Vehicular Mobility Model Research Articles

Modeling the Influence of Internal Factors on Vehicular Mobility Performance

Traffic mobility is significantly influenced by road conditions and the internal factors governing vehicular performance. Internal factors play a crucial role in vehicular mobility, influencing vehicles operate and performance. While existing vehicular mobility models primarily address external factors, external factors such as governor, engine, gear train and differential unit remain underexplored. This study formulates a comprehensive model to address this gap, focusing on the internal components that affect vehicular mobility. The proposed model employs both analytical and numerical methods to derive transfer functions for these subsystems using Matrix Laboratory (MATLAB), aiming to capture the dynamic behavior of vehicles under various conditions. The model was evaluated by examining vehicle transaction times across different road surface qualities, measured by the International Roughness Index (IRI) values of 3.5, 3.0, and 2.0, and tractive forces ranging from 4500 N to 17750 N, with applied pedal forces of 50 N, 100 N, 150 N and 200 N. Results indicated that higher tractive forces lead to reduced transaction times, with IRI values of 3.5 m/km showing a decrease from 122.0 seconds to 31.0 seconds as tractive forces increased from 4500 N to 17750 N. Similarly, for IRI values of 2.0 m/km, the transaction times reduced from 67.5 seconds to 7.5 seconds under the same conditions. The analysis further demonstrated that increased applied pedal forces correspond to higher tractive forces, thereby enhancing vehicular mobility and performance. These findings highlight the critical role of internal factors in optimizing vehicular mobility and performance, suggesting that internal subsystem dynamics should be integrated into future mobility models for more accurate and comprehensive assessments.

Internet of Vehicles Based On Cellular-Vehicle-To-Everything (C-V2X)

In line with the development of automotive and traffic systems, high mobility and density in different road topologies cause scalability and delay issues due to frequent disconnection between communication nodes. From a safety aspect, Cellular-V2X (C-V2X) wireless technology was introduced by the Third Generation Partnership Project Organization (3GPP) to realise the transmission of emergency messages at critical times, anywhere. Specifically, Mode 4 C-V2X supports side-link communication without relying on a base station to provide network coverage. However, Mode 4 is susceptible to several limitations, which include half-duplex transmission, packet collision, and propagation errors that will cause intermittent connectivity issues. It is also difficult to determine appropriate parameter configurations that can increase the spectrum efficiency of dense networks to facilitate reliable and low-latency networks. The objective of this paper is to investigate the effectiveness of a Mode 4 C-V2X system under different road topologies and traffic scenarios. The study adopts a Krauss vehicular mobility model based on SUMO software to model normal and dense networks in a highway and a road intersection scenario, then perform simulation using OMNET++ software to analyse the impact of different physical layer (PHY) configurations such as modulation and coding scheme, packet size, number of resource block allocation, as well as the probability of resource reservation. The results show that the optimal configuration of parameters depends on the scenario. For highway scenarios, a lower MCS and a higher number of RBs are recommended. For road intersection scenarios, a higher MCS and a lower number of RBs are recommended. The packet size should also be in accordance with the requirements of the application used. The findings of this study can be used to assist in the design of an optimal intelligent transportation system using adaptive C-V2X parameters that can be automatically adjusted under different scenarios and network conditions.

Adaptive Resource Allocation of Vehicles under Dynamic Environment

With the rapid development of the Internet of Vehicles (IoV), the capabilities and intelligence of vehicles are rapidly increasing, which will have the potential to support a large number of services for the users of vehicles. However, taking into account the mobility of the vehicle, how to combine the computing resources from nearby vehicles with high mobility and RSUs to provide services collaboratively is a crucial problem. In this paper, we propose an adaptive allocation scheme of computing resources to allocate the resources more reasonably. First, the vehicular mobility model is built to predict the trajectory of vehicles. Second, the sub-networks to execute the V2V communication are constructed according to the prediction of trajectory. Third, the allocation of computing resources from nearby vehicles and RSUs is formulated as an optimization problem and the intelligent optimization algorithm is employed to deal with it. The relative experiments are conducted to verify the effectiveness of the proposed method.

