Publications
21.
Delooz, Q.; Festag, A.; Vinel, A.
Congestion Aware Objects Filtering for Collective Perception Proceedings Article
In: 16th International Workshop on Communication Technologies for Vehicles (Nets4Cars), colocated with International Conference on Networked Systems 2021(NetSys 2021), published in Electronic Communications of the EASST, Virtual, 2021, (Vol. 80).
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication
@inproceedings{Delooz:Nets4Cars:2021,
title = {Congestion Aware Objects Filtering for Collective Perception},
author = {Q. Delooz and A. Festag and A. Vinel},
url = {https://festag-net.de/wp-content/uploads/2021_Delooz_Nets4Cars.pdf},
doi = {10.14279/tuj.eceasst.80.1160},
year = {2021},
date = {2021-09-13},
urldate = {2021-12-15},
booktitle = {16th International Workshop on Communication Technologies for Vehicles (Nets4Cars), colocated with International Conference on Networked Systems 2021(NetSys 2021), published in Electronic Communications of the EASST},
address = {Virtual},
abstract = {This paper addresses collective perception for connected and automated driving. It proposes the adaptation of filtering rules based on the currently available channel resources, referred to as Enhanced DCC-Aware Filtering (EDAF).},
note = {Vol. 80},
keywords = {Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
This paper addresses collective perception for connected and automated driving. It proposes the adaptation of filtering rules based on the currently available channel resources, referred to as Enhanced DCC-Aware Filtering (EDAF).
22.
Song, R.; Festag, A.
Analysis of Existing Approaches for Information Sharing in Cooperative Intelligent Transport Systems – V2X Messaging and SENSORIS Proceedings Article
In: FISITA World Congress, Virtual, 2021.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication
@inproceedings{Song:FISITA:2021,
title = {Analysis of Existing Approaches for Information Sharing in Cooperative Intelligent Transport Systems – V2X Messaging and SENSORIS},
author = {R. Song and A. Festag},
url = {https://www.fisita.com/diary/fisita-world-mobility-summit-2021},
doi = {10.46720/F2020-ACM-012},
year = {2021},
date = {2021-09-01},
urldate = {2021-09-01},
booktitle = {FISITA World Congress},
address = {Virtual},
abstract = {Information sharing is essential for connected and automated driving and smart traffic driven by big data. It enables the acquisition of knowledge in cooperative intelligent transport systems (C-ITS), which ultimately increases the integrity and accuracy of road environmental data and thereby improves the efficiency and safety of the traffic system. Moreover, many cloud services and applications, such as self-healing High-Definition Map (HD Maps), demand massive information sharing by means of vehicle-to-X (V2X) communications. In this paper, we review two existing frameworks for information sharing in C-ITS, which are open, standardized and commonly accepted: V2X Messaging focuses on road safety and traffic efficiency based on ad hoc communications among vehicles, the roadside infrastructure and backends. SENSORIS primarily targets at data sharing with and among clouds, specifically for HD Maps. We analyze both frameworks considering technical criteria and selected use cases. Finally, we propose a hybrid network software architecture that combines both information sharing approaches and facilitates interworking between SENSORIS and V2X Messaging in order to enhance C-ITS applications.},
keywords = {Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
Information sharing is essential for connected and automated driving and smart traffic driven by big data. It enables the acquisition of knowledge in cooperative intelligent transport systems (C-ITS), which ultimately increases the integrity and accuracy of road environmental data and thereby improves the efficiency and safety of the traffic system. Moreover, many cloud services and applications, such as self-healing High-Definition Map (HD Maps), demand massive information sharing by means of vehicle-to-X (V2X) communications. In this paper, we review two existing frameworks for information sharing in C-ITS, which are open, standardized and commonly accepted: V2X Messaging focuses on road safety and traffic efficiency based on ad hoc communications among vehicles, the roadside infrastructure and backends. SENSORIS primarily targets at data sharing with and among clouds, specifically for HD Maps. We analyze both frameworks considering technical criteria and selected use cases. Finally, we propose a hybrid network software architecture that combines both information sharing approaches and facilitates interworking between SENSORIS and V2X Messaging in order to enhance C-ITS applications.
23.
Hegde, A.; Stahl, R.; Lobo, S.; Festag, A.
Modeling Cellular Network Infrastructure in SUMO Proceedings Article
In: SUMO User Conference, Virtual, 2021.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, modeling, simulation, V2X communication
@inproceedings{Hegde:SUMO:2021,
title = {Modeling Cellular Network Infrastructure in SUMO},
author = {A. Hegde and R. Stahl and S. Lobo and A. Festag},
url = {https://www.eclipse.org/sumo/2021/},
doi = {10.52825/scp.v2i.97},
year = {2021},
date = {2021-09-01},
urldate = {2021-09-01},
booktitle = {SUMO User Conference},
address = {Virtual},
abstract = {Communication networks are becoming an increasingly important part of the mobility system. They allow traffic participants to be connected and to exchange information related to traffic and roads. The information exchange impacts the behavior of traffic participants, such as the selection of travel routes or their mobility dynamics. Considering infrastructure-based networks, the information exchange depends on the availability of the network infrastructure and the quality of the communication links. Specifically in urban areas, today's 4G and 5G networks deploy small cells of high capacity, which do not provide ubiquitous cellular coverage due to their small range, signal blocking, etc. Therefore, the accurate modeling of the network infrastructure and its integration in simulation scenarios in microscopic traffic simulation software is gaining relevance. Unlike traffic infrastructure, such as traffic lights, the simulation of a cellular network infrastructure is not natively supported in SUMO. Instead, the protocols, functions and entities of the communication system with the physical wireless transmission are modeled in a dedicated and specialized network simulator that is coupled with SUMO. The disadvantage of this approach is that the simulated SUMO entities, typically vehicles, are not aware which portions of the roads are covered by wireless cells and what quality the wireless communication links have.},
keywords = {Cooperative ITS, Intelligent Transport Systems, modeling, simulation, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
Communication networks are becoming an increasingly important part of the mobility system. They allow traffic participants to be connected and to exchange information related to traffic and roads. The information exchange impacts the behavior of traffic participants, such as the selection of travel routes or their mobility dynamics. Considering infrastructure-based networks, the information exchange depends on the availability of the network infrastructure and the quality of the communication links. Specifically in urban areas, today's 4G and 5G networks deploy small cells of high capacity, which do not provide ubiquitous cellular coverage due to their small range, signal blocking, etc. Therefore, the accurate modeling of the network infrastructure and its integration in simulation scenarios in microscopic traffic simulation software is gaining relevance. Unlike traffic infrastructure, such as traffic lights, the simulation of a cellular network infrastructure is not natively supported in SUMO. Instead, the protocols, functions and entities of the communication system with the physical wireless transmission are modeled in a dedicated and specialized network simulator that is coupled with SUMO. The disadvantage of this approach is that the simulated SUMO entities, typically vehicles, are not aware which portions of the roads are covered by wireless cells and what quality the wireless communication links have.
