West Point Precision's Guo Rongzhe: Technological evolution trend of in-vehicle high-speed interconnection

From September 24 to 26, the "2024 China Automotive Supply Chain Conference and the 3rd China Intelligent Connected New Energy Vehicle Ecological Conference" was held in Wuhan. This conference was co-organized by the China Association of Automobile Manufacturers and Dongfeng Motor Group Co., Ltd., with the theme of "New Challenges, New Countermeasures, New Opportunities-Promoting the Sustainable Development of China's Automotive Supply Chain". A total of 6 meetings were set up, including 1 closed-door meeting, 1 conference forum and 4 theme forums. There were also a series of releases or supporting activities such as the release of the supply chain development report, the promotion of innovative achievements, the Hong Kong Auto Show and Forum, and the first stop of the China Automotive Supply Chain Collaborative Innovation National Tour (Dongfeng Automobile Station). Among them, at the "Theme Forum 1: Developing a New Supply Chain-Enabling New Advantages of New Energy Vehicles" held on the afternoon of September 25, Shenzhen West Point Precision Technology Co., Ltd. CTO Guo Rongzhe delivered a wonderful speech. The following content is a transcript of the on-site speech:

Guo Rongzhe, CTO of Shenzhen West Point Precision Technology Co., Ltd.

Dear leaders, distinguished guests, and participants, good afternoon.

I am from Shenzhen West Point Precision Technology Co., Ltd. We mainly develop and produce some high-speed connectors and wiring harnesses for use in the automotive, communications and computing fields. I am very grateful to the organizers of the conference for giving us this opportunity to share with you some of my understanding and thoughts on automotive high-speed interconnection at this important moment.

First, let’s talk about why we need high-speed in-vehicle transmission. There are mainly two aspects.

On the one hand, there is intelligent driving. Nowadays, cars are equipped with more and more high-definition cameras, various radars and sensors, 5G antennas, GPS antennas, etc. The interconnection between these sensors and computers mostly uses high-speed data connections, and the requirements for speed are getting higher and higher.

On the other hand, the intelligence of the cockpit continues to be upgraded and iterated, and even high-definition projection has appeared. The resolution of the display system has also been increased from the original 480 lines to 4K8K. These improvements in comfort and experience have also brought about increases in data transmission capacity, while also putting higher requirements on the signal integrity of data transmission.

This page provides an overview of commonly used automotive high-speed connectors and their applications.

First, there are the earlier interconnection solutions such as USB, HDMI, HSD, etc., which are mainly used in entertainment systems, large electronic screens, HUD and other scenarios. The market trend should be maintained or even replaced by other solutions to varying degrees.

Next are Fakra and minifakra., RF connectors and wiring harnesses, which are widely used in scenarios such as intelligent driving, surround view systems and GPS antennas. Minifakra. appeared later than Fakra. Minifakra. is smaller in size and has a higher speed, so Minifakra has now largely replaced Fakra.

Then there is the in-vehicle Ethernet solution, which has been a popular solution in recent years. The transmission of digital signals has great advantages in terms of transmission efficiency, cost, volume, and weight. Therefore, it can be concluded that this solution will have great prospects in future practical applications. Today we will also focus on analyzing the development trends of this type of solution.

Finally, there is the transmission of light. The application of this solution in vehicles is still in the early pre-research stage. Due to some obvious advantages and disadvantages, its future prospects will have to be tested by time.

Here we analyze the advantages and disadvantages of optical transmission:

First of all, the advantages, optical transmission has very good S| performance. The upper left corner of the picture lists the loss values ​​of different transmission media at a certain frequency. We can see that the loss of optical transmission is very small, which is a few tenths of that of PCB at a frequency of 20GHz. In addition, there is no need to consider crosstalk and interference in optical transmission, and the operating frequency can be very high. This is the biggest advantage of optical transmission. In addition, other advantages of optical transmission include long transmission distance, small size, light weight, abundant raw material sources, and cheap raw materials.

