Publications
21.
Fritzsche, R.; Festag, A.
Reliability Maximization with Location-Based Scheduling for Cellular-V2X Communications in Highway Scenarios Inproceedings
In: IEEE 16th International Conference on Intelligent Transportation Systems Telecommunications (ITST), Lisbon, Portugal, 2018.
@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 = {},
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.
22.
Kühlmorgen, S.; Schmarger, P.; Festag, A.; Fettweis, G.
Simulation-based Evaluation of ETSI ITS-G5 and Cellular-VCS in a Real-World Traffic Scenario Inproceedings
In: IEEE Vehicular Technology Conference (VTC-Fall), Chicago, IL, US, 2018.
@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 = {},
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.
23.
Fritzsche, R.; Festag, A.
Location-Based Scheduling for Cellular V2V Systems in Highway Scenarios Inproceedings
In: IEEE Vehicular Technology Conference (VTC-Spring), Porto, Portugal, 2018.
@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 = {},
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.
24.
González, A.; Kühlmorgen, S.; Festag, A.; Fettweis, G.
Resource Allocation for Block-Based Multi-Carrier Systems Considering QoS Requirements Inproceedings
In: IEEE Global Communications Conference (Globecom), Singapore, 2017.
@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 = {},
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.
25.
Hung, S. C.; Zhang, X.; Festag, A.; Chen, K. C.; Fettweis, G.
Virtual Cells and Virtual Networks Enable Low-Latency Vehicle-to-Vehicle Communication Inproceedings
In: IEEE Global Communications Conference (Globecom), Singapore, 2017.
@inproceedings{Hung:GLOBECOM:2017,
title = {Virtual Cells and Virtual Networks Enable Low-Latency Vehicle-to-Vehicle Communication},
author = {S. C. Hung and X. Zhang and A. Festag and K. C. Chen and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/8254616},
doi = {10.1109/GLOCOM.2017.8254616},
year = {2017},
date = {2017-12-04},
urldate = {2018-01-15},
booktitle = {IEEE Global Communications Conference (Globecom)},
address = {Singapore},
abstract = {This paper presents a framework for pursuing lowlatency communication among V2V networks underlaying V2I networks. To achieve low-latency communication, solely relying on the improvement of the air-interface may not be enough. To cope with the highly dynamic environment of vehicular networks, a time dynamic optimization approach is proposed that improves the latency performance through not only optimization of spectrum resources but also by constraining the network switching rate. To further decrease the complexity of the time dynamic optimization problem, we convert the original problem to a deterministic optimization problem through the Lyapunov Optimization Theory. The proposed algorithm becomes a more suitable scheme for the vehicular network. Analytical results show that the proposed scheme can approach the best tradeoff between the latency performance and the network switching rate. Simulation results are provided to verify the proposed algorithm.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
This paper presents a framework for pursuing lowlatency communication among V2V networks underlaying V2I networks. To achieve low-latency communication, solely relying on the improvement of the air-interface may not be enough. To cope with the highly dynamic environment of vehicular networks, a time dynamic optimization approach is proposed that improves the latency performance through not only optimization of spectrum resources but also by constraining the network switching rate. To further decrease the complexity of the time dynamic optimization problem, we convert the original problem to a deterministic optimization problem through the Lyapunov Optimization Theory. The proposed algorithm becomes a more suitable scheme for the vehicular network. Analytical results show that the proposed scheme can approach the best tradeoff between the latency performance and the network switching rate. Simulation results are provided to verify the proposed algorithm.
26.
Zhang, D.; Festag, A.; Fettweis, G.
Performance of Generalized Frequency Division Multiplexing Based Physical Layer in Vehicular Communication Journal Article
In: IEEE Transactions on Vehicular Technology, vol. 66, no. 11, pp. 9809-9824, 2017.