24.
Volk, G.; Delooz, Q.; Schiegg, F. A.; vonBernuth, A.; Festag, A.; Bringmann, O.
Towards Realistic Evaluation of Collective Perception for Connected and Automated Driving Proceedings Article
In: IEEE International Intelligent Transportation Systems Conference (ITSC), pp. 1049-1056, Virtual, 2021.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication
@inproceedings{Volk:ITSC:2021,
title = {Towards Realistic Evaluation of Collective Perception for Connected and Automated Driving},
author = {G. Volk and Q. Delooz and F. A. Schiegg and A. vonBernuth and A. Festag and O. Bringmann},
url = {https://ieeexplore.ieee.org/document/9564783},
doi = {10.1109/ITSC48978.2021.9564783},
year = {2021},
date = {2021-09-01},
urldate = {2021-09-01},
booktitle = {IEEE International Intelligent Transportation Systems Conference (ITSC)},
pages = {1049-1056},
address = {Virtual},
abstract = {Collective perception in Vehicle-to-Everything (V2X) communications allows vehicles to exchange preprocessed sensor data with other traffic participants. It is currently standardized by ETSI as a second generation V2X communication service. The use of collective perception as a communication service for future fully autonomous driving requires a thorough evaluation and validation. Most of the previous work on collective perception has considered large scale-simulations with a focus on communications. However, the perception pipeline used for collective perception is equally important and must not be neglected or over-simplified. Also, to study collective perception in detail, large-scale field testing is practically infeasible. In this paper we extend an existing simulation framework with a realistic model for V2X communications and sensor-data based processing delays. The result is a simulation framework that incorporates the entire collective perception pipeline, which enables to comprehensively study sensor-based perception. We demonstrate the capabilities of this enhanced framework by analyzing the delay of each component involved in the perception pipeline. This allows a detailed insight in end-to-end delays and the age of information within the environmental model of autonomous vehicles.},
keywords = {Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
Collective perception in Vehicle-to-Everything (V2X) communications allows vehicles to exchange preprocessed sensor data with other traffic participants. It is currently standardized by ETSI as a second generation V2X communication service. The use of collective perception as a communication service for future fully autonomous driving requires a thorough evaluation and validation. Most of the previous work on collective perception has considered large scale-simulations with a focus on communications. However, the perception pipeline used for collective perception is equally important and must not be neglected or over-simplified. Also, to study collective perception in detail, large-scale field testing is practically infeasible. In this paper we extend an existing simulation framework with a realistic model for V2X communications and sensor-data based processing delays. The result is a simulation framework that incorporates the entire collective perception pipeline, which enables to comprehensively study sensor-based perception. We demonstrate the capabilities of this enhanced framework by analyzing the delay of each component involved in the perception pipeline. This allows a detailed insight in end-to-end delays and the age of information within the environmental model of autonomous vehicles.
25.
Maksimovski, D.; Festag, A.; Facchi, C.
A Survey on Decentralized Cooperative Maneuver Coordination for Connected and Automated Vehicles Proceedings Article
In: Conference on Vehicle Technology and Intelligent Transport Systems (VEHITS), Virtual, 2021.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, maneuver coordination, V2X communication, vehicle automation
@inproceedings{Maksimovski:VEHITS:2021,
title = {A Survey on Decentralized Cooperative Maneuver Coordination for Connected and Automated Vehicles},
author = {D. Maksimovski and A. Festag and C. Facchi},
url = {https://www.scitepress.org/Papers/2021/104425/104425.pdf},
doi = {10.5220/0010442501000111},
year = {2021},
date = {2021-09-01},
urldate = {2021-09-01},
booktitle = {Conference on Vehicle Technology and Intelligent Transport Systems (VEHITS)},
address = {Virtual},
abstract = {V2X communications can be applied for maneuver coordination of automated vehicles, where the vehicles exchange messages to inform each other of their driving intentions and to negotiate for joint maneuvers. For motion and maneuver planning of automated vehicles, the cooperative maneuver coordination extends the perception range of the sensors, enhances the planning horizon and allows complex interactions among the vehicles. For specific scenarios, various schemes for maneuver coordination of connected automated vehicles exist. Recently, several proposals for maneuver coordination have been made that address generic instead of specific scenarios and apply different schemes for the message exchange of driving intentions and maneuver negotiation. This paper presents use cases for maneuver coordination and classifies existing generic approaches for decentralized maneuver coordination considering implicit and explicit trajectory broadcast, cost values and space-time reservation. We systematically describe the approaches, compare them and derive future research topics.},
keywords = {Cooperative ITS, Intelligent Transport Systems, maneuver coordination, V2X communication, vehicle automation},
pubstate = {published},
tppubtype = {inproceedings}
}
V2X communications can be applied for maneuver coordination of automated vehicles, where the vehicles exchange messages to inform each other of their driving intentions and to negotiate for joint maneuvers. For motion and maneuver planning of automated vehicles, the cooperative maneuver coordination extends the perception range of the sensors, enhances the planning horizon and allows complex interactions among the vehicles. For specific scenarios, various schemes for maneuver coordination of connected automated vehicles exist. Recently, several proposals for maneuver coordination have been made that address generic instead of specific scenarios and apply different schemes for the message exchange of driving intentions and maneuver negotiation. This paper presents use cases for maneuver coordination and classifies existing generic approaches for decentralized maneuver coordination considering implicit and explicit trajectory broadcast, cost values and space-time reservation. We systematically describe the approaches, compare them and derive future research topics.
26.
Otto, T.; Festag, A.
Mehr Augen für sichereres Fahren - Car-to-X Kommunikation unterstützt Verkehrskoordination an Kreuzungen Miscellaneous
InnoVision, 2021.
Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, V2X communication
@misc{Otto:InnoVisions:2021,
title = {Mehr Augen für sichereres Fahren - Car-to-X Kommunikation unterstützt Verkehrskoordination an Kreuzungen},
author = {T. Otto and A. Festag},
url = {https://www.fraunhofer-innovisions.de/mobilitaet/mehr-augen-fuer-sichereres-fahren},
year = {2021},
date = {2021-03-21},
urldate = {2021-03-21},
howpublished = {InnoVision},
keywords = {Cooperative ITS, Intelligent Transport Systems, V2X communication},
pubstate = {published},
tppubtype = {misc}
}
27.
Hegde, A.; Festag, A.
