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This Deliverable 6.2 of the TransAID project presents and evaluates the simulation results obtained for the scenarios considered during the project's first and second iterations. To this end, driver- and AV-models designed in WP3, traffic management procedures developed in WP4, and V2X communication protocols and models from WP5 were implemented within the iTETRIS simulation framework. Previous main results from Deliverable 4.2, where baseline and traffic management measures without V2X communication were compared, have been confirmed. While not all TransAID scenarios' traffic KPIs were affected, the realistic simulation of V2X communication has shown a discernible impact on some of them, which makes it an indispensable modelling aspect for a realistic performance evaluation of V2X traffic scenarios. Flaws of the first iteration's traffic management algorithms concerning wireless V2X communication and the accompanying possibility of packet loss were identified and have been addressed during the project's second iteration. Finally, lessons learned while working on these simulation results and assessments have additionally been described in the form of recommendations for the real-world prototype to be developed in WP7. We conclude that all results obtained for all scenarios when employing ideal communication confirmed the statistical trends of the results from the original TM scenarios as reported in Deliverable 4.2 where no V2X communication was considered. Furthermore, the performance evaluation of the considered scenarios and parameter combinations has shown the following, which held true in both the first and second iterations: (1) The realistic simulation of V2X communication has an impact on traffic scenarios, which makes them indispensable for a realistic performance evaluation of V2X traffic scenarios. (2) Traffic management algorithms need to account for sporadic packet loss of various message types in some way. (3) Although important, the realistic modelling and simulation of V2X communication also induces a significant computational overhead. Thus, from a general perspective, a trade-off between computation time and degree of realism should be considered.

This deliverable is a direct successor of Deliverable 7.1, which has introduced all vehicles, test tracks, used hardware, and proposed system architectures of the different used components. D7.1 has also introduced several system requirements for each component and for each use case described in D2.1, which must be implemented. D7.2 shows the system architecture implementation for the different components of the infrastructure part as well as for the vehicle part. It is shown how both parts communicate in the real-world following D5.2 by presenting the finally used ASN.1 message definitions (in the Annex) and details about the communication software. In the project, real-world implementations have been performed at four partners. UMH was responsible for setting up the communication software required in all implementations. DLR assembled all use cases in several scenarios on the test track located in Peine-Eddesse in northern Germany. Dynniq implemented a C-ITS based highway merging as specified in use case 2.1 on public roads on the highway A13 in The Netherlands. HMETC finally took a closer look at ToC/MRM distribution in urban areas as specified in the combined use case 4.1-5 on a test track located in Griesheim, Germany. Besides the implementation, feasibility assessments of all TransAID measures have been performed. For this, each use case has been divided into test scenarios, which have been implemented in the real-world prototypes, demonstrated and assessed. Each test scenario is linked to related requirements set up in D7.1. During the feasibility assessment, the compliance with all requirements has been checked by project partner HMETC, who is taking the role of an OEM here. In addition, the overall "look and feel" of the prototype and the performance in each test scenario has been rated and described. In summary, nearly all requirements were fully met. Only in few cases the implementation deviates from the earlier requirement specification, sometimes due to new findings in the project, sometimes as not all implementations could be showcased due to the COVID-19 pandemic. Altogether, it could be shown that the TransAID measures can be put into real-world to help future automated vehicles to better cope with possible threats and to gain higher performance on the road. Nevertheless, further research is required to bring the measures to a higher Technology Readiness Level, up to series production. This is especially true for HMI design for vehicles and VMS (as this was not in scope of the project), vehicle automation behaviour in case of ToCs and MRMs, and I2V-MCM deconflicting.

5G offers high flexibility at the radio, transport and core networks to support various services of critical verticals such as connected and automated driving. At the Radio Access Network (RAN), 5G defines a New Radio (NR). 5G NR utilizes different subcarrier spacing, slot durations, modulations and channel coding schemes. This flexibility offers the possibility to support automotive services with different and demanding requirements, such as Advanced Driver-Assistance System (ADAS), cooperative driving, and remote driving. Previous studies showed that 5G NR can be configured to achieve latencies below 2 ms. However, existing studies are generally restricted to scenarios with a limited number of users and unlimited bandwidth. Therefore, it is important to analyze whether 5G NR can effectively support these services as the network scales under limited spectrum allocations. This study advances the current state of the art to demonstrate that the capability of 5G NR RAN to support advanced V2X services depends on the RAN configuration (subcarrier spacing, slot duration and error protection) and network load UMH work was supported in part by the Spanish Ministry of Science and Innovation (MCI), AEI and FEDER funds under Project TEC2017-88612-R, and the Ministry of Universities (IJC2018-036862-I), and the Generalitat Valenciana

