Based on cellular network technology, the C-V2X is a highly advanced wireless connectivity technology that is compatible with current trends in safe driving and automated driving solutions with the scalability to upgrade 5G in the future. The C-V2X can use direct communication mode to support direct communication with other cars, pedestrian terminals and roadside infrastructure (such as traffic signals and construction areas) without using a cellular network or becoming a mobile data telecommunication user.
In terms of advanced vehicle-to-everything technology, Qualcomm is very important in both the C-V2X (Cellular Vehicle-to-Everything or Cellular-V2X) and 802.11p-based DSRC services (we will have two chips Commercialization). Qualcomm has just launched a commercial 802.11p/DSRC solution and announced the launch of the first C-V2X direct-communication chipset at the end of this year (2018).
Qualcomm was one of the first companies to support 802.11p and has participated in global demonstration and pilot projects over the past decade. In terms of C-V2X, Qualcomm currently cooperates with Audi, PSA, Ford, Nissan and other ecosystem participants to conduct testing programs in Europe, North America, China, Japan and South Korea.
V2X's two radio technologies
There are two key specifications for V2X direct communication, both of which are designed to operate on the 5.9 GHz ITS spectrum and are able to operate independently of the cellular network, coverage or network operator's participation. The following is a brief summary of each. Explanation:
Based on 802.11p-based technology: IEEE 802.11 was standardized in 802.11a Wi-Fi technology in 1999 to support US and European 802.11p radios, commonly referred to as DSRC and ITS-G5 respectively. The 802.11p specification was completed in 2012. Using the half-clocked version of 802.11a, utilizing radio technology that is now more than two decades old, this radio technology is used to replace wireless Ethernet (Ethernet) cables rather than high-speed mobile applications. 802.11p, due to its vulnerability to congestion and low performance, has limited scope and undefined performance areas, limiting the availability of services and the overall application set, and of course doubting its support for security capabilities. While 802.11p is innovative, cars now have a lot of active sensors, including cameras, radar, and lidar (LiDar), all of which force V2X wireless sensors to provide extra value, including greater distance and reliability, especially in Other vehicles and buildings interfere with the vehicle vision system in the NLOS program.
C-V2X: The 3GPP standards organization has recently optimized the LTE Direct technology and defined in 2017 3GPP Release 14 that automotive applications are optimized, commonly referred to as Cellular-V2X direct communication, or PC5 or Sidelink. The advantages of the C-V2X are based on high-speed mobile application technologies and further improvements in automotive use cases. Based on 802.11p research over many years, the basic development of wireless communication and the need to support security and automatic driving enhancements have been observed. Car application. The C-V2X includes direct communication and web-based communication, but in this article, we are totally focused on supporting car-to-vehicle (V2V), car-to-vehicle (V2I), and car-to-person (V2P), although car-to-network (V2N) The value and importance of ) is very important. This is because from the initial basic telematics services, connected message entertainment, to the automotive applications that are now designed to support the remote operation of driverless vehicles.
In the past 20 years, the direct communication between 802.11p and Cellular-V2X has been separated, and wireless communication has evolved, from the evolution of 2G cellular networks to the emergence of 5G, and the fundamental changes in mobile devices. Even in the Wi-Fi space, after 802.11a, there are several generations of improvements in 802.11b, 802.11g, 802.11n, 802.11ac, and now 802.11ax. 802.11p is a pioneering technology that will help future 5G protocols and applications.
10 Things to Know C-V2X
1. Prepare time for commercialization: It is expected that the C-V2X will be ready to use the products of the Qualcomm 9150 C-V2X chip set for production in the early 2019s to enter the competitive ecosystem. 3GPP Release 14 PC5 is ready to support automotive manufacturers, Tier 1 suppliers, Tier 2 module manufacturers, automotive software developers, mobile operators, global semiconductor companies, test equipment suppliers, telecommunications providers, transportation Signal providers and road operators. From more than 80 global members of the 5G Automotive Association (5GAA), including car manufacturers from major regions, to promote automotive investment through C-V2X using standardized and developed ITS software and applications over the years, despite the use of radio switching Technology, but it can still be fully utilized. Ecosystems (automotive suppliers and software suppliers) are ready for commercialization in vehicles and restricted areas. The C-V2X shortens the development time of straight-forward radio swap-outs that are common in wireless technology, changes the PHY/MAC, and retains software and applications. Incorporating the C-V2X into an in-vehicle embedded wireless modem can save costs, which can accelerate the market surcharge rate of C-V2X direct communication.
2. Excellent range and radio performance: The C-V2X can provide higher communication range (about twice the line-of-sight) by improving the overall technological advancements of modulation and coding and better receiver and LTE technology. Good Non-Line-of-Sight performance, improved reliability (lower packet data error rate), higher capacity in a more intensive environment than IEEE 802.11p based radio technology Has excellent congestion control capabilities. This is just based on basic physics. The well-known problem of 802.11p hiding nodes in the CSMA protocol may lead to excessive packet collisions, but C-V2X is designed to ensure that close two devices do not pick resources in the same frame, thereby increasing performance in dense environments . This is confirmed by empirical analysis, simulations, laboratory results and field test results.
Enhancements in C-V2X direct communication can bring superior performance for security and future automatic driving in different situations such as different road/traffic conditions and vehicle speed. After rigorous testing, car manufacturers demonstrated the superior performance of the C-V2X PC5 and IEEE 802.11p.