Mode Switching Performance in Cellular-V2X Proceedings Article
In: IEEE Vehicular Networking Conference (VNC), virtual, 2020.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, performance, V2X communication
@inproceedings{Hegde:VNC:2020,
title = {Mode Switching Performance in Cellular-V2X},
author = {A. Hegde and A. Festag},
url = {https://ieeexplore.ieee.org/document/9318394},
doi = {10.1109/VNC51378.2020.9318394},
year = {2020},
date = {2020-12-16},
urldate = {2020-12-16},
booktitle = {IEEE Vehicular Networking Conference (VNC)},
address = {virtual},
abstract = {Cellular-V2X aims at supporting road safety and traffic management applications and introduces sidelink (PC5) as a new interface. These applications primarily rely on periodic broadcast of small-sized periodic messages and event-triggered notification messages. A key requirement of the applications is to facilitate uninterrupted exchange of messages among the vehicles irrespective of whether the vehicles are inside a base station coverage or not. In Cellular-V2X standardization, two resource allocation modes have been specified: when a vehicle is located inside the coverage of the cellular network, the corresponding base station manages the transmission resources for the direct message exchange. When a vehicle is outside of cellular coverage, it allocates its resources autonomously. The modes are also referred to as ``managed'' and ``unmanaged'' mode, or mode 3 and mode 4, respectively. In situations with imperfect cellular coverage by base stations, a vehicle needs to perform mode switching. The present work aims to understand the different phases of the mode switching procedure and to study the latency involved in each phase for both switching scenarios, mode 3 to 4 and vice versa. Considering a realistic road traffic scenario with a highway tunnel, we assess the impact of mode switch latency on the data transmission for a selected mode switch strategy.},
keywords = {Cooperative ITS, Intelligent Transport Systems, performance, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
Cellular-V2X aims at supporting road safety and traffic management applications and introduces sidelink (PC5) as a new interface. These applications primarily rely on periodic broadcast of small-sized periodic messages and event-triggered notification messages. A key requirement of the applications is to facilitate uninterrupted exchange of messages among the vehicles irrespective of whether the vehicles are inside a base station coverage or not. In Cellular-V2X standardization, two resource allocation modes have been specified: when a vehicle is located inside the coverage of the cellular network, the corresponding base station manages the transmission resources for the direct message exchange. When a vehicle is outside of cellular coverage, it allocates its resources autonomously. The modes are also referred to as ``managed'' and ``unmanaged'' mode, or mode 3 and mode 4, respectively. In situations with imperfect cellular coverage by base stations, a vehicle needs to perform mode switching. The present work aims to understand the different phases of the mode switching procedure and to study the latency involved in each phase for both switching scenarios, mode 3 to 4 and vice versa. Considering a realistic road traffic scenario with a highway tunnel, we assess the impact of mode switch latency on the data transmission for a selected mode switch strategy.
28.
Delooz, Q.; Riebl, R.; Festag, A.; Vinel, A.
Design and Performance of Congestion-Aware Collective Perception Proceedings Article
In: IEEE Vehicular Networking Conference (VNC), virtual, 2020.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication
@inproceedings{Delooz:VNC:2020,
title = {Design and Performance of Congestion-Aware Collective Perception},
author = {Q. Delooz and R. Riebl and A. Festag and A. Vinel},
url = {https://ieeexplore.ieee.org/document/9318335},
doi = {10.1109/VNC51378.2020.9318335},
year = {2020},
date = {2020-12-16},
urldate = {2021-09-01},
booktitle = {IEEE Vehicular Networking Conference (VNC)},
address = {virtual},
abstract = {In vehicular ad hoc networks, congestion control prevents the overloading of the wireless channel and ensures a fair distribution of the transmission resources. For ITS-G5-based vehicular networks, the European standardization by ETSI has specified a Decentralized Congestion Control (DCC) function at the access layer. This function controls the medium occupancy of a network node by enforcing maximum values of message transmission parameters. In the present paper, we study the impact of DCC on the performance of the collective perception service. This communication service enables vehicles and roadside stations to exchange messages with pre-processed sensor data. Since collective perception can considerably contribute to the network load, the transmission restrictions imposed by DCC affect the performance of the information exchange and the quality of the perception. The current design of collective perception in ETSI does not adapt the messages to the actual DCC constraints. We propose a novel approach for DCC-aware collective perception, which enhances the object filtering process of collective perception by dynamically adapting the message size to the DCC constraints and implicitly the message generation rate. Compared to the current ETSI design, the obtained results show a better quality of perception and channel usage, with a reduced message generation rate.},
keywords = {Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
In vehicular ad hoc networks, congestion control prevents the overloading of the wireless channel and ensures a fair distribution of the transmission resources. For ITS-G5-based vehicular networks, the European standardization by ETSI has specified a Decentralized Congestion Control (DCC) function at the access layer. This function controls the medium occupancy of a network node by enforcing maximum values of message transmission parameters. In the present paper, we study the impact of DCC on the performance of the collective perception service. This communication service enables vehicles and roadside stations to exchange messages with pre-processed sensor data. Since collective perception can considerably contribute to the network load, the transmission restrictions imposed by DCC affect the performance of the information exchange and the quality of the perception. The current design of collective perception in ETSI does not adapt the messages to the actual DCC constraints. We propose a novel approach for DCC-aware collective perception, which enhances the object filtering process of collective perception by dynamically adapting the message size to the DCC constraints and implicitly the message generation rate. Compared to the current ETSI design, the obtained results show a better quality of perception and channel usage, with a reduced message generation rate.
29.
Senel, N.; Elger, G.; Festag, A.
Sensor Time Synchronization in Smart Road Infrastructure Proceedings Article
In: FISITA World Congress, Virtual, 2020.
Abstract | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication
@inproceedings{Senel:FISITA:2020,
title = {Sensor Time Synchronization in Smart Road Infrastructure},
author = {N. Senel and G. Elger and A. Festag},
year = {2020},
date = {2020-11-24},
urldate = {2020-11-24},
booktitle = {FISITA World Congress},
address = {Virtual},
abstract = {To enable efficient and secure traffic, the roadside infrastructure can be equipped with sensor nodes, which contain the physical sensors, a data link for vehicle-to-infrastructure (V2I) communication and computing capabilities for data processing. The sensor nodes in the infrastructure will support the future autonomous road traffic. A precise time synchronization between the sensors and the central fusion node is a requirement for accurate detection of the roadside users' trajectories. In this paper, two architecture options are considered: (i) distributed pre-processing with transmission of compressed data over wireless links, i.e., WLAN, for temporary setups and (ii) centralized processing with transmission of raw data over wired links for permanent installations, i.e., Ethernet. A prototype system is described, which is composed of cameras, computing hardware and network equipment running under Linux using the Robotic Operating System (ROS) as middle-ware. For both architectures, the Network Time Protocol (NTP/Chrony) for time synchronization and ROS specific functions for data synchronization are used. Measurement results for the two architectures are presented and compared.},
keywords = {Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
To enable efficient and secure traffic, the roadside infrastructure can be equipped with sensor nodes, which contain the physical sensors, a data link for vehicle-to-infrastructure (V2I) communication and computing capabilities for data processing. The sensor nodes in the infrastructure will support the future autonomous road traffic. A precise time synchronization between the sensors and the central fusion node is a requirement for accurate detection of the roadside users' trajectories. In this paper, two architecture options are considered: (i) distributed pre-processing with transmission of compressed data over wireless links, i.e., WLAN, for temporary setups and (ii) centralized processing with transmission of raw data over wired links for permanent installations, i.e., Ethernet. A prototype system is described, which is composed of cameras, computing hardware and network equipment running under Linux using the Robotic Operating System (ROS) as middle-ware. For both architectures, the Network Time Protocol (NTP/Chrony) for time synchronization and ROS specific functions for data synchronization are used. Measurement results for the two architectures are presented and compared.