The objective of the TransAID (Transition Areas for Infrastructure-Assisted Driving) project is to deal with situations that cooperative and automated vehicles (CAV) might face when they are approaching to traffic conditions or zones that their automated systems are not able to handle by themselves. In those cases, the driver will be required to take control of the vehicle; this is the so-called Transition of Control (ToC). TransAID develops and demonstrates traffic management procedures and protocols to increase the overall traffic safety and efficiency specially at transition areas (i.e. zones where ToCs should take place) considering the coexistence of CAVs,autonomous vehicles (AVs), cooperative vehicles (CVs) and legacy vehicles (LV). TransAID measures require the use of communications between vehicles (V2V), and between vehicles and the road infrastructure (V2I) which are mainly used to gather information about the traffic stream through cooperative sensing and to support in the coordination of the vehicles maneuvers through cooperative maneuvers. In this context, this document shows the sensor devices and techniques to fuse their data that are being developed in TransAID. This includes techniques implemented at camera-equipped infrastructures that are able to detect, create bounding boxes and uniquely track objects using optical flow, and at the vehicle employing a hybrid sensor fusion strategy which contains a low-level LIDAR fusion module, that transforms the sensor data of multiple laser scanners into a common coordinate system, and an object-level fusion module, that fuses in-vehicle sensor data with data coming from neighbouringvehicles. The document also shows the cooperative techniques that are being designed to enable the Collective Perception Service (CPS) in line with ETSI. The ETSI's CPS entails the continuous exchange of Collective Perception Messages (CPM) that include a logic representation of the objects detected by the sensors and which are useful to improve the vehicles' and the infrastructure's perception of the driving environment. A key aspect for the efficient execution of the CPS is the definition of appropriate generation rules for the transmission of the CPMs, i.e. how often they are transmittedand what information do they include. This document includes a comprehensive analysis of the effect on the communications performance and information awareness of different CPM generation rules that are being considered in ETSI. The conducted analysis has shown that there is a trade-off between perception capabilities and communications performance/scalability: vehicles detecting the same object(s) and including them in their CPMs create redundant detection which can help improve the perception capabilities but generate higher channel load levels and therefore impact the performance of V2X networks. In the framework of TransAID, advanced policies have been proposed to further optimize the CPM, both its content and transmission triggering conditions, in order to achieve the necessary levels of redundancy and minimize the impact of the implementation of CPM in the stability and scalability of future V2X networks. In particular, four different methods have been designed: a) the look ahead mechanism that reduces the number of CPM transmitted with a small number of objects by the prediction of objects that will need to be transmitted in a near future; b) the redundancy mitigation mechanism that reduces the size of the CPMs and thus increases reliability by limiting the transmission of objects that have been recently transmitted by a neighbour vehicle and c) two different proposals for the combination of previous methods that enhance the performance of collective perception. In addition, this document investigates existing cooperative driving mechanisms, and specially the ETSI approach on manoeuvre coordination. The ETSI's Manoeuvre Coordination Service (MCS) is defining new concepts and messages which can be used to coordinate manoeuvres between vehicles. TransAID is actively participating in this process, e.g., by means of the definition of the Manoeuvre Coordination Message (MCM) and extendingthe role of the infrastructure to support the vehicles' manoeuvres coordination under certain scenarios and conditions. In this context, this document presents the message flow for the set of services that are being consideredin TransAID. First, this documenthas analysed the traffic management measures defined by the different services of the TransAID project, and the required message flow for each service has been defined. Each message flow describes how, when, and where the vehicles communicate between them, and between them and the infrastructure, to execute the traffic management measures. Then, this document provides ananalysis of the MCM generation rules. As highlighted for the CPMs, MCM messages should be transmitted with a frequency high enough to guarantee that the vehicles' manoeuvre coordination is possible. However, a too frequent exchange of MCM messages can increase the channel load to the point that it can negatively impact the performance and scalability of the V2X network. The conducted analysis has shown the importance of considering the vehicular context for the generation of the MCM messages in order to achieve a good balance between channel load and reliability for a safe execution of the cooperative manoeuvres. In particular, two main MCM generation rules approaches have been developed: a) the riskapproach that measures the risk of vehicles with their neighbours and adaptsthe transmission rate based on the risk;b) the tracking trajectories approach that measures the variations between the trajectories transmitted by a vehicle and only sends a new message when the variation is significant. The analysis performed showed that the benefits of both approaches as the risk approach increases the possibilities of successful coordination while the tracking trajectories approach performs an efficient use of the communications channel while keeping neighbours updated about any change in the trajectory.