@article{Zhang:TVT:2017,
title = {Performance of Generalized Frequency Division Multiplexing Based Physical Layer in Vehicular Communication},
author = {D. Zhang and A. Festag and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/7968507},
doi = {10.1109/TVT.2017.2723729},
year = {2017},
date = {2017-07-05},
urldate = {2017-07-05},
journal = {IEEE Transactions on Vehicular Technology},
volume = {66},
number = {11},
pages = {9809-9824},
abstract = {Vehicular communications enable information exchange among vehicles including the roadside infrastructure. This has led to applications to primarily increase road safety and traffic efficiency. Standardization efforts on vehicular communications are underway. The physical layer (PHY) is defined based on the IEEE 802.11 family of WiFi standards operating at the 5.9 GHz frequency band and on extensions of long-term evolution (LTE); in both cases orthogonal frequency division multiplexing (OFDM) is the waveform of choice. Since the typical environment of WiFi deployment is very different to the vehicular communication environment, it is a challenging task to adapt the WiFi-based PHY for providing reliable and real-time communications under highly time- and frequency-selective fading channels. In this paper, the employment of an alternative waveform termed generalized frequency division multiplexing (GFDM) for vehicular communication is investigated. Specifically, a GFDM-based packet design is proposed on the basis of the standard-compliant OFDM-based PHY configuration. On the receiver side, this paper focuses on developing synchronization, channel estimation, and equalization algorithms. The performance of the resulting GFDM-based PHY is verified and compared with the OFDM-based one by means of simulation. The obtained results demonstrate that the proposed GFDM-based PHY can utilize the time and frequency resources more efficiently, and outperform particularly under challenging channel conditions. Additionally, the low out-of-band emission of GFDM is a desirable feature for future multichannel operation (MCO) in vehicular communications.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Vehicular communications enable information exchange among vehicles including the roadside infrastructure. This has led to applications to primarily increase road safety and traffic efficiency. Standardization efforts on vehicular communications are underway. The physical layer (PHY) is defined based on the IEEE 802.11 family of WiFi standards operating at the 5.9 GHz frequency band and on extensions of long-term evolution (LTE); in both cases orthogonal frequency division multiplexing (OFDM) is the waveform of choice. Since the typical environment of WiFi deployment is very different to the vehicular communication environment, it is a challenging task to adapt the WiFi-based PHY for providing reliable and real-time communications under highly time- and frequency-selective fading channels. In this paper, the employment of an alternative waveform termed generalized frequency division multiplexing (GFDM) for vehicular communication is investigated. Specifically, a GFDM-based packet design is proposed on the basis of the standard-compliant OFDM-based PHY configuration. On the receiver side, this paper focuses on developing synchronization, channel estimation, and equalization algorithms. The performance of the resulting GFDM-based PHY is verified and compared with the OFDM-based one by means of simulation. The obtained results demonstrate that the proposed GFDM-based PHY can utilize the time and frequency resources more efficiently, and outperform particularly under challenging channel conditions. Additionally, the low out-of-band emission of GFDM is a desirable feature for future multichannel operation (MCO) in vehicular communications.
27.
Kühlmorgen, S.; González, A.; Festag, A.; Fettweis, G.
Improving Communication-based Intersection Safety by Cooperative Relaying with Joint Decoding Inproceedings
In: IEEE Intelligent Vehicles Symposium (IV), Redondo Beach, CA, USA, 2017.
@inproceedings{Kuehlmorgen:IV:2017,
title = {Improving Communication-based Intersection Safety by Cooperative Relaying with Joint Decoding},
author = {S. Kühlmorgen and A. González and A. Festag and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/7995796},
doi = {10.1109/IVS.2017.7995796},
year = {2017},
date = {2017-06-14},
urldate = {2017-07-31},
booktitle = {IEEE Intelligent Vehicles Symposium (IV)},
address = {Redondo Beach, CA, USA},
abstract = {Vehicular communications have a great potential to improve intersection safety and traffic efficiency. Achieving a high application performance is challenging due to the specific propagation conditions caused by buildings and obstacles found at urban intersections. Relying on the state-of-the-art solution for vehicular communication based on IEEE 802.11, we extend contention-based forwarding to distribute data packets via multiple paths and apply joint decoding on erroneous received data packets. We study the gain of cooperative relaying with joint decoding on the performance of collision avoidance applications in an intersection scenario. We could show that with our algorithm the awareness distance and reliability is increased up to 25m and 55, respectively, under poor channel conditions.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
Vehicular communications have a great potential to improve intersection safety and traffic efficiency. Achieving a high application performance is challenging due to the specific propagation conditions caused by buildings and obstacles found at urban intersections. Relying on the state-of-the-art solution for vehicular communication based on IEEE 802.11, we extend contention-based forwarding to distribute data packets via multiple paths and apply joint decoding on erroneous received data packets. We study the gain of cooperative relaying with joint decoding on the performance of collision avoidance applications in an intersection scenario. We could show that with our algorithm the awareness distance and reliability is increased up to 25m and 55, respectively, under poor channel conditions.
28.
Llatser, I.; Jornod, G.; Festag, A.; Mansolino, D.; Navarro, I.; Martinoli, A.
Simulation of Cooperative Automated Driving by Bidirectional Coupling of Vehicle and Network Simulators Inproceedings
In: IEEE Intelligent Vehicles Symposium (IV), Redondo Beach, CA, USA, 2017.
