Jiayi Fang

Bio: Jiayi Fang is an academic researcher from Beijing University of Posts and Telecommunications. The author has contributed to research in topics: 3rd Generation Partnership Project 2 & LTE Advanced. The author has an hindex of 5, co-authored 8 publications receiving 667 citations.

Vehicle-to-Everything (v2x) Services Supported by LTE-Based Systems and 5G

Abstract: Vehicle-to-everything (V2X), including vehicle- to-vehicle (V2V), vehicle-to-pedestrian (V2P), vehicle-to-infrastructure (V2I), and vehicle-to-network (V2N) communications, improves road safety, traffic efficiency, and the availability of infotainment services. Standardization of Long Term Evolution (LTE)-based V2X has been actively conducted by the Third Generation Partnership Project (3GPP) to provide solutions for V2X communications, and has benefited from the global deployment and fast commercialization of LTE systems. LTE-based V2X was widely used as LTE-V in the Chinese vehicular communications industry, and LTE-based V2X was redefined as LTE V2X in 3GPP standardization progress. In this article, the overview of requirements and use cases in V2X services in 3GPP is presented. The up-to-date standardization of LTE V2X in 3GPP is surveyed. The challenges and detailed design aspects in LTE V2X are also discussed. Meanwhile, the enhanced V2X (eV2X) services and possible 5G solutions are analyzed. Finally, the implementations of LTE V2X are presented with the latest progress in industrial alliances, research, development of prototypes, and field tests.

Support for vehicle-to-everything services based on LTE

Abstract: Vehicular applications and communications technologies are often referred to as vehicle-to-everything (V2X), which is classified into four different types: vehicle-to-vehicle (V2V), vehicle- to-infrastructure (V2I), vehicle-to-network (V2N), and vehicle-to-pedestrian (V2P) [1]. V2X related research projects, field tests, and regulatory work have been promoted in different countries and regions. In May 2015, the Ministry of Industry and Information Technology (MIIT) of China explained national strategies, "Made in China 2025," about intelligent connected vehicles. In 2020 and 2025, the overall technology and key technologies for intelligent driver assistance and automatic driving will be available in China, respectively [2]. V2X solutions are the critical technologies to support the realization of such visions. Although IEEE 802.11p has been selected as the technology for V2X communications in some countries such as the United States and in Europe, the intrinsic characteristics of IEEE 802.11p have confined the technology to support low latency with high reliability [3, 4]. Standardization of Long Term Evolution (LTE)-based V2X is being actively conducted by the Third Generation Partnership Project (3GPP) to provide the solution for V2X communications that benefit from the global deployment and fast commercialization of LTE systems. Because of the wide deployment of LTE networks, V2I and V2N services can be provided with high data rate, comprehensive quality of service (QoS) support, ubiquitous coverage, and high penetration rate [5]. Meanwhile, LTE can be extended to support V2V direct communications based on device-to-device (D2D) sidelink design to satisfy the QoS requirements, such as low latency, high reliability, and high speed in the case of high vehicle density [6].

Link level performance comparison between LTE V2X and DSRC

Abstract: Applications of VANETs (Vehicular Ad hoc Networks) have their own requirements and challenges in wireless communication technology. Although regarded as the first standard for VANETs, IEEE 802.11p is still in the field-trial stage. Recently, LTE V2X (Long-Term Evolution Vehicular to X) appeared as a systematic V2X solution based on TD-LTE (Time Division Long-Term Evolution) 4G. It is regarded as the most powerful competitor to 802.11p. We conduct link level simulations of LTE V2X and DSRC (Dedicated Short-Range Communication) for several different types of scenarios. Simulation results show that LTE V2X can achieve the same BLER (Block Error Ratio) with a lower SNR (Signal Noise Ratio) than DSRC. A more reliable link can be guaranteed by LTE V2X, which can achieve the same BLER with lower receiving power than DSRC. The coverage area of LTE V2X is larger than that of DSRC.

Method, base station and user terminal for sending random access response

Abstract: The invention provides a method, a base station (eNB) and a user terminal (UE) for sending a random access response, wherein the method comprises the following step that: after receiving a non-competition random access request of the UE on an uplink member carrier, according to a preset carrier strategy, the eNB sends the random access response to the UE on one downlink member carrier supported by the UE. Compared with the traditional method in which the eNB sends the random access response to all downlink member carriers supported by the UE, the invention saves more downlink resources. Correspondingly, the UE in the invention only needs to monitor the random access response on one supported downlink member carrier according to the preset carrier strategy without monitoring all downlink member carriers, thereby more saving electric power consumption of the UE.

The Performance Comparison of LTE-V2X and IEEE 802.11p

Abstract: Vehicle-to-everything (V2X) can improve the road safety, the traffic efficiency, and the availability of infotainment services. Standardization of Long Term Evolution (LTE)-V2X has been actively conducted by the Third Generation Partnership Project (3GPP) to provide the solutions for V2X. In this paper, the challenges and detailed design issues in LTE V2X are discussed. The performance comparison of LTE-V2X and IEEE 802.11p is presented in typical urban and freeway scenarios.

