# Priority-Driven Resource Allocation with Reuse for Platooning in 5G Vehicular Network
## 1 Introduction  
Vehicle-to-Everything (V2X) communication enhances road safety and traffic management by enabling real-time interaction between vehicles and their environment. Initially developed using Dedicated Short Range Communication (DSRC) based on IEEE 802.11p [1], V2X has evolved with the introduction of Cellular-V2X (C-V2X), a more reliable and scalable standard [2]. DSRC is also reliable, particularly in applications such as Traffic Signal Priority (TSP) in Europe, where it has been widely adopted as the standard solution for municipalities and public transport providers [3]. This progression reflects the growing need for advanced communication technologies to support autonomous vehicles and optimize vehicular network performance. C-V2X expands the range of applications, especially in facilitating communication services between Original Equipment Manufacturers (OEMs). For instance, C-V2X enables seamless communication between vehicles of different manufacturers, supporting use cases like advanced driver assistance systems (ADAS) and vehicle-to-cloud services. C-V2X expands the range of applications, especially in facilitating communication services between Original Equipment Manufacturers (OEMs). For instance,C-V2X enables seamless communication between vehicles of different manufacturers, supporting use cases like advanced driver assistance systems (ADAS) and vehicle-to-cloud services [4]. The 3 rd Generation Partnership Project (3 GPP), an international standards organization for mobile communication technology, introduced a Device-to-Device (D2D) communication standard for Proximity Services (ProSe) using cellular technology in Release 12 (Rel. 12) [5]. Building upon this, 3 GPP developed LTE-V2X, a C-V2X standard, which was introduced in Release 14 (Rel. 14) and further enhanced in Release 15 (Rel. 15) [6]. A key feature of LTE-V2X is the introduction of sidelink communication, a new interface enabling direct Vehicle-to-Vehicle (V2V) communication, facilitating stable, low-latency interactions between vehicles. In Release 16 (Rel. 16), 3 GPP introduced NR-V2X, a standard that integrates the advanced wireless capabilities of 5G New Radio (NR) into V2X communication. NR-V2X offers improved reliability through higher data transmission rates, lower latency, and enhanced resilience against multipath fading, leveraging millimeter-wave bands [7]. Unlike LTE-V2X, NR-V2X supports various communication modes such as unicast, broadcast, and groupcast [8] and is designed to accommodate advanced services such as vehicle platoon, enhanced driving support, extended sensor sharing, and remote driving [9]. In this service, vehicle platoon is a vehicular technology that enables vehicles to travel in coordinated groups, where each vehicle autonomously maintains its speed and distance through communication with other vehicles in the platoon [10]. This technology provides multiple benefits, including enhanced traffic safety, as decreased inter-vehicle spacing reduces aerodynamic drag [11]. Furthermore, platooning improves road utilization efficiency and mitigates the risk of accidents by facilitating real-time vehicular communication [12]. This paper highlights the need for platoon-prioritized resource allocation algorithms to ensure reliable communication in 5G vehicular networks. While existing studies have explored prioritization for certain service packets, research on algorithms specifically tailored for platoon communication remains limited. This gap is critical, as platoon vehicles transmit more frequently, consuming substantial resources, particularly in congested networks, which can exacerbate delays for general vehicles. In response, this paper proposes a simple yet effective platoon-prioritized resource allocation algorithm that combines a priority-based approach with a resource reuse technique. The goal is to improve the communication performance of platoon vehicles while mitigating the delays caused by resource shortages for general vehicles.