@inproceedings{Llatser:IV:2017,
title = {Simulation of Cooperative Automated Driving by Bidirectional Coupling of Vehicle and Network Simulators},
author = {I. Llatser and G. Jornod and A. Festag and D. Mansolino and I. Navarro and A. Martinoli},
url = {https://ieeexplore.ieee.org/document/7995979},
doi = {10.1109/IVS.2017.7995979},
year = {2017},
date = {2017-06-11},
urldate = {2017-07-31},
booktitle = {IEEE Intelligent Vehicles Symposium (IV)},
address = {Redondo Beach, CA, USA},
abstract = {The convergence of sensor-based vehicle automation and Inter-Vehicle Communication (IVC) will be a key to achieve the full automation of vehicles. In this paper we present a new method for the design and performance evaluation of Cooperative Automated Driving (CAD) systems, based on a bidirectional coupling of vehicle and network simulators (Webots and ns-3). The coupling exploits the comprehensive capabilities of the simulators at a reasonable computational complexity and allows simulating CAD systems with high accuracy. We demonstrate the capabilities of the simulation tool by a case study of convoy driving with automated vehicles using a fully distributed control algorithm and IVC. The study compares CAD-specific metrics (safety distance, headway, speed) for an ideal and a realistic communication channel. The simulation results underline the need of accurate modeling and give valuable insights for the design of CAD systems.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
The convergence of sensor-based vehicle automation and Inter-Vehicle Communication (IVC) will be a key to achieve the full automation of vehicles. In this paper we present a new method for the design and performance evaluation of Cooperative Automated Driving (CAD) systems, based on a bidirectional coupling of vehicle and network simulators (Webots and ns-3). The coupling exploits the comprehensive capabilities of the simulators at a reasonable computational complexity and allows simulating CAD systems with high accuracy. We demonstrate the capabilities of the simulation tool by a case study of convoy driving with automated vehicles using a fully distributed control algorithm and IVC. The study compares CAD-specific metrics (safety distance, headway, speed) for an ideal and a realistic communication channel. The simulation results underline the need of accurate modeling and give valuable insights for the design of CAD systems.
29.
Zhang, X.; Festag, A.; Fettweis, G.
Linear Precoder Design with Imperfect CSI in Underlay Device-to-Device Communication for a Vehicular Platooning Scenario Inproceedings
In: IEEE Vehicular Technology Conference (VTC-Spring), Sydney, NSW, Australia, 2017.
@inproceedings{Zhang:VTCSpring:2017,
title = {Linear Precoder Design with Imperfect CSI in Underlay Device-to-Device Communication for a Vehicular Platooning Scenario},
author = {X. Zhang and A. Festag and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/8108249},
doi = {10.1109/VTCSpring.2017.8108249},
year = {2017},
date = {2017-06-04},
urldate = {2017-11-16},
booktitle = {IEEE Vehicular Technology Conference (VTC-Spring)},
address = {Sydney, NSW, Australia},
abstract = {This paper proposes a novel design for linear precoder in underlay Device-to-Device (D2D) communication using cellular network, specifically for a use case with vehicle-to-vehicle communication and platooning. To increase the communication reliability, we develop an optimization algorithm for precoder that takes into account the outage probability when channel state information (CSI) is only partially available at devices and transmission could be in outage. The algorithm aims at maximizing the sum throughput over each transmission link received at one device, while constraining the interference caused by the transmit power from each device to the cellular network. Due to the intractable form of outage probability, an extended Markov Inequality is used to transform the problem into an upper-bound expression. A two-step alternating algorithm is then adapted to solve the multi- variable optimization. The proposed algorithm is compared with other state-of-the-art technologies in the field of vehicular communication for achieving high throughput. Simulation results show that our proposed algorithm outperforms the current techniques and achieves higher average throughput with extremely low outage probability, thus enables reliable vehicle- to-vehicle communication for platooning in a D2D underlay setting.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
This paper proposes a novel design for linear precoder in underlay Device-to-Device (D2D) communication using cellular network, specifically for a use case with vehicle-to-vehicle communication and platooning. To increase the communication reliability, we develop an optimization algorithm for precoder that takes into account the outage probability when channel state information (CSI) is only partially available at devices and transmission could be in outage. The algorithm aims at maximizing the sum throughput over each transmission link received at one device, while constraining the interference caused by the transmit power from each device to the cellular network. Due to the intractable form of outage probability, an extended Markov Inequality is used to transform the problem into an upper-bound expression. A two-step alternating algorithm is then adapted to solve the multi- variable optimization. The proposed algorithm is compared with other state-of-the-art technologies in the field of vehicular communication for achieving high throughput. Simulation results show that our proposed algorithm outperforms the current techniques and achieves higher average throughput with extremely low outage probability, thus enables reliable vehicle- to-vehicle communication for platooning in a D2D underlay setting.
30.
Kühlmorgen, S.; Festag, A.; Fettweis, G.
Evaluation of Multi-hop Packet Prioritization for Decentralized Congestion Control in VANETs Inproceedings
In: IEEE Wireless Communications and Networking Conference (WCNC), San Francisco, CA, USA, 2017.