This present document is Deliverable D3.2 entitled "Cooperative manoeuvring in the presence of hierarchical traffic management", which was prepared in the context of the WP3 framework of the TransAID project. The scope of this document encompasses the modelling and simulation of cooperative manoeuvring in the context of the microscopic traffic simulation activities conducted within TransAID. Initially, the state of the art in the domain of cooperative manoeuvring is provided and then two different cooperative manoeuvring frameworks are introduced. The first one is a decentralized framework where cooperative manoeuvring is solely based on vehicle-to-vehicle (V2V) communications, while the second one is a centralized framework that utilizes vehicle-toanything (V2X) communications. A work zone scenario is used to elaborate on the operation of the centralized approach. The logic for simulating the decentralized approach in the microscopic traffic simulator SUMO is subsequently introduced along with the corresponding functionalities that were developed within SUMO for this purpose. Cooperative manoeuvring is coupled with hierarchical traffic management by explaining how the decentralized approach can be integrated in the traffic management plans that were developed for each use case examined in the context of TransAID. Cooperative manoeuvring is coupled with traffic separation in SUMO and a timeline of cooperative manoeuvring actions in the simulation is presented. Coupling with communications is also addressed. Moreover, adaptations to the driver-vehicle models encompassing communication requirements are proposed to enable integration in iTETRIS. Finally, recommendations for finetuning of driver-vehicle models in simulation are provided based on the findings of the real-world prototype experiments.

This Deliverable 6.2 of the TransAID project presents and evaluates the simulation results obtained for the scenarios considered during the project's first iteration. To this end, driver- and AV-models designed in WP3, traffic management procedures developed in WP4, and V2X communication protocols and models from WP5 were implemented within the iTETRIS simulation framework. Previous main results from Deliverable 4.2, where baseline and traffic management measures without V2X communication were compared, have been confirmed. While not all scenarios' traffic KPIs were affected, the realistic simulation of V2X communication has shown a discernible impact on some of the TransAID traffic scenarios, which makes it an indispensable modelling aspect for a realistic performance evaluation of V2X traffic scenarios. Flaws of the proposed traffic management algorithms concerning wireless V2X communication and the accompanying possibility of packet loss have been identified and will be addressed during the project's second iteration. Finally, lessons learned while working on these simulation results and assessments have additionally been described in the form of recommendations for the real-world prototype to be developed in WP7.

