On the A9 freeway near Allershausen, Germany, Bosch, Vodafone, and Huawei are field-testing the new LTE-V2X technology. The new mobile communication technology enables the direct, instantaneous exchange of information between vehicles. Connected cars can directly transmit information about such things as speed, position, and lane change to all vehicles within a 320-meter radius.
Cars can connect without going through any intermediate channels, which means communication occurs instantaneously. It is hoped that this fast and direct communication between vehicles will optimize the flow of traffic and reduce accident rates. Together with the comprehensive cellular network, it will provide an additional safeguard in the future for fully connected roads.
The companies claim that “real time car-to-car communication makes driving more relaxed, more efficient, and safer. ”
For example, it is Friday afternoon, and the traffic on the A9 freeway near Munich is congested. Other vehicles are constantly cutting in front of the car, forcing the driver to brake abruptly − which is the cause of many accidents, slow-moving traffic, and stress. Intelligent mobile telephony can alleviate some of these problems and help prevent potentially dangerous driving situations from becoming even more critical.
Known as cellular-V2X (vehicle to anything), the technology makes it possible for a car to communicate with other vehicles and its surroundings through mobile telephony. Since February 2017, Bosch, Vodafone, and Huawei have been performing trials of the new, high-performance technology − the first companies in Europe to do so. The A9 freeway in Bavaria is the location for the field tests with the first 5G test modules. For the first time, the companies are demonstrating that driver assistance systems such as ACC adaptive cruise control also benefit from the direct, instantaneous exchange of information between vehicles.
Until now, cellular-V2X has been used as a real-time alert system when changing lanes on the freeway or when the car ahead suddenly brakes. ACC not only warns the driver, but also automatically accelerates and brakes. The new mobile telephony system thus paves the way for automated driving. Achieving the goal of fully connected traffic will involve teaching vehicles to communicate with each other and exchange data directly. Direct communication between vehicles provides information about what is happening in parts of an intersection not visible to the driver, over the crest of a hill, or on the freeway beside or behind the driver’s own car.
Bosch’s flexible V2X platform can accommodate either cellular-V2X or dedicated short range communication (DSRC) to provide partners with a global solution while also supporting region-specific communication requirements.
On the proving ground of the A9 freeway, Vodafone is installing a powerful cellular network for data transmission. As a systems technology partner, Huawei is building the mobile telephony modules for the cars and installing the necessary communications technology at the base stations. Bosch’s role is to integrate the mobile telephony modules and corresponding software into the vehicles and take measurements on site. During the pilot phase, the partners aim to demonstrate under live conditions that direct mobile communication between cars works with extremely low latency, and to show how it differs from Wi-Fi-based alternatives. The comprehensive cellular network also helps provide maximum reliability and facilitates the coordination of car-to-car communication. International bodies are currently working on the specifications for LTE-V2X. For the first time ever in Europe, the Bosch, Vodafone, and Huawei tests build on the latest specifications.
The technology is initially being tested as a real-time warning system for lane changes on the freeway. It is designed so that cars exchange all relevant information, such as speed and position, with other vehicles in the vicinity. During a lane-change maneuver, for example, the driver will receive a warning if a car is approaching at high speed from behind, which could result in an accident. In a situation such as this, it is crucial that information is exchanged instantaneously. The technology will undergo subsequent testing for further scenarios in order to assess what other functions apart from the early warning for lane changes stand to benefit most from swift data transmission. The functions under consideration include alerting drivers to sudden braking maneuvers by a preceding vehicle.
ACC adaptive cruise control maintains the speed specified by the driver and − thanks to a radar sensor − the preset distance to the vehicle in front as well. ACC detects a vehicle that suddenly cuts in front as soon as it enters the radar sensor’s detection range. When cars communicate directly and in real time using cellular-V2X, it is possible to detect such events sooner. Through mobile telephony, connected cars can directly transmit information, such as their position and speed, to all vehicles within a radius of more than 300 meters.
Moreover, they can do so without going through any intermediate channels via the base stations and with virtually no delay. As a result, a vehicle knows the driving behavior of others around it. If, for example, a car suddenly cuts in front of another vehicle, ACC knows what is about to happen − even before it registers with the driver or the radar sensor. The car then automatically adjusts its speed earlier than it would have before, so that the vehicle cutting in can do so smoothly. Once enough distance to the car in front has been re-established, ACC automatically accelerates to the preset speed. Even in congested traffic, this function makes driving even more relaxed and stress-free for drivers, while also preventing abrupt braking and acceleration on the freeway. Overall, traffic becomes smoother and more efficient. Thanks to the foresight provided by the technology, vehicles can go with the flow.