@inproceedings{Kuehlmorgen:WCNC:2017,
title = {Evaluation of Multi-hop Packet Prioritization for Decentralized Congestion Control in VANETs},
author = {S. Kühlmorgen and A. Festag and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/7925899},
doi = {10.1109/WCNC.2017.7925899},
year = {2017},
date = {2017-03-19},
urldate = {2017-05-11},
booktitle = {IEEE Wireless Communications and Networking Conference (WCNC)},
address = {San Francisco, CA, USA},
abstract = {Decentralized congestion control (DCC) in ITS-G5 based vehicular ad hoc networks ensures that the requirements of safety and traffic efficiency applications are met even under high vehicle density and channel load conditions. In European standardization, a "gatekeeper" on top of the ITS-G5 MAC sub-layer is being considered that controls a node's packet rate as a function of the channel load. This paper studies the performance of the gatekeeper with packet prioritization and an adaptive linear control algorithm. The simulation results indicate that the gatekeeper with priority queuing (PQ) can effectively handle different packet priorities for multi-hop packets. Our gatekeeper-specific enhancements of the forwarding algorithm yield performance improvements in terms of reliability and latency compared to the plain DCC approach. Finally, we discuss the issue of packet starvation caused by the gatekeeper's PQ scheme that affects the performance of lower-priority packets.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
Decentralized congestion control (DCC) in ITS-G5 based vehicular ad hoc networks ensures that the requirements of safety and traffic efficiency applications are met even under high vehicle density and channel load conditions. In European standardization, a "gatekeeper" on top of the ITS-G5 MAC sub-layer is being considered that controls a node's packet rate as a function of the channel load. This paper studies the performance of the gatekeeper with packet prioritization and an adaptive linear control algorithm. The simulation results indicate that the gatekeeper with priority queuing (PQ) can effectively handle different packet priorities for multi-hop packets. Our gatekeeper-specific enhancements of the forwarding algorithm yield performance improvements in terms of reliability and latency compared to the plain DCC approach. Finally, we discuss the issue of packet starvation caused by the gatekeeper's PQ scheme that affects the performance of lower-priority packets.
31.
Acatech,
Neue Autombilität - Automatisierter Strassenverkehr der Zukunft Miscellaneous
Acactech Studie, 2016.
@misc{Acatech:AutoMobilitaet:2016,
title = {Neue Autombilität - Automatisierter Strassenverkehr der Zukunft},
author = {Acatech},
url = {https://www.acatech.de/publikation/neue-automobilitaet-automatisierter-strassenverkehr-der-zukunft/download-pdf},
year = {2016},
date = {2016-12-06},
urldate = {2016-12-06},
abstract = {Die 40 Institutionen umfassende Projektgruppe Neue autoMobilität aus Wissenschaft, Wirtschaft und Gesellschaft beschreibt in der vorliegenden acatech Studie den automatisierten Straßenverkehr der Zukunft. Längerfristig ist dieser ein Mischverkehr aus Fahrzeugen mit unterschiedlichen Automatisie- rungsstufen. Dabei ist die Interaktion von automati- sierten und nicht automatisierten Fahrzeugen ebenso zentral wie der Umgang mit nicht motorisierten Verkehrsteilnehmenden. Die Entwicklung bis 2030 wird stufenweise erfolgen. Im niedrigen Geschwindigkeitsbereich, zum Beispiel bei der automatisierten Parkplatzsuche (Valet Parking), kann fahrerloses Fahren bereits 2020 serienreif sein.},
howpublished = {Acactech Studie},
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Die 40 Institutionen umfassende Projektgruppe Neue autoMobilität aus Wissenschaft, Wirtschaft und Gesellschaft beschreibt in der vorliegenden acatech Studie den automatisierten Straßenverkehr der Zukunft. Längerfristig ist dieser ein Mischverkehr aus Fahrzeugen mit unterschiedlichen Automatisie- rungsstufen. Dabei ist die Interaktion von automati- sierten und nicht automatisierten Fahrzeugen ebenso zentral wie der Umgang mit nicht motorisierten Verkehrsteilnehmenden. Die Entwicklung bis 2030 wird stufenweise erfolgen. Im niedrigen Geschwindigkeitsbereich, zum Beispiel bei der automatisierten Parkplatzsuche (Valet Parking), kann fahrerloses Fahren bereits 2020 serienreif sein.
32.
Rehme, M.; Festag, A.; Krause, J.
Kommunikationstechnologien der Mobilität 2025+ - Communication technologies for mobility 2025+ Inproceedings
In: VDE Congress 2016 - Internet der Dinge, Mannheim, Germany, 2016.
@inproceedings{Rehme:VDECongress:2016,
title = {Kommunikationstechnologien der Mobilität 2025+ - Communication technologies for mobility 2025+},
author = {M. Rehme and A. Festag and J. Krause},
url = {https://festag-net.de/wp-content/uploads/2016_Rehme_VDECongress.pdf},
year = {2016},
date = {2016-11-07},
urldate = {2016-11-07},
booktitle = {VDE Congress 2016 - Internet der Dinge},
address = {Mannheim, Germany},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
33.
Boban, M.; Festag, A.
Service-actuated Multi-channel Operation for Vehicular Communications Journal Article
In: Elsevir Computer Communications, Special Issue on Multi-radio, Multi-technology, Multi-system Vehicular Communications, vol. 93, pp. 17-26, 2016, ISSN: 0140-3664.