30.
Hegde, A.; Festag, A.
Artery-C: An OMNeT++ Based Discrete Event Simulation Framework for Cellular V2X (Short version) Proceedings Article
In: ACM 23rd Annual International Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems (MSWiM), pp. 47–51, Alicante, Spain, 2020.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, simulation, V2X communication
@inproceedings{Hegde:MSWIM:2020,
title = {Artery-C: An OMNeT++ Based Discrete Event Simulation Framework for Cellular V2X (Short version)},
author = {A. Hegde and A. Festag},
url = {https://dl.acm.org/doi/10.1145/3416010.3423240},
doi = {10.1145/3416010.3423240},
year = {2020},
date = {2020-11-16},
urldate = {2020-11-16},
booktitle = {ACM 23rd Annual International Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems (MSWiM)},
pages = {47–51},
address = {Alicante, Spain},
abstract = {Introduced with LTE Release 14, Cellular V2X enables device-to-device communication to support road safety and traffic efficiency applications. We present Artery-C, a simulation framework for the performance evaluation of Cellular V2X protocols and V2X applications. Our simulator relies on the simulation framework SimuLTE and substantially extends it by implementing control and user planes, a dedicated sidelink interface with specific focus on dynamic mode switching and some advanced features of 5G mobile networks, such as variable numerologies. Artery-C integrates seamlessly into the simulation framework Artery, which enables the simulation of standardized V2X messages at the facilities layer as well as the coupling to the mobility simulator SUMO. In order to demonstrate the capabilities of Artery-C, we evaluate V2X-based platooning as a representative use case and present results for mode 3, mode 4 and mode switching in a highway scenario.},
keywords = {Cooperative ITS, Intelligent Transport Systems, simulation, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
Introduced with LTE Release 14, Cellular V2X enables device-to-device communication to support road safety and traffic efficiency applications. We present Artery-C, a simulation framework for the performance evaluation of Cellular V2X protocols and V2X applications. Our simulator relies on the simulation framework SimuLTE and substantially extends it by implementing control and user planes, a dedicated sidelink interface with specific focus on dynamic mode switching and some advanced features of 5G mobile networks, such as variable numerologies. Artery-C integrates seamlessly into the simulation framework Artery, which enables the simulation of standardized V2X messages at the facilities layer as well as the coupling to the mobility simulator SUMO. In order to demonstrate the capabilities of Artery-C, we evaluate V2X-based platooning as a representative use case and present results for mode 3, mode 4 and mode switching in a highway scenario.
31.
Delooz, Q.; Festag, A.; Vinel, A.
Revisiting Message Generation Strategies for Collective Perception in Connected and Automated Driving Proceedings Article
In: 9th International Conference on Advances in Vehicular Systems, Technologies and Applications (VEHICULAR), Porto, Portugal, 2020, ISBN: 978-1-61208-795-5.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication
@inproceedings{Delooz:VEHICULAR:2020,
title = {Revisiting Message Generation Strategies for Collective Perception in Connected and Automated Driving},
author = {Q. Delooz and A. Festag and A. Vinel},
url = {https://www.thinkmind.org/articles/vehicular_2020_1_80_30039.pdf},
isbn = {978-1-61208-795-5},
year = {2020},
date = {2020-10-18},
urldate = {2020-10-18},
booktitle = {9th International Conference on Advances in Vehicular Systems, Technologies and Applications (VEHICULAR)},
address = {Porto, Portugal},
abstract = {Collective perception enables vehicles to exchange preprocessed sensor data and is being standardized as a 2nd generation V2X communication service. The European standardization in ETSI foresees the exchange of detected objects and defined a dedicated message type (Collective Perception Message, CPM) with rules to decide when and with which objects the message should be generated, referred to as generation rules. The choice of these rules is not straightforward and influences both channel load and perception quality. For the object inclusion, ETSI currently follows a similar policy as for the generation of Cooperative Awareness Messages (CAM): The objects are filtered based on their dynamics. We regard this approach as conservative. The present paper revisits the generation rules for the CPM and applies two approaches for object inclusion to the CPM – the conservative strategy of ETSI and a more 'greedy' strategy. We assess the performance by discrete-event simulations in a scenario representing a city with realistic vehicle densities and mobility patterns. The simulations take into account the effects imposed by decentralized congestion control. Considering that ETSI currently follows the conservative strategy, we conclude that the application of a greedy strategy improves the perception quality in low-density scenarios.},
keywords = {Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
Collective perception enables vehicles to exchange preprocessed sensor data and is being standardized as a 2nd generation V2X communication service. The European standardization in ETSI foresees the exchange of detected objects and defined a dedicated message type (Collective Perception Message, CPM) with rules to decide when and with which objects the message should be generated, referred to as generation rules. The choice of these rules is not straightforward and influences both channel load and perception quality. For the object inclusion, ETSI currently follows a similar policy as for the generation of Cooperative Awareness Messages (CAM): The objects are filtered based on their dynamics. We regard this approach as conservative. The present paper revisits the generation rules for the CPM and applies two approaches for object inclusion to the CPM – the conservative strategy of ETSI and a more 'greedy' strategy. We assess the performance by discrete-event simulations in a scenario representing a city with realistic vehicle densities and mobility patterns. The simulations take into account the effects imposed by decentralized congestion control. Considering that ETSI currently follows the conservative strategy, we conclude that the application of a greedy strategy improves the perception quality in low-density scenarios.
32.
Hegde, A.; Festag, A.
Artery-C: An OMNeT++ Based Discrete Event Simulation Framework for Cellular V2X (Long version) Journal Article
In: arXiv, 2020, (arXiv:2009.05724 [cs.NI]).
