Car networking: mass production starts in China

Car networking technology gets going after years of standstill. Having moved to China's Ministry of Industry and Information Technology already opted for mobile-based networking in 2018 (Cellular Vehicle-to-Everything, C-V2X), Autotalks is the first chipset manufacturer to start mass production.

Autotalks reports that its chipset has been selected for mass production in China. The company delivers an unspecified quantity of its C-V2X chipset to a "leading automotive supplier" who installs it in its Telematics Control Units (TCU). Autotalks previously completed interoperability tests with various partners in 2019, including the chip giant Qualcomm (C-V2X test in Shanghei: 20 companies, 50 vehicles).

Autotalks did not provide details of the chipset properties. After all, it is known from previous tests that Autotalks can use the mobile radio channel called PC5 for its C-V2X implementation.

In general, cars can communicate using the C-V2X technology via two interfaces, Uu and PC5: When using the Uu interface, the C-V2X modem uses the mobile network as an intermediary. Because the network allocates resources, packet collisions are less common with Uu. However, it is completely open who and how much should pay for the use of the mobile network infrastructure. The packet transit times for Uu transmission are also longer than for PC5. With PC5, cars communicate directly with each other. PC5 and Uu can be activated simultaneously. If a cellular network is missing, only PC5 remains.

If modems in C-V2X Sidelink mode (PC5) select radio resources themselves (left), packet collisions always occur. If the cellular network allocates the resources, this only happens when a base station is overloaded.

According to IHS Markit analysts, China is emerging as the leader in car networking this year. According to the study, car manufacturers in China will produce around 629,000 cars with C-V2X by the end of 2020. According to the IHS Markit, the trend should continue until at least 2024.

The WLAN-based V2X technology (IEEE 802.11p, also called DSRC) introduced over ten years ago, on the other hand, is making little progress, although 11p chipsets have been available for around ten years. Autotalks offers Craton2 and secton even combination chipsets with 11p and C-V2X implementations from a single source. There is no mention of 11p in the large Chinese order.

In Japan and the USA, only one 11p car model is available (Toyota Crown and Cadillac CTS). Sales figures in the US are poor; Throughout 2018, the U.S. Department of Transportation only counted 3340 vehicles with an 11p / DSRC module. Meanwhile, the U.S. regulator FCC has lost patience with the 11p technique. Ajit Pai, head of the FCC said in December 2019: "The failure to develop 11p technology is even more noticeable when you consider that 1999 is also the year of the birth of Wi-Fi technology". That is why the FCC wants to remove the radio spectrum from 11p technology and possibly strike completely C-V2X.

Because cars with 11p basically communicate with each other directly (without a base station), the networking technology is only really useful when numerous cars are equipped with it and within range (a few hundred meters). Sudden braking operations can be immediately transmitted to the following vehicles, for example to trigger emergency braking or to warn of black ice or confusing construction sites. The 11p radio is generally not armed against packet collisions.

The EU has not yet made a decision whether to make car networking using 11p or cell phones compulsory. In the summer of 2019, it still looked like 11p would win until large parts of the auto industry and politics had spoken out in favor of the C-V2X. Some experts argue that the EU should simply make networking itself an obligation and allow both technologies. VW announced in autumn 2019 that it would use 11p in the mass production of the Golf model from 2020.

Autotalks plans to showcase its V2X implementation at the Mobile World Congress, which runs in Barcelona from February 24-27. Autotalks will be exhibiting in Hall 5, Stand 5D81.

You can find details on the two methods for car networking, including cost issues, in the following c't articles:


. (TagsToTranslate) 802.11p (t) C-V2X (t) DSRC (t) networks (t) Telematics (t) pWLAN