@article{Boban:Elsevir:2016,
title = {Service-actuated Multi-channel Operation for Vehicular Communications},
author = {M. Boban and A. Festag},
url = {https://www.sciencedirect.com/science/article/abs/pii/S0140366416302201},
doi = {10.1016/j.comcom.2016.05.014},
issn = {0140-3664},
year = {2016},
date = {2016-11-01},
urldate = {2016-11-01},
journal = {Elsevir Computer Communications, Special Issue on Multi-radio, Multi-technology, Multi-system Vehicular Communications},
volume = {93},
pages = {17-26},
abstract = {We present a novel approach for multi-channel operation (MCO) in vehicular communication systems, which allows for efficient utilization of the available bandwidth by asynchronous channel switching and enables dynamic service provisioning and usage by means of service advertisements. The proposed solution – Service-Actuated Multi-Channel Operation (SAMCO) – provides a logic that controls the prioritization of services and the timing of channel switching. It takes into account users preferences to decide on the consumption of a particular service if several concurrent services are available. SAMCO employs a novel channel load estimation scheme that, in addition to measuring the load on the channel at the physical layer, exploits the information contained in service advertisements. We perform simulations and use platooning as an example of a service with particularly stringent requirements to show that SAMCO can support service prioritization, continuity of service for high-priority services, and graceful degradation for low-priority services. Furthermore, by limiting the admission to services in high load scenarios, we show that SAMCO effectively controls the channel load and thereby complements congestion control mechanisms. Finally, we discuss the extensions needed in currently standardized solutions to implement SAMCO.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We present a novel approach for multi-channel operation (MCO) in vehicular communication systems, which allows for efficient utilization of the available bandwidth by asynchronous channel switching and enables dynamic service provisioning and usage by means of service advertisements. The proposed solution – Service-Actuated Multi-Channel Operation (SAMCO) – provides a logic that controls the prioritization of services and the timing of channel switching. It takes into account users preferences to decide on the consumption of a particular service if several concurrent services are available. SAMCO employs a novel channel load estimation scheme that, in addition to measuring the load on the channel at the physical layer, exploits the information contained in service advertisements. We perform simulations and use platooning as an example of a service with particularly stringent requirements to show that SAMCO can support service prioritization, continuity of service for high-priority services, and graceful degradation for low-priority services. Furthermore, by limiting the admission to services in high load scenarios, we show that SAMCO effectively controls the channel load and thereby complements congestion control mechanisms. Finally, we discuss the extensions needed in currently standardized solutions to implement SAMCO.
34.
Leinmüller, T.; Spaanderman, P.; Festag, A.
Next Steps for Multi-channel Operation in EU V2X Systems Inproceedings
In: 23rd ITS World Congress and Exhibition, Melbourne, Australia, 2016.
@inproceedings{Leinmueller:ITSWC:2016,
title = {Next Steps for Multi-channel Operation in EU V2X Systems},
author = {T. Leinmüller and P. Spaanderman and A. Festag},
url = {https://www.itsworldcongress2016.com},
year = {2016},
date = {2016-10-10},
urldate = {2016-10-10},
booktitle = {23rd ITS World Congress and Exhibition},
address = {Melbourne, Australia},
abstract = {Cooperative Intelligent Transport Systems (C-ITS) operating in the 5 GHz band in Europe is expected to use only a single communication channel during initial deployment phase. The initial deployment is focused on a limited set of applications assuming a rather small equipment rate of vehicles and road side stations. Current efforts spent on future C-ITS application research indicate considerable growth of C-ITS penetration in following years. The increasing C-ITS penetration rate and the introduction of novel applications will result in growing demand of communication bandwidth that can be addressed by utilizing multiple radio communication channels in parallel. This paper discusses requirements for multi-channel operation (MCO) in European C-ITS, analyzes boundary conditions in the designated frequency bands, presents a concept for offloading and backloading information from congested communication channels, and describes extensions to the GeoNetworking protocol to support MCO.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
Cooperative Intelligent Transport Systems (C-ITS) operating in the 5 GHz band in Europe is expected to use only a single communication channel during initial deployment phase. The initial deployment is focused on a limited set of applications assuming a rather small equipment rate of vehicles and road side stations. Current efforts spent on future C-ITS application research indicate considerable growth of C-ITS penetration in following years. The increasing C-ITS penetration rate and the introduction of novel applications will result in growing demand of communication bandwidth that can be addressed by utilizing multiple radio communication channels in parallel. This paper discusses requirements for multi-channel operation (MCO) in European C-ITS, analyzes boundary conditions in the designated frequency bands, presents a concept for offloading and backloading information from congested communication channels, and describes extensions to the GeoNetworking protocol to support MCO.
35.
Festag, A.; Kühlmorgen, S.; Maslekar, N.