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, modeling, simulation, V2X communication
@article{Hegde:ARXIV:2020,
title = {Artery-C: An OMNeT++ Based Discrete Event Simulation Framework for Cellular V2X (Long version)},
author = {A. Hegde and A. Festag},
url = {https://arxiv.org/abs/2009.05724},
year = {2020},
date = {2020-09-12},
urldate = {2020-09-12},
journal = {arXiv},
abstract = {Cellular Vehicle-to-X (Cellular V2X) is a communication technology that aims to facilitate the communication among vehicles and with the roadside infrastructure. Introduced with LTE Release 14, Cellular V2X enables device-to-device communication to support road safety and traffic efficiency applications. We present Artery-C, a simulation framework for the performance evaluation of Cellular V2X protocols and V2X applications. Our simulator relies on the simulation framework SimuLTE and substantially extends it by implementing control and user planes. Besides the vehicle-to-network communication via the up-/downlink interface, it provides vehicle-to-vehicle and vehicle-infrastructure communication via the sidelink interface using the managed and the unmanaged mode of Cellular V2X (mode 3 and 4, respectively). The simulator also implements advanced features of 5G mobile networks, such as variable numerologies. For the transmission of of V2X messages, it adds a non-IP interface. Artery-C integrates seamlessly into the simulation framework Artery, which enables the simulation of standardized V2X messages at the facilities layer as well as the coupling to the mobility simulator SUMO. A specific feature of Artery-C is the support of dynamic switching between all modes of Cellular V2X. In order to demonstrate the capabilities of Artery-C, we evaluate V2X-based platooning as a representative use case and present results for mode 3, mode 4 and mode switching in a highway scenario.},
note = {arXiv:2009.05724 [cs.NI]},
keywords = {Cooperative ITS, Intelligent Transport Systems, modeling, simulation, V2X communication},
pubstate = {published},
tppubtype = {article}
}
Cellular Vehicle-to-X (Cellular V2X) is a communication technology that aims to facilitate the communication among vehicles and with the roadside infrastructure. Introduced with LTE Release 14, Cellular V2X enables device-to-device communication to support road safety and traffic efficiency applications. We present Artery-C, a simulation framework for the performance evaluation of Cellular V2X protocols and V2X applications. Our simulator relies on the simulation framework SimuLTE and substantially extends it by implementing control and user planes. Besides the vehicle-to-network communication via the up-/downlink interface, it provides vehicle-to-vehicle and vehicle-infrastructure communication via the sidelink interface using the managed and the unmanaged mode of Cellular V2X (mode 3 and 4, respectively). The simulator also implements advanced features of 5G mobile networks, such as variable numerologies. For the transmission of of V2X messages, it adds a non-IP interface. Artery-C integrates seamlessly into the simulation framework Artery, which enables the simulation of standardized V2X messages at the facilities layer as well as the coupling to the mobility simulator SUMO. A specific feature of Artery-C is the support of dynamic switching between all modes of Cellular V2X. In order to demonstrate the capabilities of Artery-C, we evaluate V2X-based platooning as a representative use case and present results for mode 3, mode 4 and mode switching in a highway scenario.
33.
Delooz, Q.; Festag, A.
Network Load Adaptation for Collective Perception in V2X Communication Proceedings Article
In: IEEE International Conference on Connected Vehicles and Expo (ICCVE), Graz, Austria, 2019.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication
@inproceedings{Delooz:ICCVE:2019,
title = {Network Load Adaptation for Collective Perception in V2X Communication},
author = {Q. Delooz and A. Festag},
url = {https://ieeexplore.ieee.org/document/8964988},
doi = {10.1109/ICCVE45908.2019.8964988},
year = {2019},
date = {2019-11-04},
urldate = {2019-11-04},
booktitle = {IEEE International Conference on Connected Vehicles and Expo (ICCVE)},
address = {Graz, Austria},
abstract = {Collective perception uses V2X communications to increase the perception capabilities of vehicles. Relying on the perceived data from their local sensors, nodes exchange information about the objects they detect in their surroundings. An object can be anything significant for the nodes' safety, e.g., obstacles on the road, other vehicles or pedestrians. The amount of data generated by each node is determined by the number of perceived objects and the generation frequency of the messages carrying the detected objects. Considering the limited bandwidth of the wireless channel, the data load generated by collective perception can easily exceed the channel capacity. In this paper, we investigate three schemes that filter the number of objects in the messages and thereby adjust the network load in order to optimize the transmission of perceived objects. Our simulation-based performance evaluation indicates that the use of filtering is an effective approach to improve network-related performance metrics, whereas the expected impairment of the perception quality is rather small. The comparison of the filtering algorithms provide insights into the tradeoff between network-related metrics and perception quality.},
keywords = {Cooperative ITS, Intelligent Transport Systems, sensor data sharing, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
Collective perception uses V2X communications to increase the perception capabilities of vehicles. Relying on the perceived data from their local sensors, nodes exchange information about the objects they detect in their surroundings. An object can be anything significant for the nodes' safety, e.g., obstacles on the road, other vehicles or pedestrians. The amount of data generated by each node is determined by the number of perceived objects and the generation frequency of the messages carrying the detected objects. Considering the limited bandwidth of the wireless channel, the data load generated by collective perception can easily exceed the channel capacity. In this paper, we investigate three schemes that filter the number of objects in the messages and thereby adjust the network load in order to optimize the transmission of perceived objects. Our simulation-based performance evaluation indicates that the use of filtering is an effective approach to improve network-related performance metrics, whereas the expected impairment of the perception quality is rather small. The comparison of the filtering algorithms provide insights into the tradeoff between network-related metrics and perception quality.
34.
Hegde, A.; Festag, A.