The objective of the TransAID (Transition Areas for Infrastructure-Assisted Driving) project is to deal with situations that cooperative and automated vehicles (CAV) might face when they are approaching to traffic conditions or zones that their automated systems are not able to handle by themselves. In those cases, the driver will be required to take control of the vehicle; this is the socalled Transition of Control (ToC). TransAID develops and demonstrates traffic management procedures and protocols to increase the overall traffic safety and efficiency specially at transition areas (i.e. zones where ToCs should take place) considering the coexistence of CAVs, autonomous vehicles (AVs), cooperative vehicles (CVs) and legacy vehicles (LV). TransAID measures require the use of communications between vehicles (V2V), and between vehicles and the road infrastructure (V2I) which are mainly used to gather information about the traffic stream through cooperative sensing and to support in the coordination of the vehicles maneuvers through cooperative maneuvers. In this context, this document shows the sensor devices and techniques to fuse their data that are being developed in TransAID. This includes techniques implemented at camera-equipped infrastructures that are able to detect, create bounding boxes and uniquely track objects using optical flow, and at the vehicle employing a hybrid sensor fusion strategy which contains a low-level LIDAR fusion module, that transforms the sensor data of multiple laser scanners into a common coordinate system, and an object-level fusion module, that fuses in-vehicle sensor data with data coming from neighbouring vehicles. The document also shows the cooperative techniques that are being designed to enable the Collective Perception Service (CPS) in line with ETSI. The ETSI's CPS entails the continuous exchange of Collective Perception Messages (CPM) that include a logic representation of the objects detected by the sensors and which are useful to improve the vehicles' and the infrastructure's perception of the driving environment. A key aspect for the efficient execution of the CPS is the definition of appropriate generation rules for the transmission of the CPMs, i.e. how often they are transmitted and what information do they include. This document includes a comprehensive analysis of the effect on the communications performance and information awareness of different CPM generation rules that are being considered in ETSI. In particular, the CPM generation rules follow a periodic policy (at 10Hz or 2Hz) where all detected objects are included, or a dynamic one where only the objects fulfilling some requirements are included. The conducted analysis has shown that there is a trade-off between perception capabilities and communications performance/scalability: vehicles detecting the same object(s) and including them in their CPMs create redundant detection which can help improve the perception capabilities but generate higher channel load levels and therefore impact the performance of V2X networks. The obtained results show that the ETSI's dynamic generation policy significantly reduces the communications channel load compared with the periodic ones, without compromising the perception capabilities. In the framework of TransAID, advanced policies will be proposed to further optimize the CPM, both its content and transmission triggering conditions, in order to achieve the necessary levels of redundancy and minimize the impact of the implementation of CPM in the stability and scalability of future V2X networks. In addition, this document investigates existing cooperative driving mechanisms, and specially the ETSI approach on manoeuvre coordination. The ETSI's Manoeuvre Coordination Service (MCS) is defining new concepts and messages which can be used to coordinate manoeuvres between vehicles. TransAID is actively participating in this process, e.g., by means of the definition of the Manoeuvre Coordination Message (MCM) and extending the role of the infrastructure to support the vehicles' manoeuvres coordination under certain scenarios and conditions. In this context, this document presents the message flow for the set of services that are being considered in TransAID. First, this document has analysed the traffic management measures defined by the different services of the TransAID project, and the required message flow for each service has been defined. Each message flow describes how, when, and where the vehicles communicate between them, and between them and the infrastructure, to execute the traffic management measures. Then, this document provides a preliminary analysis of the MCM generation rules. As highlighted for the CPMs, MCM messages should be transmitted with a frequency high enough to guarantee that the vehicles' manoeuvre coordination is possible. However, a too frequent exchange of MCM messages can increase the channel load to the point that it can negatively impact the performance and scalability of the V2X network. The conducted analysis has shown the importance of considering the vehicular context for the generation of the MCM messages in order to achieve a good balance between channel load and reliability for a safe execution of the cooperative manoeuvres.

This deliverable is a direct successor of Deliverable 7.1 [1], which has introduced all vehicles, test tracks and used hardware, and also proposed system architectures of the different used components. D7.1 has also introduced several system requirements for each component and for each scenario, which has to be implemented. D7.2 now shows the results of the first project integration phase. The system implementation is described for the different components of the infrastructure part as well as for the vehicle part. It is shown how both parts communicate in the real world during the first project iteration by presenting the used ASN.1 message definitions (in the Annex) and details about the communication software. Furthermore, a feasibility assessment has been performed by the project partner HMETC. For this, each scenario has been divided into test cases, which have been implemented in the real world prototypes, and demonstrated on a test track in northern Germany. Each test case is linked to related requirements set up in D7.1. During the feasibility assessment, the compliance with all requirements has been checked. In addition, the overall "look and feel" of the prototype and the performance in each test case has been rated and described. In summary, most of the requirements were met. Nevertheless, some deviations have been found. Most of those deviations will be fixed during the second iteration of the project, but there were also some minor points, which need to be reformulated during the second iteration. These points include some identified weaknesses and some needed re-interpretations of existing fields in the used messages. Altogether, it could be shown that the TransAID ideas can be put into real-world to help future automated vehicles to better cope with possible threats and to gain higher performance on the road.