3. Predictable performance: Different from 802.11p, C-V2X direct communication aims to provide predictable and consistent performance in real-life scenarios based on standardized minimum performance requirements specified in the 3GPP radio specifications. For example, 3GPP defines the minimum requirements for Block Error Rate (BLER) for different channel conditions and reliable communication with speeds up to 500 km/h (eg, in the presence of high Doppler, fading, time, and frequency errors). Unlike IEEE 802.11p-based technologies, C-V2X direct-communication transceiver/chipset vendors must comply with these specifications in order to achieve predictable and uniform performance. Since 802.11p does not specify minimum performance requirements, its performance may not be predictable and does not apply to secure applications in real-world automotive deployment scenarios. 802.11p is susceptible to interference because the lack of symbolic interleaving makes the transmission susceptible to short pulses.
4. Compatibility: The C-V2X is intended to provide an evolution path for 5G and is backwards/forward compatible. Through the design, the C-V2X evolution can take advantage of the latest advances in wireless communications while maintaining backward compatibility. The Rel-14 C-V2X has undergone a strong evolution toward 5G NR-based C-V2X, enabling the addition of new features while enhancing Rel-14 while maintaining backward compatibility. Rel-14 can be used for basic safety communication between vehicles. The 5G NR-based C-V2X can be used for advanced automatic driving car use cases. The 5G NR-based C-V2X is designed to provide high productivity, support for broadband, ultra-low latency and reliability for autonomous vehicle use cases such as sensor sharing, intent sharing, and 3D HD map updates. Because C-V2X direct communication does not rely on a cellular network, R14 and future versions can operate without relying on or relying on wireless network coverage. The C-V2X technology platform from Rel-14 to 5G NR-based C-V2X is security-aware, robust and reliable, and can provide a rich and differentiated experience.
5, cost-effective: C-V2X can be integrated into the cellular modem chipset products, compared with 802.11p / DSRC, C-V2X-based solutions more cost-effective.
6, ITS spectrum and investment can be reused: C-V2X direct communication designed for ITS spectrum, its radio exchange can shorten its development time, V2X software investment can be reused for many years. It can benefit from the established security and transport layers and application protocols defined by the automotive standards organization, including: SAE, ISO, ETSI, and Institute of Electrical and Electronics Engineers (IEEE) 1609 Working Group).
Low latency: The C-V2X is designed for low latency direct communication. Safety messages, such as road hazard warnings, can be sent using low-latency direct communication in the globally uniform 5.9 GHz ITS spectrum. The minimum transmission delay for C-V2X is up to 4ms and may be lower depending on the implementation.
8. High-speed mobile use: Unlike the Wi-Fi technology that replaces Ethernet cabling, the cellular system is designed for high-speed movement. Due to the lack of enhancements in the physical layer, 802.11p requires advanced receivers to operate at high speeds. On the other hand, C-V2X direct communication utilizes its traditional cellular advantages and is designed for high-speed vehicle use cases. Through analysis, R14 C-V2X direct communication can reach a relative speed of 500 km / h in the 5.9 GHz band. The C-V2X direct communication signal design improves the stability performance that can be achieved at high speed without the need for advanced receivers to perform (even advanced receiver implementations that use coded bits are very likely and can provide higher performance). Also unlike 802.11p, in the presence of high Doppler effects, fading, time and frequency errors, its performance is possible by defining minimum performance requirements.
9. Sound Synchronization: Even without a Global Navigation Satellite System (GNSS), C-V2X has a powerful mechanism that can support cost-effective synchronization from different sources. In fact, both V2X technologies rely on GNSS for location information, which is necessary for the operation of ITS security applications. Acquiring microsecond timing is more reliable than acquiring positioning information from a GNSS because timing is robust to multipath errors. In addition, with a small GNSS coverage, the V2X system may lose positioning accuracy before timing accuracy is lost. In the absence of GNSS, 3GPP has defined detailed protocols for vehicles to use different synchronization sources, including other automotive, eNodeB, and RSU timing.
10. Security: Security-centric communication is very important for any V2X application. The C-V2X benefits from the established security and transport layers and application protocols defined by the aforementioned automotive and wireless standards organizations. Also, cellular communication (V2N) can also benefit.
Conclusion
Dedicated Short Range Communication (DSRC) This is a Wi-Fi based communication method. However, this is a relatively traditional technology. It has a history of 15 years and there are some technical defects, such as the limitation of coverage.
If two cars are moving in the opposite direction, the DSRC will only start running when it reaches half the distance and speed of the C-V2X. For example, if two cars are traveling at a speed of 45 kilometers per hour, the C-V2X can warn when the distance is 450 meters. With DSRC technology, targets can only be detected at about 250 meters.
The C-V2X technology helps to detect accident vehicles in a non-linear range. There is an accident vehicle at the turn of the current road. In the normal driving process, the driver’s eyes cannot see the accident vehicle, but when the vehicle enters the range of the C-V2X, the vehicle will receive a notification and know the front In which lane the vehicle is blocked, the location of the vehicle can be broadcast. Drivers can therefore know that there is a danger ahead and reduce the speed to avoid danger.
C-V2X is the standard of 3GPP in R14, and C-V2X is also a continuously evolving and constantly improving standard. Not only that, the investment in C-V2X in the 4G era can also be extended to the 5G era and applied to the 5G infrastructure. This is one of the advantages of C-V2X over DSRC.
Medical Products Making Machine
We are manufacturer of disposable medical products making machine. Our main items are Medical Gowns Making Machine, disposable Doctor Cap Making Machine , nonwoven Examination Pants Making Machine, disposable dust Shoe Cover Making Machine. They are automatically from nonwoven fabric feeding to produce finished goods. The surgical gowns, cap, diaposable pants and shoe cover are ont only used in hospital, they also can use in dust-free environment etc.
Medical Products Making Machine
Medical Products Making Machine,Hospital Sheet Making Machine,Dust Face Mask Machine,Beach Pants Making Machine
KYD Automatic Mask Machine Factory , https://www.kydultrasonic.com