Mode Switching Strategies in Cellular-V2X Proceedings Article
In: 10th IFAC Symposium on Intelligent Autonomous Vehicles, Gdansk, Poland, 2019.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, simulation, V2X communication
@inproceedings{Hegde:IFAC:2019,
title = {Mode Switching Strategies in Cellular-V2X},
author = {A. Hegde and A. Festag},
url = {https://www.sciencedirect.com/science/article/pii/S2405896319303829},
doi = {10.1016/j.ifacol.2019.08.052},
year = {2019},
date = {2019-07-03},
urldate = {2019-07-03},
booktitle = {10th IFAC Symposium on Intelligent Autonomous Vehicles},
address = {Gdansk, Poland},
abstract = {Cellular-V2X facilitates a direct communication among vehicles and with the roadside traffic infrastructure. It addresses use cases for safety and traffic efficiency, where data are disseminated in a vehicle's vicinity with short-latency constraints. Cellular-V2X provides two modes: when the vehicle is located in the coverage of the cellular network, the corresponding base station manages the transmission resources for the direct message exchange. In the out-of-coverage mode, the vehicle does not require cellular coverage and allocates its resources autonomously. Though the in-coverage mode is the preferred mode of operation, it is not always available. Due to the vehicle mobility and other reasons, a vehicle may need to dynamically switch between the two modes. Mode switching affects the communication quality since the vehicle cannot send and receive messages during the execution of the switching procedure. We propose three decision strategies for mode switching: forced, signal strength-based and load-based mode switching. We describe the mode switching decision by a cost function and derive individual functions for each of the proposed strategies. Decomposing the overall mode switching procedure into subsequent phases, we understand the different types of latencies incurred at every stage of mode switching.},
keywords = {Cooperative ITS, Intelligent Transport Systems, simulation, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
Cellular-V2X facilitates a direct communication among vehicles and with the roadside traffic infrastructure. It addresses use cases for safety and traffic efficiency, where data are disseminated in a vehicle's vicinity with short-latency constraints. Cellular-V2X provides two modes: when the vehicle is located in the coverage of the cellular network, the corresponding base station manages the transmission resources for the direct message exchange. In the out-of-coverage mode, the vehicle does not require cellular coverage and allocates its resources autonomously. Though the in-coverage mode is the preferred mode of operation, it is not always available. Due to the vehicle mobility and other reasons, a vehicle may need to dynamically switch between the two modes. Mode switching affects the communication quality since the vehicle cannot send and receive messages during the execution of the switching procedure. We propose three decision strategies for mode switching: forced, signal strength-based and load-based mode switching. We describe the mode switching decision by a cost function and derive individual functions for each of the proposed strategies. Decomposing the overall mode switching procedure into subsequent phases, we understand the different types of latencies incurred at every stage of mode switching.
35.
Hung, S. C.; Zhang, X.; Festag, A.; Chen, K. C.; Fettweis, G.
Vehicle-Centric Network Association in Heterogeneous Vehicle-to-Vehicle Networks Journal Article
In: IEEE Transactions on Vehicular Technology, vol. 68, no. 6, pp. 5981-5996, 2019.
Abstract | Links | BibTeX | Tags: Cooperative ITS, handover, Intelligent Transport Systems, optimization, V2X communication
@article{Hung:TransVehTechn:2019,
title = {Vehicle-Centric Network Association in Heterogeneous Vehicle-to-Vehicle Networks},
author = {S. C. Hung and X. Zhang and A. Festag and K. C. Chen and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/8686054},
doi = {10.1109/TVT.2019.2910324},
year = {2019},
date = {2019-04-11},
urldate = {2019-04-11},
journal = {IEEE Transactions on Vehicular Technology},
volume = {68},
number = {6},
pages = {5981-5996},
abstract = {Safe and reliable operation of future autonomous vehicles requires ultra-low latency vehicle-to-vehicle (V2V) networking. However, due to scalability issues of purely ad hoc network, vehicle-to-infrastructure (V2I) communication is still in demand. To avoid interference between V2V and V2I communications, conventional network association such as handover may generate a large amount of control and signaling overhead, especially in environments with high-speed mobility and small-coverage access points. Taking the additional latency caused by the overhead into consideration, a vehicle-centric approach is proposed to guarantee the low-latency requirements of the V2V networks. Different from solely optimizing the latency performance, the proposed approach focuses on effectively operating the network association and resources re-allocation. This avoids the massive exchange of control information and signaling and reduces its impact on latency. The proposed framework for V2V networking can underlay different virtual cells with a constrained network association rate and we can derive the corresponding upper bound of the latency performance. Analysis and simulation results indicate that our scheme successfully guarantees the upper bound of the latency and simultaneously constrains the network association rate, thus limiting the additional control exchange and signaling overhead.},
keywords = {Cooperative ITS, handover, Intelligent Transport Systems, optimization, V2X communication},
pubstate = {published},
tppubtype = {article}
}
Safe and reliable operation of future autonomous vehicles requires ultra-low latency vehicle-to-vehicle (V2V) networking. However, due to scalability issues of purely ad hoc network, vehicle-to-infrastructure (V2I) communication is still in demand. To avoid interference between V2V and V2I communications, conventional network association such as handover may generate a large amount of control and signaling overhead, especially in environments with high-speed mobility and small-coverage access points. Taking the additional latency caused by the overhead into consideration, a vehicle-centric approach is proposed to guarantee the low-latency requirements of the V2V networks. Different from solely optimizing the latency performance, the proposed approach focuses on effectively operating the network association and resources re-allocation. This avoids the massive exchange of control information and signaling and reduces its impact on latency. The proposed framework for V2V networking can underlay different virtual cells with a constrained network association rate and we can derive the corresponding upper bound of the latency performance. Analysis and simulation results indicate that our scheme successfully guarantees the upper bound of the latency and simultaneously constrains the network association rate, thus limiting the additional control exchange and signaling overhead.
36.
Kühlmorgen, S.; Lu, H.; Festag, A.; Kenney, J.; Gemsheim, S.; Fettweis, G.
Evaluation of Congestion-Enabled Forwarding With Mixed Data Traffic in Vehicular Communications Journal Article
In: IEEE Transactions on Intelligent Transportation Systems, vol. 21, no. 1, pp. 233-247, 2019.