Decentralized Congestion Control for Multi-hop Vehicular Communication Inproceedings
In: 23rd ITS World Congress and Exhibition, Melbourne, Australia, 2016.
@inproceedings{Festag:ITSWC:2016,
title = {Decentralized Congestion Control for Multi-hop Vehicular Communication},
author = {A. Festag and S. Kühlmorgen and N. Maslekar},
url = {https://www.itsworldcongress2016.com},
year = {2016},
date = {2016-10-10},
urldate = {2016-10-10},
booktitle = {23rd ITS World Congress and Exhibition},
address = {Melbourne, Australia},
abstract = {WiFi-based vehicular communication systems, such as DSRC in the US and C-ITS in Europe, suffer from large delays and high packet losses in scenarios with a dense distribution of nodes and high data load, which can result in system instability and degraded safety application performance. To ensure a stable system and fair share of resources among vehicles, a decentralized congestion control (DCC) function limits the data that is generated by a network node depending on the measured channel load. In a vehicular ad hoc network with multi-hop communication, DCC need to control the data packets that are locally generated by the node as well as forwarded data packets. This paper gives an overview of the cross-layer DCC framework for the European C-ITS, presents results of a simulation-based performance evaluation of DCC and analyzes the impact of DCC on forwarding algorithms of the ad hoc networking protocol.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
WiFi-based vehicular communication systems, such as DSRC in the US and C-ITS in Europe, suffer from large delays and high packet losses in scenarios with a dense distribution of nodes and high data load, which can result in system instability and degraded safety application performance. To ensure a stable system and fair share of resources among vehicles, a decentralized congestion control (DCC) function limits the data that is generated by a network node depending on the measured channel load. In a vehicular ad hoc network with multi-hop communication, DCC need to control the data packets that are locally generated by the node as well as forwarded data packets. This paper gives an overview of the cross-layer DCC framework for the European C-ITS, presents results of a simulation-based performance evaluation of DCC and analyzes the impact of DCC on forwarding algorithms of the ad hoc networking protocol.
36.
Hung, S. C.; Zhang, X.; Festag, A.; Chen, K. C.; Fettweis, G.
An Efficient Radio Resource Re-Allocation Scheme for Delay Guaranteed Vehicle-to-Vehicle Networks Inproceedings
In: IEEE Vehicular Technology Conference (VTC-Fall), Montreal, QC, Canada, 2016.
@inproceedings{Hung:VTCFall:2016,
title = {An Efficient Radio Resource Re-Allocation Scheme for Delay Guaranteed 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/7880896},
doi = {10.1109/VTCFall.2016.7880896},
year = {2016},
date = {2016-09-18},
urldate = {2017-03-20},
booktitle = {IEEE Vehicular Technology Conference (VTC-Fall)},
address = {Montreal, QC, Canada},
abstract = {To achieve low delay for vehicular communication in cellular networks, the use of direct device-to-device (D2D) communication among vehicles is regarded as a key functional requirement. When D2D users share the spectrum with regular cellular users (D2D underlay), resource allocation schemes assure the coexistence between D2D and cellular users. Due to the high mobility of the vehicles, the resources need to be reallocated, but frequent updates cause high signaling overhead and degrade the delay performance. In this paper, we present a radio resource re-allocation scheme for vehicular D2D users in a platoon scenario. The scheme reduces the re-allocation rate and gives delay guarantees for each vehicle. With the help of Lyapunov optimization, a closed form of the upper delay bound and resource re-allocation rate is also derived. The simulation results show that the proposed scheme can provide an delay upper bound and simultaneously minimizes the resource re-allocation rate.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
To achieve low delay for vehicular communication in cellular networks, the use of direct device-to-device (D2D) communication among vehicles is regarded as a key functional requirement. When D2D users share the spectrum with regular cellular users (D2D underlay), resource allocation schemes assure the coexistence between D2D and cellular users. Due to the high mobility of the vehicles, the resources need to be reallocated, but frequent updates cause high signaling overhead and degrade the delay performance. In this paper, we present a radio resource re-allocation scheme for vehicular D2D users in a platoon scenario. The scheme reduces the re-allocation rate and gives delay guarantees for each vehicle. With the help of Lyapunov optimization, a closed form of the upper delay bound and resource re-allocation rate is also derived. The simulation results show that the proposed scheme can provide an delay upper bound and simultaneously minimizes the resource re-allocation rate.
37.
Kühlmorgen, S.; Festag, A.; Fettweis, G.
Impact of Decentralized Congestion Control on Contention-based Forwarding in VANETs Inproceedings
In: IEEE International Symposium on A World of Wireless, Mobile and Multimedia Networks (WoWMoM), Coimbra, Portugal, 2016.