Advanced Resources Reservation in Mobile Cellular Networks: Static vs. Dynamic Approaches under Vehicular Mobility Model

Many studies in literature have shown that the bandwidth of an ongoing flow can dynamically change during multimedia sessions and an efficient bandwidth allocation scheme must be employed. This paper focuses its attention on the management of predictive services in Wireless Infrastructure Dynamic Networks. In particular, two classes of service are considered: NSIS-Mobility Independent Predictive and NSIS-Mobility Dependent Predictive, where NSIS is the Next Steps in Signaling protocol, employed for resources reservation in Integrated Services architectures. A general prediction technique is proposed, based both on the analysis of time spent into a cell by mobile nodes and on the probabilities of hand-in and hand-out events of mobile nodes from wireless cells. User mobility needs to be firstly analyzed and a novel realistic mobility model has been considered, differently from some existing works in which synthetic mobility is generated. The analysis of user mobility is mandatory when the reduction of passive resource reservations for NSIS-MIP users is desired, with a good enhancement in system utilization. Moreover, predictive reservation and admission control schemes have been integrated. The performance of the 2D wireless system is evaluated in terms of average system utilization, system outage probability, number of admitted flows and reservation prediction errors. We provided to carry out an extensive simulation campaign, in order to assess the goodness of the proposed idea: we verified that good results (in terms of perceived utility, bandwidth and admitted flows) can be obtained, outperforming also some existing works.

Traffic-Centric Mesoscopic Analysis of Connectivity in VANETs

Abstract Vehicular ad hoc networks (VANETs) have emerged as an appropriate class of information propagation technology promising to link us even while moving at high speeds. In VANETs, a piece of information propagates through consecutive connections. In the most previous vehicular connectivity analysis, the provided probability density function of intervehicle distance throughout the wide variety of steady-state traffic flow conditions is surprisingly invariant. But, using a constant assumption, generates approximate communication results, prevents us from improving the performance of the current solutions and impedes designing the new applications on VANETs. Hence, in this paper, a mesoscopic vehicular mobility model in a multilane highway with a steady-state traffic flow condition is adopted. To model a traffic-centric distribution for the spatial per-hop progress and the expected spatial per-hop progress, different intervehicle distance distributions are utilized. Moreover, the expected number of hops, distribution of the number of successful multihop forwarding, the expected time delay and the expected connectivity distance are mathematically investigated. Finally, to model the distribution of the connectivity distances, a set of simplistic closed-form traffic-centric equations is proposed. The accuracy of the proposed model is confirmed using an event-based network simulator as well as a road traffic simulator.

-SIMITS2: SIMULATION FRAMEWORK FOR VEHICULAR CLOUD COMPUTING

Vehicular Cloud is a hybrid technology comprising of VANET, cloud computing and wireless communication. VCC facilitates convenient, on demand access to network, storage area, applications and services on pay as you use basis. VCC is formed by pooling the resources from moving vehicles. Due to the prohibitive cost of deploying and implementing such as system in a real world, most research work in VCC rely on simulations for evaluation purpose. The key concept for VCC simulations is a real world vehicular mobility model. In this paper we present a tool SIMITS2 that allows users to easily generate real world mobility models for VCC simulations. The simulation results are obtained when vehicles are moving according to a real world scenario.

Integration of traffic and network simulators for vehicular ad-hoc networks

Simulation is the replication of the process of the real-world process. Research tool selection is important for generating the realistic scenario. VanetMobiSim is used to generate the realistic scenario for vehicular mobility model and that traffic file simulated by network simulator NS-2.34. With the help of this step, one can generate the simulation results and run simulations for different scenarios to evaluate the performance of the on-demand routing protocols for VANET in terms of different performance parameters those are average throughput, PDF, NRL, average end-to-end delay and packet loss. In this paper, discuss the Integration of traffic and network simulators i.e. VanetMobiSim and NS-2 for vehicular adhoc network simulation. That Integration is useful for calculate the throughput for VANETs.