Edge Computing for Autonomous Driving: Opportunities and Challenges

Abstract: Safety is the most important requirement for autonomous vehicles; hence, the ultimate challenge of designing an edge computing ecosystem for autonomous vehicles is to deliver enough computing power, redundancy, and security so as to guarantee the safety of autonomous vehicles. Specifically, autonomous driving systems are extremely complex; they tightly integrate many technologies, including sensing, localization, perception, decision making, as well as the smooth interactions with cloud platforms for high-definition (HD) map generation and data storage. These complexities impose numerous challenges for the design of autonomous driving edge computing systems. First, edge computing systems for autonomous driving need to process an enormous amount of data in real time, and often the incoming data from different sensors are highly heterogeneous. Since autonomous driving edge computing systems are mobile, they often have very strict energy consumption restrictions. Thus, it is imperative to deliver sufficient computing power with reasonable energy consumption, to guarantee the safety of autonomous vehicles, even at high speed. Second, in addition to the edge system design, vehicle-to-everything (V2X) provides redundancy for autonomous driving workloads and alleviates stringent performance and energy constraints on the edge side. With V2X, more research is required to define how vehicles cooperate with each other and the infrastructure. Last, safety cannot be guaranteed when security is compromised. Thus, protecting autonomous driving edge computing systems against attacks at different layers of the sensing and computing stack is of paramount concern. In this paper, we review state-of-the-art approaches in these areas as well as explore potential solutions to address these challenges.

A Tutorial on 5G NR V2X Communications

Abstract: The Third Generation Partnership Project (3GPP) has recently published its Release 16 that includes the first Vehicle-to-Everything (V2X) standard based on the 5G New Radio (NR) air interface 5G NR V2X introduces advanced functionalities on top of the 5G NR air interface to support connected and automated driving use cases with stringent requirements This article presents an in-depth tutorial of the 3GPP Release 16 5G NR V2X standard for V2X communications, with a particular focus on the sidelink, since it is the most significant part of 5G NR V2X The main part of the paper is an in-depth treatment of the key aspects of 5G NR V2X: the physical layer, the resource allocation, the quality of service management, the enhancements introduced to the Uu interface and the mobility management for V2N (Vehicle to Network) communications, as well as the co-existence mechanisms between 5G NR V2X and LTE V2X We also review the use cases, the system architecture, and describe the evaluation methodology and simulation assumptions for 5G NR V2X Finally, we provide an outlook on possible 5G NR V2X enhancements, including those identified within Release 17

Networking and Communications in Autonomous Driving: A Survey

Abstract: The development of light detection and ranging, Radar, camera, and other advanced sensor technologies inaugurated a new era in autonomous driving. However, due to the intrinsic limitations of these sensors, autonomous vehicles are prone to making erroneous decisions and causing serious disasters. At this point, networking and communication technologies can greatly make up for sensor deficiencies, and are more reliable, feasible and efficient to promote the information interaction, thereby improving autonomous vehicle’s perception and planning capabilities as well as realizing better vehicle control. This paper surveys the networking and communication technologies in autonomous driving from two aspects: intra- and inter-vehicle. The intra-vehicle network as the basis of realizing autonomous driving connects the on-board electronic parts. The inter-vehicle network is the medium for interaction between vehicles and outside information. In addition, we present the new trends of communication technologies in autonomous driving, as well as investigate the current mainstream verification methods and emphasize the challenges and open issues of networking and communications in autonomous driving.

On the Performance of IEEE 802.11p and LTE-V2V for the Cooperative Awareness of Connected Vehicles

Abstract: To improve safety on the roads, next-generation vehicles will be equipped with short-range communication technologies. Many applications enabled by such communication will be based on a continuous broadcast of information about the own status from each vehicle to the neighborhood, often referred as cooperative awareness or beaconing. Although the only standardized technology allowing direct vehicle-to-vehicle (V2V) communication has been IEEE 802.11p until now, the latest release of long-term evolution (LTE) included advanced device-to-device features designed for the vehicular environment (LTE-V2V) making it a suitable alternative to IEEE 802.11p. Advantages and drawbacks are being considered for both technologies, and which one will be implemented is still under debate. The aim of this paper is thus to provide an insight into the performance of both technologies for cooperative awareness and to compare them. The investigation is performed analytically through the implementation of novel models for both IEEE 802.11p and LTE-V2V able to address the same scenario, with consistent settings and focusing on the same output metrics. The proposed models take into account several aspects that are often neglected by related works, such as hidden terminals and capture effect in IEEE 802.11p, the impact of imperfect knowledge of vehicles position on the resource allocation in LTE-V2V, and the various modulation and coding scheme combinations that are available in both technologies. Results show that LTE-V2V allows us to maintain the required quality of service at even double or more the distance than IEEE 802.11p in moderate traffic conditions. However, due to the half-duplex nature of devices and the structure of LTE frames, it shows lower capacity than IEEE 802.11p if short distances and very high vehicle density are targeted.

5G D2D Networks: Techniques, Challenges, and Future Prospects

Abstract: The increasing number of mobile users has given impetus to the demand for high data rate proximity services. The fifth-generation (5G) wireless systems promise to improve the existing technology according to the future demands and provide a road map for reliable and resource-efficient solutions. Device-to-device (D2D) communication has been envisioned as an allied technology of 5G wireless systems for providing services that include live data and video sharing. A D2D communication technique opens new horizons of device-centric communications, i.e., exploiting direct D2D links instead of relying solely on cellular links. Offloading traffic from traditional network-centric entities to D2D network enables low computational complexity at the base station besides increasing the network capacity. However, there are several challenges associated with D2D communication. In this paper, we present a survey of the existing methodologies related to aspects such as interference management, network discovery, proximity services, and network security in D2D networks. We conclude by introducing new dimensions with regard to D2D communication and delineate aspects that require further research.