So what are its disadvantages for automotive applications: The first is the high cost and high power consumption of short-distance transmission. We can see that the two pictures on the right are schematic diagrams of optical transmission. The analog signal is converted into a digital signal, and then the photoelectric conversion is converted into a light signal to be sent out. The other end also has photoelectric conversion and digital-to-analog signal conversion. The addition of these chips and sensors will undoubtedly bring us additional costs and increase power consumption. Another point is the reliability issue. The interface end face of the optical connector is made of very smooth and hard glass. Under high-speed vibration conditions, friction corrosion will occur on the two end faces. After a long time, the smoothness of the mating surface will be damaged, affecting the reliability of the transmission. Another thing is that the material of the optical fiber is very brittle and can be easily broken.

The high-speed transmission in our automotive application scenarios is less than five or six meters. At present and even in the next ten years, copper transmission can easily solve the application needs of automotive high-speed transmission. On the whole, I personally think that optical transmission will not be used in vehicles so soon, at least not in large quantities. Copper transmission will still be the mainstream.

Representatives of RF connectors include Fakre and Minifakra. They both transmit analog RF signals and can do the same thing, but Minifakra appeared later. Its size and performance are much better than Fakra. The upper right corner is Minifakra. The lower left corner is Fakra. We can see that the 2-port Eakra is larger than the 4-port Minifakra, so many car manufacturers have abandoned Fakra and replaced it with Minifakra on a large scale.

High integration will also become a trend. You can see from this picture that automotive Ethernet and automotive RF are integrated. Low-speed control signals and even power terminals, etc., will be greatly improved in size and board area after being combined together. At the same time, the cost will also have many advantages. Friends who have cooperated with Tesla believe that they have felt that there are more and more mixed projects recently. Therefore, we are developing some Lego-like building blocks to modularize the corresponding interfaces. You can build any configuration you want. I believe that we will provide our customers with more choices in the future.

I think automotive Ethernet has the most potential. Here is a brief introduction to what automotive Ethernet connectors are. With the development of high-level intelligent driving and automotive intelligence, the amount of data generated and transmitted by the vehicle side has increased. As an economical, efficient, and lightweight transmission solution, automotive Ethernet transmission has been widely used in recent years.

Two typical automotive Ethernet connectors are listed on the right.

The two pictures in the upper right corner are automotive Ethernet connectors with speeds of 1 Gigabit or less. TE, Rosenberger and other companies have similar solutions, and the compatible cables can be unshielded or shielded twisted pair cables.

As the speed increases, the following type of automotive Ethernet connectors were developed, and many companies have also launched similar solutions. This type of automotive Ethernet connector can generally support 10G speeds and has the possibility of being upgraded to 25G or even 56G.

Here we need to understand some concepts of Ethernet rate. Here are two pictures. The left one is the Ethernet rate development roadmap for the data communication industry. We can see that the current single-channel 112G has been basically developed, and the single-channel 224G is already under development.

On the right is a signpost for in-vehicle high-speed interconnection. We are currently using Gigabit, and single-channel 5G and 10G will soon be commercially available. This is not to show how backward automotive Ethernet is, but to show that we can raise higher requirements for the speed of in-vehicle Ethernet, and we can also make greater improvements. In addition, we can also borrow some mature experience in the 1CT field and use it in automobiles.

Here is a high-density automotive Ethernet interconnection solution we propose, which has achieved significant improvements in density, speed, cost and weight.

The one above is the current 4-port, 10G automotive Ethernet connector, and the one below is our proposed 32-port, 112G high-density solution.

We can see that with this high-density solution, the cost of a single differential pair is only 1/3 to 1/2 of the current 10G automotive Ethernet, the overall weight is reduced by 60%, the speed is increased by 10 times, and the overall size is only 1/8 of 10G Ethernet.

In this way, perhaps we only need one connector to connect all the sensors in the car, or we can use it to stack on-board supercomputing modules to obtain greater computing power.