Improving VANET Simulation with Calibrated Vehicular Mobility Traces

Simulation is the most frequently adopted approach for evaluating protocols and algorithms for Vehicular Ad hoc Networks (VANETs) and Delay-Tolerant Networks (DTNs). Usually, simulation tools use mobility traces to build the network topology based on the existing contacts between mobile nodes. However, quality of the traces, in terms of spatial and temporal granularity of each entry in the logfile, is a key factor that impacts the network topology directly. Therefore, the reliability of the results depends strongly on the accurate representation of the real network topology by the vehicular mobility model. We show that five widely adopted existing real vehicular mobility traces present gaps, leading to fallible outcomes. In this work, we propose a solution to fill those gaps, leading to more fine-grained traces, which lead to more trustworthy simulation results. We propose and evaluate a data-based solution using clustering algorithms to fill the gaps of real-world traces. In addition, we also present the evaluation results that compare the communication graph of the original and the calibrated traces using network metrics. The results reveal that the gaps do indeed induce network topologies differing from reality, decreasing the quality of the evaluation results. To contribute to the research community, we have made the calibrated traces publicly available, so that other researchers may adopt them to improve their evaluation results.

A Smart Parking Lot Management System for Scheduling the Recharging of Electric Vehicles

In this paper, we propose a centralized electric vehicles (EVs) recharge scheduling system for parking lots using a realistic vehicular mobility/parking pattern focusing on individual parking lots. We consider two different types of EV based on their mobility/parking patterns: 1) regular EVs; and 2) irregular EVs. An extensive trace-based vehicular mobility model collected from the Canton of Zurich is used for the regular EVs, and a probabilistic pattern built on top of this trace is used for modeling the behavior of irregular EVs. To the extent of our knowledge, this is the first EV charging scheduling study in the literature that takes into account a realistic vehicular mobility pattern focusing on individual parking lots. We compare the performance of our proposed system with two well-known basic scheduling mechanisms, first come first serve and earliest deadline first, with regard to two objective functions: 1) maximizing the total parking lot revenue; and 2) maximizing the total number of EVs fulfilling their requirements. Comparison results show that our proposed system outperforms well-known basic scheduling mechanisms with regards to both objectives. Parking lots managing the recharging of a high number of EVs will greatly benefit from using such recharge scheduling systems in the context of smart cities.

Comparison of Micro- and Macro-Characteristics of Vehicular Mobility Models

Comparison of Micro- and Macro-Characteristics of Vehicular Mobility Models

A novel macroscopic mobility model for vehicular networks

Researchers face a great challenge when evaluating large-scale vehicular ad hoc network solutions. Since it is not feasible to perform real experiments in this case, and there are no large-scale testbeds available, simulation is the most frequently used evaluation technique, which requires a realistic mobility model to provide accurate results. However, building large-scale realistic vehicular mobility models is a difficult task and many important characteristics have been neglected, particularly macroscopic ones. In this work, a realistic vehicular mobility trace is characterized and macroscopic features are inferred. Based on this characterization, we propose and validate a macroscopic mobility model that provides more realistic characteristics to the vehicular network evaluation process. The obtained results contribute to the research community by providing a more realistic macroscopic model that complements many vehicular mobility generators available in the literature.

An Evolving GPSR Protocol in Urban Roundabout Scenario

According to the research of VANET routing protocol, an improved protocol SN-GPSR has been proposed. It is based on the sensitive nodes. The nodes select routing through a special position and steady speed under GPSR protocol. In a crossroads scenario, we designed a vehicular mobility model and simulated it using NS-2. By analyzing the results, the network performance parameters of SN-GPSR have improved above the GPSR, such as delay, packet loss and others.

