# NR Sidelink Performance Evaluation for Enhanced 5G-V2X Services
## 3 Literature Review
[30] emphasized the standardized technology for cooperative intelligent transport systems and the LTE-V2X mode 4, with particular attention to factors pertaining to traffic load, resource allocation, and Quality of Service (QoS). An analysis in comparison with ITS-G5 was also carried out. The study illustrates how traffic load and sensing-based SPS mechanism parameters significantly affect LTE-V2X performance, and also shows how well LTE-V2X's QoS mechanism performs in a multi-application scenario when compared to ITS-G5. [PERSON] et al. [31] compare the communication mechanisms and performance of two V2X communication technologies, ITS-G5 and C-V2X (LTE-V2X), under a range of use cases. The findings show that ITS-G5 performs well with concurrent LTE data traffic and that LTE-V2X in mode 3 performs poorly because of handovers and eNB scheduling problems. [PERSON] et al. [32] focus on two popular technologies for Vehicle-to-Infrastructure (V2I) communication: the more recent LTE-based technologies, such as LTE in the infrastructural mode (LTE-I) and the LTE Device-to-Device mode 3 (LTE-D2D), and the well-known IEEE 802.11p (DSRC). In assessing various technologies, the study takes into account important parameters such as the packet delivery ratio (PDR) and end-to-end delay in the context of urban V2I communication. The findings show that while LTE-I works well in some situations, DSRC is superior at facilitating V2I communication. On the other hand, the LTE-D2D mode 3 has drawbacks, especially when it comes to its inadequate PDR and significant end-to-end latency. The advantages and disadvantages of these technologies as well as their applicability in various V2I communication scenarios are clarified by this comparative analysis. [PERSON] et al. [33] highlighted the growing importance of vehicle connectivity and autonomous driving characteristics, which focus on assessing two essential communication standards: C-V2X (3 GPP) and ITS-G5 (based on IEEE 802.11p). Using off-the-shelf hardware and a specific vehicle framework called CAMINO, a thorough real-life assessment was carried out under the same traffic conditions to provide an objective comparison. The results show that ITS-G5 has reduced latency in low-density circumstances, while C-V2X PC5 has a greater reach in short-range scenarios. Furthermore, for some use cases, long-range 4G C-V2X shows itself to be a competitive substitute. This experimental investigation provides important information for the advancement of connected and automated driving in the future, including the upcoming 5G technologies. Decentralized Environmental Messages (DENM)s, which are distributed to vehicles asynchronously, warning them of road hazards and incidents, are one type of aperiodic traffic that [PERSON] et al. [10] focused on. Simulations were conducted to investigate scenarios in which periodic and event-triggered messages share the same RR pool(s) in the sidelinkmode of the autonomous NR V2X. The benefits of that message's repetitions and their impact on periodically transmitted messages have both been studied by [PERSON] et al. [10] in various simulation conditions, together with the key factors of the autonomous resource allocation method affecting the delivery of the environmental messages. [PERSON] et al. [34] perform a comparative analysis of two vehicle wireless communication technologies: 3 GPP Rel-14 LTE-V2X, a recent standard in the cellular industry, and IEEE 802.11p-based dedicated short-range communication (DSRC). An overview of the differences between DSRC and LTE's physical layer frame structure and channel models is given at the very beginning. Metrics including the packet reception ratio, packet delivery ratio, signal to interference plus noise ratio, and data packet delay during resource selection are examined in highway scenarios through system-level simulation in order to assess performance. The findings show that while LTE provides better reliability at low vehicle densities, DSRC performs better at high densities.