Abstract | Links | BibTeX | Tags: ad hoc networking, Cooperative ITS, Intelligent Transport Systems, V2X communication
@article{Kuehlmorgen:IEEETransITS:2020,
title = {Evaluation of Congestion-Enabled Forwarding With Mixed Data Traffic in Vehicular Communications},
author = {S. Kühlmorgen and H. Lu and A. Festag and J. Kenney and S. Gemsheim and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/8617699},
doi = {10.1109/TITS.2018.2890619},
year = {2019},
date = {2019-01-17},
urldate = {2019-01-17},
journal = {IEEE Transactions on Intelligent Transportation Systems},
volume = {21},
number = {1},
pages = {233-247},
abstract = {ITS-G5 is a communication system for vehicle-to-everything communication for road safety and traffic efficiency applications. On the lower layers, it is based on IEEE 802.11 standard and uses a simple ad hoc mode with a random medium access control scheme. Ad hoc networking is realized by a geographical routing scheme that provides single- and multi-hop communication over ITS-G5 links for periodic and event-driven broadcast messages. Specifically, contention-based forwarding (CBF) allows for efficient and reliable multi-hop packet transport by overhearing and timer-based transmission control. To cope with the channel congestion, decentralized congestion control (DCC) adjusts the message rate and ensures that the network load keeps below a predefined threshold of the bandwidth. To enforce a node's message rate, a `` Gatekeeper'' above the MAC and beneath CBF is added. Under high network load, this Gatekeeper introduces an additional queuing delay seen by CBF, which can cause its overhearing function to fail. This contribution studies multi-hop forwarding in the context of DCC with the Gatekeeper and LIMERIC as a rate adaptation algorithm. We propose a congestion-enabled forwarding scheme that, in comparison to existing approaches considering DCC and forwarding separately, restores the efficient operation of CBF, and improves the communication performance in terms of reliability and latency for mixed data traffic composed of single- and multi-hop packets with different priorities. The simulations show the performance improvements in a freeway scenario. An analysis assesses the boundary conditions for CBF and the Gatekeeper. Moreover, the analysis corroborates the simulation.},
keywords = {ad hoc networking, Cooperative ITS, Intelligent Transport Systems, V2X communication},
pubstate = {published},
tppubtype = {article}
}
ITS-G5 is a communication system for vehicle-to-everything communication for road safety and traffic efficiency applications. On the lower layers, it is based on IEEE 802.11 standard and uses a simple ad hoc mode with a random medium access control scheme. Ad hoc networking is realized by a geographical routing scheme that provides single- and multi-hop communication over ITS-G5 links for periodic and event-driven broadcast messages. Specifically, contention-based forwarding (CBF) allows for efficient and reliable multi-hop packet transport by overhearing and timer-based transmission control. To cope with the channel congestion, decentralized congestion control (DCC) adjusts the message rate and ensures that the network load keeps below a predefined threshold of the bandwidth. To enforce a node's message rate, a `` Gatekeeper'' above the MAC and beneath CBF is added. Under high network load, this Gatekeeper introduces an additional queuing delay seen by CBF, which can cause its overhearing function to fail. This contribution studies multi-hop forwarding in the context of DCC with the Gatekeeper and LIMERIC as a rate adaptation algorithm. We propose a congestion-enabled forwarding scheme that, in comparison to existing approaches considering DCC and forwarding separately, restores the efficient operation of CBF, and improves the communication performance in terms of reliability and latency for mixed data traffic composed of single- and multi-hop packets with different priorities. The simulations show the performance improvements in a freeway scenario. An analysis assesses the boundary conditions for CBF and the Gatekeeper. Moreover, the analysis corroborates the simulation.
37.
Fritzsche, R.; Festag, A.
Reliability Maximization with Location-Based Scheduling for Cellular-V2X Communications in Highway Scenarios Proceedings Article
In: IEEE 16th International Conference on Intelligent Transportation Systems Telecommunications (ITST), Lisbon, Portugal, 2018.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, optimization, V2X communication
@inproceedings{Fritzsche:ITST:2018,
title = {Reliability Maximization with Location-Based Scheduling for Cellular-V2X Communications in Highway Scenarios},
author = {R. Fritzsche and A. Festag},
url = {https://ieeexplore.ieee.org/document/8566935},
doi = {10.1109/ITST.2018.8566935},
year = {2018},
date = {2018-10-15},
urldate = {2018-12-10},
booktitle = {IEEE 16th International Conference on Intelligent Transportation Systems Telecommunications (ITST)},
address = {Lisbon, Portugal},
abstract = {Advanced applications in intelligent transport systems (ITS) are based on V2X (vehicle-to-everything) communications. In order to share information about, e.g., vehicle status, critical events or perceived objects in the vicinity, respective services suggest direct communication links (device-to-device) among vehicles, as introduced in ITS-G5 and Cellular-V2X. A major challenge for direct communications systems is the utilization of available radio resources.In this work, we present a resource scheduling scheme based on vehicle locations, aiming to maximize the reliability of message transmission in highway scenarios, considering a given bandwidth. The scheme consists of two steps: first we determine the optimal distance between vehicles utilizing equivalent radio resources. We extend our previous work and provide a closed form solution for the outage probability. The quasi-convex expression can be solved with standard optimization algorithms. In the second step, we propose radio resource allocation strategies that rely on the optimal scheduling distance. Finally, we evaluate the performance of our proposed scheme compared to a fixed scheduling distance.},
keywords = {Cooperative ITS, Intelligent Transport Systems, optimization, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
Advanced applications in intelligent transport systems (ITS) are based on V2X (vehicle-to-everything) communications. In order to share information about, e.g., vehicle status, critical events or perceived objects in the vicinity, respective services suggest direct communication links (device-to-device) among vehicles, as introduced in ITS-G5 and Cellular-V2X. A major challenge for direct communications systems is the utilization of available radio resources.In this work, we present a resource scheduling scheme based on vehicle locations, aiming to maximize the reliability of message transmission in highway scenarios, considering a given bandwidth. The scheme consists of two steps: first we determine the optimal distance between vehicles utilizing equivalent radio resources. We extend our previous work and provide a closed form solution for the outage probability. The quasi-convex expression can be solved with standard optimization algorithms. In the second step, we propose radio resource allocation strategies that rely on the optimal scheduling distance. Finally, we evaluate the performance of our proposed scheme compared to a fixed scheduling distance.
38.
Kühlmorgen, S.; Schmarger, P.; Festag, A.; Fettweis, G.
Simulation-based Evaluation of ETSI ITS-G5 and Cellular-VCS in a Real-World Traffic Scenario Proceedings Article
In: IEEE Vehicular Technology Conference (VTC-Fall), Chicago, IL, US, 2018.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, performance, simulation, V2X communication
@inproceedings{Kuelmorgen:VTCFall:2018,
title = {Simulation-based Evaluation of ETSI ITS-G5 and Cellular-VCS in a Real-World Traffic Scenario},
author = {S. Kühlmorgen and P. Schmarger and A. Festag and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/8691011},
doi = {10.1109/VTCFall.2018.8691011},
year = {2018},
date = {2018-08-27},
booktitle = {IEEE Vehicular Technology Conference (VTC-Fall)},
address = {Chicago, IL, US},
abstract = {In recent years, two candidates for vehicular communications have evolved for the support of road safety and traffic efficiency applications. On the one hand, ad-hoc networks exist based on the ITS-G5/802.11p protocol stack, and on the other hand, there are cellular network infrastructures based on an extended LTE stack, which we refer to as Cellular-based Vehicular Communication Systems (Cellular-VCS). The most important extension of the classical LTE stack is a direct link among vehicles which is also called Device-to-Device (D2D) communication. Both approaches meet the requirements on vehicular communications but show technology-inherent mechanisms that result in different performances. ITS-G5 features a small latency at a small network load whereas Cellular-VCS promises a highly reliable packet transmission. One of the main difference of both approaches lies in the channel access which is random-based for ITS-G5 and centrally scheduled for Cellular-VCS. This contribution studies the performance of the two named technologies in a real-world road traffic scenario through comprehensive simulations. The simulation scenario makes use of real road traffic density measurements for modeling the mobility of the vehicles. Mixed network data traffic of periodically and event-based messages is generated through particular generation rules. The results prove that both technologies work stable at moderate road traffic conditions but have significant differences in the quantified communication parameters.},
keywords = {Cooperative ITS, Intelligent Transport Systems, performance, simulation, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
In recent years, two candidates for vehicular communications have evolved for the support of road safety and traffic efficiency applications. On the one hand, ad-hoc networks exist based on the ITS-G5/802.11p protocol stack, and on the other hand, there are cellular network infrastructures based on an extended LTE stack, which we refer to as Cellular-based Vehicular Communication Systems (Cellular-VCS). The most important extension of the classical LTE stack is a direct link among vehicles which is also called Device-to-Device (D2D) communication. Both approaches meet the requirements on vehicular communications but show technology-inherent mechanisms that result in different performances. ITS-G5 features a small latency at a small network load whereas Cellular-VCS promises a highly reliable packet transmission. One of the main difference of both approaches lies in the channel access which is random-based for ITS-G5 and centrally scheduled for Cellular-VCS. This contribution studies the performance of the two named technologies in a real-world road traffic scenario through comprehensive simulations. The simulation scenario makes use of real road traffic density measurements for modeling the mobility of the vehicles. Mixed network data traffic of periodically and event-based messages is generated through particular generation rules. The results prove that both technologies work stable at moderate road traffic conditions but have significant differences in the quantified communication parameters.