@inproceedings{Kuehlmorgen:WoWMoM:2016,
title = {Impact of Decentralized Congestion Control on Contention-based Forwarding in VANETs},
author = {S. Kühlmorgen and A. Festag and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/7523572},
doi = {10.1109/WoWMoM.2016.7523572},
year = {2016},
date = {2016-06-21},
urldate = {2016-07-28},
booktitle = {IEEE International Symposium on A World of Wireless, Mobile and Multimedia Networks (WoWMoM)},
address = {Coimbra, Portugal},
abstract = {Vehicular ad hoc networks based on IEEE 802.11 OCB suffer from channel congestion, which will be critical for safety applications when the channel becomes saturated. Therefore, decentralized congestion control (DCC) is needed that keeps the channel load under a pre-defined threshold. In the European system for vehicular communication, a DCC-gatekeeper has been inserted into the protocol stack that reduces the data traffic generated or forwarded by the vehicle. This DCC-gatekeeper affects the functionality of the contention-based forwarding (CBF) and degrades its performance. In this paper we evaluate the performance of CBF under congestion-free and saturated channel conditions for several protocol variants: DCF, EDCA and DCC-gatekeeper. The results show that the standard DCC-gatekeeper hampers the functionality of CBF even for small node densities. We enhance the DCC-gatekeeper-based approach to overcome this issue and evaluate the protocol variants in terms of reliability, latency and channel load in a freeway scenario with realistic trace-based mobility.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
Vehicular ad hoc networks based on IEEE 802.11 OCB suffer from channel congestion, which will be critical for safety applications when the channel becomes saturated. Therefore, decentralized congestion control (DCC) is needed that keeps the channel load under a pre-defined threshold. In the European system for vehicular communication, a DCC-gatekeeper has been inserted into the protocol stack that reduces the data traffic generated or forwarded by the vehicle. This DCC-gatekeeper affects the functionality of the contention-based forwarding (CBF) and degrades its performance. In this paper we evaluate the performance of CBF under congestion-free and saturated channel conditions for several protocol variants: DCF, EDCA and DCC-gatekeeper. The results show that the standard DCC-gatekeeper hampers the functionality of CBF even for small node densities. We enhance the DCC-gatekeeper-based approach to overcome this issue and evaluate the protocol variants in terms of reliability, latency and channel load in a freeway scenario with realistic trace-based mobility.
38.
Tervo, V.; He, X.; Zhou, X.; Komulainen, P.; Kühlmorgen, S.; Wolf, A.; Festag, A.
An Error Rate Model of Relay Communications with Lossy Forwarding and Joint Decoding Inproceedings
In: IEEE International Conference on Communications Workshops (ICC), Kuala Lumpur, Malaysia, 2016.
@inproceedings{Tervo:ICC:2016,
title = {An Error Rate Model of Relay Communications with Lossy Forwarding and Joint Decoding},
author = {V. Tervo and X. He and X. Zhou and P. Komulainen and S. Kühlmorgen and A. Wolf and A. Festag},
url = {https://ieeexplore.ieee.org/abstract/document/7503841},
doi = {10.1109/ICCW.2016.7503841},
year = {2016},
date = {2016-05-23},
urldate = {2016-07-07},
booktitle = {IEEE International Conference on Communications Workshops (ICC)},
address = {Kuala Lumpur, Malaysia},
abstract = {This paper presents a link quality model for a wireless communication system with distributed turbo coding and lossy forwarding. The model maps the signal-to-interference-plus-noise ratio (SINR) of packet copies received from different links to a mutual information parameter and, in a second stage, converts it to a block error rate. We present the design and foundation of the model and validate its accuracy for different modulation and coding schemes over additive white Gaussian noise (AWGN) channels. The model accurately predicts the link-level performance at a low computational complexity and can be therefore used as an physical layer (PHY) abstraction for the computationally-intensive, simulation-based performance evaluation of various functionalities at higher protocol layers or at the system level. In order to illustrate the usage of the proposed model, we show the integration of the model into a protocol level simulator assessing the performance improvements of lossy forwarding and joint decoding.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
This paper presents a link quality model for a wireless communication system with distributed turbo coding and lossy forwarding. The model maps the signal-to-interference-plus-noise ratio (SINR) of packet copies received from different links to a mutual information parameter and, in a second stage, converts it to a block error rate. We present the design and foundation of the model and validate its accuracy for different modulation and coding schemes over additive white Gaussian noise (AWGN) channels. The model accurately predicts the link-level performance at a low computational complexity and can be therefore used as an physical layer (PHY) abstraction for the computationally-intensive, simulation-based performance evaluation of various functionalities at higher protocol layers or at the system level. In order to illustrate the usage of the proposed model, we show the integration of the model into a protocol level simulator assessing the performance improvements of lossy forwarding and joint decoding.
39.
Llatser, I.; Festag, A.; Fettweis, G.
Vehicular Communication Performance in Convoys of Automated Vehicles Inproceedings
In: IEEE International Conference on Communications (ICC), Kuala Lumpur, Malaysia, 2016.