Generation and Analysis of a Large-Scale Urban Vehicular Mobility Dataset

The surge in vehicular network research has led, over the last few years, to the proposal of countless network solutions specifically designed for vehicular environments. A vast majority of such solutions has been evaluated by means of simulation, since experimental and analytical approaches are often impractical and intractable, respectively. The reliability of the simulative evaluation is thus paramount to the performance analysis of vehicular networks, and the first distinctive feature that has to be properly accounted for is the mobility of vehicles, i.e., network nodes. Notwithstanding the improvements that vehicular mobility modeling has undergone over the last decade, no vehicular mobility dataset is publicly available today that captures both the macroscopic and microscopic dynamics of road traffic over a large urban region. In this paper, we present a realistic synthetic dataset, covering 24 hours of car traffic in a 400- ${\rm km}^{2}$ region around the city of Koln, in Germany. We describe the generation process and outline how the dataset improves the traces currently employed for the simulative evaluation of vehicular networks. We also show the potential impact that such a comprehensive mobility dataset has on the network protocol performance analysis, demonstrating how incomplete representations of vehicular mobility may result in over-optimistic network connectivity and protocol performance.

Realistic Vehicular Mobility Impact of FTM, IDM, IDM-IM and IDM-LC on VANETs

ABSTRACT VANETs are composed of a number of vehicles moving on city roads, able to interconnect with one another without a fixed infrastructure. Improvisation of a new vehicular communication system should entitle a node to travel safely with high speed mobility while maintaining seamless interconnectivity. To evaluate the impact of mobility models such as FTM, IDM, IDM-IM and IDM-LC on VANETs routing protocol, VanetMobiSim is introduced to design a realistic vehicular mobility model for an urban scenario of Dhaka city. The experimental results suggest several issues e.g. lower packet drop rate, delay, jitter and route cost, etc are required to be considered before preparing a realistic application of VANET. The simulation results have been measured by different performance metrics such as drop, delay, jitter, round-trip time, throughput, route cost and mean hop etc. Keywords VANET; AODV; AOMDV; DYMO; OLSR; FTM; IDM-IM; IDM-LC; IDM; IEEE 802.11p;

Effects of Preferred Routes and Destinations on the Performance of Vehicular Network

Vehicular Ad-Hoc Networks (VANET), in which vehicles constitute the mobile nodes in the network, have attracted increasing interest in both academia and industry. However, due to the prohibitive cost of deploying and implementing such a system in the real world, most of the related research relies on simulations for evaluation purposes. A key component for VANET simulations is a realistic vehicular mobility model, as this ensures that the conclusions drawn from simulation experiments will carry through to the real deployments. Node mobility in a vehicular network is strongly affected by the driving behavior such as route choices. While route choice models have been extensively studied in the transportation community, as far as we know, the effects of preferred route and destination on vehicular network simulations have not been discussed much in the networking literature. In this work, we set out to understand the effect of route choices on vehicular network simulation. We also discuss how different destination selection models affect two practical ITS application scenarios: traffic monitoring and event broadcasting. We conclude that selecting a sufficient level of detail in the simulations, such as modeling of route choices, is critical for evaluating VANET protocol design.

Performance assessment of IP over vehicular delay-tolerant networks through the VDTN@Lab testbed

Abstract Vehicular delay-tolerant network (VDTN) is a network architecture based on the delay-tolerant network paradigm, which was designed to provide low-cost asynchronous vehicular communications in environments with disruptions, intermittency, variable delays, and network partition. This article proposes a laboratory testbed for VDTNs, called VDTN@Lab. It aims to support research studies related with the design, emulation, performance evaluation, and diagnose of new VDTN protocols, services, and applications. It intends to demonstrate the applicability of VDTNs over multiple application environments. VDTN@Lab features an emulation capability, allowing live experiments with prototyped hardware and software embedded into robotic cards, desktop, and netbooks computers. The proposed prototype is demonstrated and evaluated with Epidemic, and Spray, and Wait routing protocols, using different combinations of scheduling and dropping policies, in scenarios with different vehicular mobility models (bus movement and random movement across roads).