Los sistemas de comunicaciones móviles han experimentado una notable evolución en las últimas décadas con la aparición de nuevas tecnologías de acceso radio diseñadas para incrementar la capacidad del sistema y soportar mayores tasas de transmisión. Esta evolución se ha centrado principalmente en el marco del concepto tradicional de arquitectura celular centrada en infraestructura en la que cada estación móvil comunica directamente con la estación base. Las comunicaciones celulares tradicionales experimentan dificultades para proveer niveles de calidad de servicio (Quality of Service, QoS) elevados y homogéneos en toda la celda (en particular en los límites de la celda) debido a la atenuación que sufre la señal con la distancia y la presencia de obstáculos. En este contexto, un cambio en el paradigma es perseguido en el diseño de los futuros sistemas de comunicaciones móviles (los sistemas 5G) que deberán soportar de una manera eficiente los diversos requisitos de QoS y calidad de experiencia (Quality of Experience, QoE) del tráfico de datos de las redes móviles que crece a tasas exponenciales. Esta tesis defiende la necesidad de explorar y evolucionar desde las actuales arquitecturas celulares centradas en la infraestructura a tecnologías inalámbricas centradas en los dispositivos que sacan provecho de la inteligencia, y los recursos de comunicación y computación de los dispositivos móviles inteligentes. Una forma de conseguir estos objetivos es explotando las comunicaciones dispositivo a dispositivo (Device‐to‐Device, D2D) y las redes celulares multi‐salto (Multi‐hop Cellular Networks, MCNs). En las redes MCNs, los dispositivos móviles pasan a ser productores/consumidores de conectividad inalámbrica actuando como pasarela entre la infraestructura celular y otros dispositivos. Estudios anteriores han demostrado el potencial de las redes MCNs para conseguir importantes beneficios de capacidad y eficiencia energética, a la vez que proveen de mayores y más homogéneos niveles de QoS y QoE. Sin embargo, hasta el momento, las investigaciones realizadas se han limitado generalmente a estudios analíticos y de simulación, y existe por lo tanto la necesidad de demostrar los beneficios de las redes MCNs de manera experimental. En este contexto, una primera y significativa contribución de esta tesis es la evaluación experimental del rendimiento de las redes MCNs a través de pruebas de campo en redes celulares comerciales. Las pruebas de campo llevadas a cabo persiguen validar y cuantificar los beneficios que las redes MCNs utilizando retransmisores móviles pueden proporcionar sobre los sistemas celulares tradicionales. Para ello, esta tesis ha diseñado e implementado una plataforma hardware con las herramientas software necesarias para monitorizar la operación y la QoS de los procesos de retransmisión en los enlaces multi‐salto, y que permite investigar los beneficios de las redes MCNs y las condiciones en los que estos beneficios pueden obtenerse. Utilizando los datos obtenidos de las medidas de campo, esta tesis extrae un conjunto único de modelos empíricos que caracterizan el rendimiento de las comunicaciones MCN, y que pueden ayudar al diseño, testeo y optimización de protocolos de comunicación y de red para redes MCNs en estudios analíticos y de simulación. De manera complementaria a estos estudios, esta tesis propone mejorar la eficiencia en la transmisión del tráfico de datos tolerante a retardos por medio de la integración de técnicas de red oportunistas en las redes MCNs. Los mecanismos oportunistas explotan la tolerancia al retardo que caracteriza a alguno de los servicios de datos más relevantes para buscar las condiciones de transmisión más eficientes en las redes MCNs. En este contexto, esta tesis desarrolla primero un entorno analítico para redes MCNs oportunistas diseñado para identificar la configuración óptima en términos de eficiencia energética. Utilizando esta configuración óptima como referencia, esta tesis propone entonces un conjunto de mecanismos oportunistas que explotan información de contexto proporcionada por la red celular y que demuestran su potencial para contribuir de manera notable a alcanzar los requisitos de capacidad y eficiencia energética perseguidos en las redes 5G.

Future wireless networks are expected to provide high bandwidth multimedia services in extended areas with homogeneous Quality of Service (QoS) levels. Conventional cellular architectures might not be able to satisfy these requirements due to the effect of surrounding obstacles and the signal attenuation with distance, in particular under Non Line of Sight (NLOS) propagation conditions. Recent studies have investigated the potential of Multi-hop Cellular Networks (MCNs) to overcome the traditional cellular architecture limitations through the integration of cellular and ad-hoc networking technologies. However, these studies are generally analytical or simulation-based. On the other hand, this paper reports the first experimental field tests that validate and quantify the benefits that MCNs using mobile relays can provide over traditional cellular systems., 15 pages, 7 figures