@inproceedings{Llatser:ICC:2016,
title = {Vehicular Communication Performance in Convoys of Automated Vehicles},
author = {I. Llatser and A. Festag and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/7510772},
doi = {10.1109/ICC.2016.7510772},
year = {2016},
date = {2016-05-22},
urldate = {2016-07-14},
booktitle = {IEEE International Conference on Communications (ICC)},
address = {Kuala Lumpur, Malaysia},
abstract = {The combination of automated driving and Inter-Vehicle Communication (IVC) allows automated vehicles to drive cooperatively, thereby greatly enhancing their safety and traffic efficiency. Convoys are groups of automated vehicles which keep a multi-lane formation with decentralized control supported by IVC. The vehicle control algorithm of convoy vehicles requires up-to-date information about the neighbor vehicle dynamics; fast and efficient convoy communications enable the cooperative maneuvering of the automated vehicles. For this reason, we evaluate IVC in convoys of automated vehicles by defining performance metrics which quantify the reliability, latency and data age of convoy communications. Our results explore the trade-off between the convoy message frequency and the communication performance; whereas a high message frequency results in a higher number of lost messages and delay due to channel congestion, a low message frequency yields a higher data age of the information available to the vehicle controller. As a result, convoy algorithm designers should choose carefully the optimal value for the convoy message frequency as a function of the required communication performance and the convoy size.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
The combination of automated driving and Inter-Vehicle Communication (IVC) allows automated vehicles to drive cooperatively, thereby greatly enhancing their safety and traffic efficiency. Convoys are groups of automated vehicles which keep a multi-lane formation with decentralized control supported by IVC. The vehicle control algorithm of convoy vehicles requires up-to-date information about the neighbor vehicle dynamics; fast and efficient convoy communications enable the cooperative maneuvering of the automated vehicles. For this reason, we evaluate IVC in convoys of automated vehicles by defining performance metrics which quantify the reliability, latency and data age of convoy communications. Our results explore the trade-off between the convoy message frequency and the communication performance; whereas a high message frequency results in a higher number of lost messages and delay due to channel congestion, a low message frequency yields a higher data age of the information available to the vehicle controller. As a result, convoy algorithm designers should choose carefully the optimal value for the convoy message frequency as a function of the required communication performance and the convoy size.
40.
Kühlmorgen, S.; Festag, A.; Fettweis, G.
Exploiting Distributed Source Coding for Multi-hop Routing in Wireless Ad Hoc Network Inproceedings
In: IEEE Vehicular Technology Conference (VTC-Spring), Nanjing, China, 2016.
@inproceedings{Kuehlmorgen:VTCSpring:2016,
title = {Exploiting Distributed Source Coding for Multi-hop Routing in Wireless Ad Hoc Network},
author = {S. Kühlmorgen and A. Festag and G. Fettweis},
url = {https://ieeexplore.ieee.org/document/7504244},
doi = {10.1109/VTCSpring.2016.7504244},
year = {2016},
date = {2016-05-15},
urldate = {2016-07-07},
booktitle = {IEEE Vehicular Technology Conference (VTC-Spring)},
address = {Nanjing, China},
abstract = {This paper presents a routing algorithm for wireless multi-hop ad hoc networks, which applies distributed source coding (DSC) and multi-path transport of data packets. DSC enables the relay nodes to efficiently encode the packets and helps the destination node to correctly decode the information from multiple erroneous copies of the same packet received via different paths. While in conventional communication systems packets with bit errors are discarded, in our design the relays are allowed to forward erroneous packets. In order to exploit DSC for ad hoc routing, we extend contention-based geographical forwarding (CBGF) to support multi-path packet transport and enable the joint decoder to recover transmission errors. Under harsh wireless conditions, the approach promises performance gains compared to the case without joint decoding. In order to evaluate the performance of CBGF, we define an evaluation framework that models the erroneous forwarding and joint decoding by an abstraction of the physical transmission. We assess the performance by simulations for a simple scenario with static nodes in terms of packet success ratio, end-to-end delay, and data traffic overhead, and compare the results with the baseline CBGF scheme without DSC-specific extensions and joint decoding.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
This paper presents a routing algorithm for wireless multi-hop ad hoc networks, which applies distributed source coding (DSC) and multi-path transport of data packets. DSC enables the relay nodes to efficiently encode the packets and helps the destination node to correctly decode the information from multiple erroneous copies of the same packet received via different paths. While in conventional communication systems packets with bit errors are discarded, in our design the relays are allowed to forward erroneous packets. In order to exploit DSC for ad hoc routing, we extend contention-based geographical forwarding (CBGF) to support multi-path packet transport and enable the joint decoder to recover transmission errors. Under harsh wireless conditions, the approach promises performance gains compared to the case without joint decoding. In order to evaluate the performance of CBGF, we define an evaluation framework that models the erroneous forwarding and joint decoding by an abstraction of the physical transmission. We assess the performance by simulations for a simple scenario with static nodes in terms of packet success ratio, end-to-end delay, and data traffic overhead, and compare the results with the baseline CBGF scheme without DSC-specific extensions and joint decoding.