Efficient sampling and compressive sensing for urban monitoring vehicular sensor networks

Vehicular sensor network (VSN) using vehicle-based sensors is an emerging technology that can provide an inexpensive solution for surveillance and urban monitoring applications. For the constantly moving vehicles, resulting in unpredictable network topology, data transmission in VSN is vulnerable to packet losses, thus deteriorating the surveillance quality. To resolve this problem, a cooperative data sampling and compression approach is proposed. Based on compressive sensing, this approach does not require inter-sensor communication and adopts sparse random projections to remove redundancy in spatially neighbouring measurements. It is experimentally shown that the proposed algorithm provides fairly accurate reconstruction of the field under surveillance, and incurs much less communication traffic load compared to conventional sampling strategies. Practical data sets, including the temperature distribution in Beijing and the global position system (GPS) tracking data of over 6000 taxis in the city, are used in our experiments to verify the reconstruction accuracy and energy efficiency of the scheme. Different vehicular mobility models are also employed to study the impact of movement behavior. Simulation results show that our proposed approach outperforms the conventional sampling and interpolation strategy, which propagates data in uncompressed format, by 5 dB in reconstruction quality and by 50% in communication complexity reduction for the same sampling rate.

Considering driver behaviour in vehicular delay tolerant networks

A key component for vehicular ad-hoc networks (VANET) simulations is a realistic vehicular mobility model, as this ensures that the conclusions drawn from simulation experiments will carry through to the real deployments. Node mobility in a vehicular network is strongly affected by the driving behaviour such as route choices. While route choice models have been extensively studied in the transportation community, as far as we know, the effects of driver behaviour on vehicular network simulations have not been discussed much in the networking literature. In this work, we set out to understand the effects of destination selection vehicular network simulation. We also discuss how different destination selection models affect event broadcasting in ITS application. We conclude that selecting a sufficient level of detail in the simulations, such as modelling of destination selection, is critical for evaluating VANET protocol design.

Gaussian Profile based Vehicular Mobility Modeling

The driving behavior of a person is influenced by a multitude of local and global factors. These include nature of the driver, distance between the source and destination, condition of the road selected by the driver, traffic conditions, time constraints, lane changing, overtaking actions, safe distance, reaction time etc. are vital for modeling the mobility of a vehicle and are largely determined by the driving behavior. In this paper, a profile based model has been proposed to define the mobility behavior of the vehicles. Different types of influence on the mobility have been lumped and the profile of the motion of vehicles has been modeled as a Gaussian profile. In this model, a driver, first, selects the source, destination and his path and then, selects the parameters of the profile according to his/her presumption. Simulation and results show that profile based model is able to generate realistic and smooth mobility patterns.

Impact of Traffic Influxes: Revealing Exponential Intercontact Time in Urban VANETs

Intercontact time between moving vehicles is one of the key metrics in vehicular ad hoc networks (VANETs) and central to forwarding algorithms and the end-to-end delay. Due to prohibitive costs, little work has conducted experimental study on intercontact time in urban vehicular environments. In this paper, we carry out an extensive experiment involving thousands of operational taxies in Shanghai city. Studying the taxi trace data on the frequency and duration of transfer opportunities between taxies, we observe that the tail distribution of the intercontact time, that is, the time gap separating two contacts of the same pair of taxies, exhibits an exponential decay, over a large range of timescale. This observation is in sharp contrast to recent empirical data studies based on human mobility, in which the distribution of the intercontact time obeys a power law. By analyzing a simplified mobility model that captures the effect of hot areas in the city, we rigorously prove that common traffic influxes, where large volume of traffic converges, play a major role in generating the exponential tail of the intercontact time. Our results thus provide fundamental guidelines on design of new vehicular mobility models in urban scenarios, new data forwarding protocols and their performance analysis.