on the design of the communication model, especially the physical layer. Therefore, historical data will be needed for the effectiveness of V2X communication models, e.g., different channel coding schemes, under realistic propagation models. These data can be used by industry to train dynamic systems that will select the appropriate parameters of the V2X communication model, depending on the conditions of the physical environment. This study is a springboard to extensive research for the utilisation of turbo coding in small-frame 5G-V2X communications, in terms of communication aspects, in addition to BER performance. Thus, as future work, the impact of other parameters, such as reliability, end-end latency, data rate per vehicle and communication range, should be examined. Further, the behaviour of BER performance in a dynamic communication system, where the communication model and channel state vary in time according to some probabilistic criteria, must be examined. Furthermore, larger frame lengths can be investigated. In that way, we can examine if turbo coding retains its superiority in a more realistic vehicle scenario, where channel states change between LOS, NLOS and NLOSv, and traffic models change between urban and highway in the same communication scenario in real time. Another point of interest is the comparison of our model with geometry-based stochastic models and the confirmation that the latter produce the same qualitative results as presented in this article. Moreover, we can create a channel model that incorporates both Reconfigurable Intelligent Surfaces [74; 75; 76], as beyond-5G (B5G) and -6G infrastructure candidates, as well as beamforming [77; 78; 79]. Finally, another aspect to be considered in the future is extensive investigation of a holistic and dynamically reconfigurable coding scheme that uses BER performance and QoS attributes for choosing the most suitable decoder for a specific SNR. Such a design could be supported by artificial intelligence principles and trade-offs should be determined among performance and computational complexity. Conceptualization, D.C., C.C. and D.K. ; methodology, D.C., C.C. and D.K. ; software, D.C.; validation, D.C., C.C. and D.K. ; formal analysis, D.C., C.C. and D.K. ; investigation, D.C., C.C. and D.K. ; resources, D.C., C.C. and D.K. ; data curation, D.C., C.C. and D.K. ; writing--original draft preparation, D.C., C.C. and D.K. ; writing--review and editing, D.C., C.C., D.K., K.E.A. and G.T.K. ; visualization, D.C., C.C. and D.K. ; supervision, C.C. and D.K. ; project administration, C.C. ; funding acquisition, C.C. All authors have read and agreed to the published version of the manuscript. **Funding:** This research received no external funding.