On the Study of Vehicle Density in Intelligent Transportation Systems

Abstract

Vehicular ad hoc networks (VANETs) are wireless communication networks which support cooperative driving among vehicles on the road. The specific characteristics of VANETs favor the development of attractive and challenging services and applications which rely on message exchanging among vehicles. These communication capabilities depend directly on the existence of nearby vehicles able to exchange information. Therefore, higher vehicle densities favor the communication among vehicles. However, vehicular communications are also strongly affected by the topology of the map (i.e., wireless signal could be attenuated due to the distance between the sender and receiver, and obstacles usually block signal transmission). In this paper, we study the influence of the roadmap topology and the number of vehicles when accounting for the vehicular communications capabilities, especially in urban scenarios. Additionally, we consider the use of two parameters: the SJ Ratio (SJR) and the Total Distance (TD), as the topology-related factors that better correlate with communications performance. Finally, we propose the use of a new density metric based on the number of vehicles, the complexity of the roadmap, and its maximum capacity. Hence, researchers will be able to accurately characterize the different urban scenarios and better validate their proposals related to cooperative Intelligent Transportation Systems based on vehicular communications.

Local Voting Games for Misbehavior Detection in VANETs in Presence of Uncertainty

“…To evaluate our analysis, we assume that 40 nodes run the game in an area of 625 m × 625 m (normal density ≈ 100 nodes km 2 in [15]). Since the analysis is probabilistic, we run 100 iterations for each simulation.…”

“…P m = 1, then one can derive an upper bound for the benefit and a lower bound for the detection rate using eqs. (15) and (16), respectively.…”

On the Mobile Communication Requirements for the Demand-Side Management of Electric Vehicles

“…If we consider that the actual throughput of ALOHA access is about 18% of the synchronized scenario [53], the maximum number of EVs that can be managed by a single LoRa base station is on the order of 146 EVs per channel, which corresponds to about 438 EVs per cell, when the three compulsory channels are adopted. In conclusion, if a maximum traffic density of about 400 EV/km 2 is considered [55], the minimum number of LoRa base stations required to serve all the EVs moving inside the urban area is then on the order of about one cell per square km (i.e., equal to 0.91 cell/km 2 ).…”

A Survey on Infrastructure-Based Vehicular Networks

“…Heterogeneous vehicular networks are also considered [115], where heterogeneity may be in wireless access technologies [116], vertical handovers [117], architectures, and autonomous driving [118]. Attention is also devoted to information acquisition [119] (also with crowd sensing [120,121]) and to information dissemination [122][123][124]. The infrastructure is very often present for vehicular connectivity [125], but device-to-device (D2D) solutions gain an increasing importance [18,126].…”