39.
Fritzsche, R.; Festag, A.
Location-Based Scheduling for Cellular V2V Systems in Highway Scenarios Proceedings Article
In: IEEE Vehicular Technology Conference (VTC-Spring), Porto, Portugal, 2018.
Abstract | Links | BibTeX | Tags: Cooperative ITS, Intelligent Transport Systems, optimization, V2X communication
@inproceedings{Fritzsche:VTC:2018,
title = {Location-Based Scheduling for Cellular V2V Systems in Highway Scenarios},
author = {R. Fritzsche and A. Festag},
url = {https://ieeexplore.ieee.org/document/8417744},
doi = {10.1109/VTCSpring.2018.8417744},
year = {2018},
date = {2018-06-03},
booktitle = {IEEE Vehicular Technology Conference (VTC-Spring)},
address = {Porto, Portugal},
abstract = {In intelligent transport systems (ITS), vehicular users broadcast messages with ego information such as position, speed, and other. For exchanging ITS messages directly among vehicles via cellular sidelink transmission, the base station assigns dedicated V2V radio resources for users in coverage. To improve spectral efficiency, the same radio resource can be simultaneously scheduled to multiple vehicles within a cell, e.g., based on a minimum vehicle distance. This distance can be determined by location information obtained from ITS messages. In this work, we introduce a framework for location-based scheduling, exposing basic relations among cell spectral efficiency, communication range and reliability. Based on the framework we show that an optimal scheduling distance exists, which maximizes the cell throughput by guaranteeing range and reliability constraints. The optimized distance can then be utilized by the base station scheduler, which benefits from a closed form solution for the outage probability, derived in this work. We validate that the proposed form with its simplifications achieves a similar performance compared with the optimal solution, obtained by Monte Carlo simulations.},
keywords = {Cooperative ITS, Intelligent Transport Systems, optimization, V2X communication},
pubstate = {published},
tppubtype = {inproceedings}
}
In intelligent transport systems (ITS), vehicular users broadcast messages with ego information such as position, speed, and other. For exchanging ITS messages directly among vehicles via cellular sidelink transmission, the base station assigns dedicated V2V radio resources for users in coverage. To improve spectral efficiency, the same radio resource can be simultaneously scheduled to multiple vehicles within a cell, e.g., based on a minimum vehicle distance. This distance can be determined by location information obtained from ITS messages. In this work, we introduce a framework for location-based scheduling, exposing basic relations among cell spectral efficiency, communication range and reliability. Based on the framework we show that an optimal scheduling distance exists, which maximizes the cell throughput by guaranteeing range and reliability constraints. The optimized distance can then be utilized by the base station scheduler, which benefits from a closed form solution for the outage probability, derived in this work. We validate that the proposed form with its simplifications achieves a similar performance compared with the optimal solution, obtained by Monte Carlo simulations.
40.
González, A.; Kühlmorgen, S.; Festag, A.; Fettweis, G.
Resource Allocation for Block-Based Multi-Carrier Systems Considering QoS Requirements Proceedings Article
In: IEEE Global Communications Conference (Globecom), Singapore, 2017.
Abstract | Links | BibTeX | Tags: optimization, wireless communication
@inproceedings{Gonzalez:GLOBECOM:2017,
title = {Resource Allocation for Block-Based Multi-Carrier Systems Considering QoS Requirements},
author = {A. González and S. Kühlmorgen and A. Festag and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/8254649},
doi = {10.1109/GLOCOM.2017.8254649},
year = {2017},
date = {2017-12-04},
urldate = {2018-01-15},
booktitle = {IEEE Global Communications Conference (Globecom)},
address = {Singapore},
abstract = {Future 5G and beyond mobile networks target at services with a high degree of heterogeneity in terms of their communication requirements. To meet these requirements, different PHY numerologies would provide a better performance; still, all services must be served by a single network technology. Generalized Frequency Division Multiplexing (GFDM) is a good candidate for PHY virtualization where the dimensions of the data block can be dynamically configured in time and frequency. Allocating these blocks in a common spectrum every scheduling period leads to a "packing" problem, in which the QoS demands of the data flows need to be acknowledged. In this paper we consider the optimization of the data block allocation as a Knapsack problem. We incorporate the flows' QoS demands by means of utility theory, where utility functions provide a metric of urgency for a flow to be scheduled and the data block to be allocated. For the resulting two-dimensional geometric Knapsack problem we propose a heuristic solution, assess different design options and evaluate the performance in terms of data rate and queuing delay.},
keywords = {optimization, wireless communication},
pubstate = {published},
tppubtype = {inproceedings}
}
Future 5G and beyond mobile networks target at services with a high degree of heterogeneity in terms of their communication requirements. To meet these requirements, different PHY numerologies would provide a better performance; still, all services must be served by a single network technology. Generalized Frequency Division Multiplexing (GFDM) is a good candidate for PHY virtualization where the dimensions of the data block can be dynamically configured in time and frequency. Allocating these blocks in a common spectrum every scheduling period leads to a "packing" problem, in which the QoS demands of the data flows need to be acknowledged. In this paper we consider the optimization of the data block allocation as a Knapsack problem. We incorporate the flows' QoS demands by means of utility theory, where utility functions provide a metric of urgency for a flow to be scheduled and the data block to be allocated. For the resulting two-dimensional geometric Knapsack problem we propose a heuristic solution, assess different design options and evaluate the performance in terms of data rate and queuing delay.