(IJACSA) International Journal of Advanced Computer Science and Applications, Vol. 12, No. 12, 2021 274 | Page www.ijacsa.thesai.org SG-TSE: Segment-based Geographic Routing and Traffic Light Scheduling for EV Preemption based Negative Impact Reduction on Normal Traffic Shridevi Jeevan Kamble, Manjunath R Kounte School of Electronics and Communication REVA University, Bengaluru-560064, India Abstract—Emergency Vehicles (EVs) play a significant role in giving timely assistance to the general public by saving lives and avoiding property damages. The EV preemption models help the EVs to maintain their speed along their path by pre-clearing the normal vehicles from the path. However, few preemption models are designed in literature, and they lack in minimizing the negative impacts of EV preemption on normal vehicle traffic and also negative impacts of normal vehicle traffic on EV speed. To accomplish such goals, the work proposes a Segment-based Geographic routing and Traffic light Scheduling based EV preemption (SG-TSE) that incorporates two mechanisms: Segment based Geographic Routing (SGR) and Dynamic Traffic Light Scheduling and EV Preemption (DTSE) for efficient EV preemption. Firstly, the SGR utilized a geographic routing model through the Segment Heads (SHs) along the selected route and passed the EV arrival messages to the traffic light controller to pre-clear the normal traffic. Secondly, the DTSE designs effective scheduling at traffic lights by dynamically adjusting the green time phase based on the minimum detection distance of EVs to the intersections. Thus, the EVs are passed through the intersections quickly without negatively impacting normal traffic, even the signal head in the red phase. Moreover, the proposed SG-TSE activates the green phase time at the correct time and minimizes the negative impacts on the EV preemption model. Finally, the performance of SG-TSE is evaluated using Network Simulator-2 (NS-2) with different performance metrics and various network traffic scenarios. Keywords—Emergency vehicle (EV) preemption; Segment- based Geographic routing and Traffic light Scheduling based EV preemption (SG-TSE); geographic routing; Segment based Geographic Routing (SGR); dynamic traffic light scheduling; Dynamic Traffic light Scheduling and EV preemption (DTSE); green phase adjustment I. INTRODUCTION The Vehicular ad hoc networks (VANETs) enable real- time communication among the roadside vehicles with the support of roadside infrastructure [1]. The VANETs receive high popularity among researchers owing to the application diversity [2]. The VANET applications are mainly categorized into safety and infotainment. In infotainment applications, the vehicles exchange messages about parking areas and hotels and make the journey very comfortable. In contrast to infotainment applications, the safety applications alert the drivers about hazardous situations such as crash warning, accident warning, EV preemption, and others. Hence, the safety applications require strict delay bounds compared with comfort applications. The Emergency Vehicle (EV) preemption is one of the prime VANET applications in which the emergency vehicles are quickly navigated from the approaching lane and intersections [3]. The EVs such as ambulances, fire fighting vehicles, police vehicles, and other defense fighting vehicles receive high priority on roads, as they have to reach their destination on time to save human lives and property losses. The traffic lights integrate various preemption methods and assure desired speed to EVs along its selected path to the incident location to benefit such EVs [4]. The Emergency vehicle preemption system (EVP) interrupts the signal timings of normal traffic at the signalized intersections and provides a green band to the EVs along its routes [5]. Thus, the preemption assists the EVs to pass without stopping or waiting at intersections. It potentially minimizes the travel time and shrinks conflicts with other vehicles in the traveling route [6]. However, it may also negatively impact the general vehicle traffic in the approaching lane. It suffers the vehicles not only in the corresponding intersection but also on other neighboring intersections of coordinated signal control. Hence, it is essential to activate the traffic light green phase at the correct time to reduce the negative impact of EV on normal traffic and also pre-clear the roads in an efficient way to minimize the negative impacts of normal traffic on EVs. Owing to the high dynamic nature and frequent link failure, the geographic routing protocols are highly fit for the VANET environment [7]. Therefore, this work proposes a novel EV preemption model in which segment-based geographic routing and effective traffic light scheduling pass the EVs at intersections quickly with the desired speed. By designing efficient EV preemption with timely green phase activation, the proposed SG-TSE diminishes both negative impacts, such as the negative impact on normal traffic due to EV preemption and the negative impact on EV due to normal traffic. The conventional methods handle only negative impact issues, resulting in inappropriate EV preemption and traffic light control. Thus, it leads to losses of human life and property damages. Hence, crucial green phase activation is required with optimal routing strategies. The SE- TSE solves such an issue significantly by splitting the vehicle density of highly congested scenarios into multiple segments and organizing the vehicles with accurate green phase activation. For that the SG-TSE utilizes a geographic routing