High-Speed Serial Links for Safer, Smarter Cars

High-Speed Serial Links for Safer, Smarter Cars

Have you noticed how congested our roadways are getting, especially in metropolitan areas? You might be able to do a conference call on your drive into the office, but this time in transit is generally not particularly productive. All this changes dramatically when self-driving cars hit the road. Imagine the efficiencies of being able to check emails and work on reports, research, and other projects while your car navigates its way through traffic.

Testing of autonomous vehicles is already underway in various cities around the world. In fact, General Motors and Cruise Automation (which GM purchased last year) announced last month that they've developed a self-driving car that is designed for mass production. While GM and Cruise are claiming that this is the first such car ready for full-scale production, Tesla has already begun equipping all of its electric vehicles with a sensor suite that enables self-driving. Chrysler is building several hundred autonomous Pacifica minivans for Waymo (Alphabet’s self-driving division).

Meantime, the current generation of cars already boasts advanced driver assistance systems (ADAS) with capabilities such as parking assistance, autonomous braking, pedestrian detection, and collision avoidance. Underlying technology such as sensors, cameras, and high-speed serial links are integral to making these capabilities possible—and they'll continue to be crucial as the industry moves toward Level 5 fully autonomous vehicles.    

Real-Time Decision-Making Needs Massive Bandwidth

To make real-time decisions that dictate how a vehicle responds and reacts, ADAS applications must be able to quickly take and process input from multiple cameras and sensors. Camera systems inside vehicles typically boast very high data rates. Consider a surround-view system: each camera here usually has a video stream with 1280 x 800 pixel resolution and a frame refresh rate of 30 f/s. Also relying on cameras are infotainment systems, which are increasingly serving up high-resolution content and processing for both audio and video data. In many of today's cars, it's common to find up to eight cameras supporting safety functions. The mix of safety and infotainment will drive future vehicles to have more than a dozen cameras, several high-definition displays, and serial links to transport all of this data. And don't forget vehicle-to-vehicle (V2V) and vehicle-to-everything (V2X) communications! Like ADAS and infotainment systems, V2V, V2X, and sensor fusion systems all require high bandwidth and data integrity to enable vehicles to share and act on data from each other and roadway infrastructure.

According to Strategy Analytics, bandwidth requirements are projected to grow by a factor of roughly 25 from this year to 2020. Higher frame rates and resolutions will only place additional pressure on automotive bandwidth. Yet, this is what's needed to support the burgeoning volumes of data that online, in-vehicle activities like streamed videos, video conferencing, gaming, and social media will demand. When it comes to the underlying data transport technology, there are growing challenges to address around bandwidth, data integrity, interconnect complexity, as well as the harsh nature of the operating environment. Serial link technology must perform well inside this automotive environment to support the blazing-fast speeds, high reliability, and low latency required.

An Ethernet backbone is fairly common in many of today's cars. It can transport data over a link 100x faster than a CAN bus. However, using Ethernet also requires compression of video feeds, and it simply isn't fast enough for the requirements of today's or tomorrow's vehicles. Carmakers increasingly need to be able to transport megapixel resolution images in the vehicle, while also meeting stringent requirements around space and power budget in the cameras. 

Next-Gen High-Speed Serial Links for 4K Video

Maxim's next-generation gigabit multimedia serial link (GMSL) serializer and deserializer (SerDes) technology fully supports the high bandwidth, complex interconnect, and data integrity requirements required for future ADAS and infotainment systems. 

GMSL SerDes technology simultaneously transports HD video, audio, control information, aggregated sensor data, and Gigabit Ethernet over 15m of a single coaxial cable or 10m to 15m of shielded-twisted pair cabling. Since the technology can transport multi-megapixel images without compression, GMSL can support the machine vision technology that’s quickly becoming integral for safety features like object and pedestrian detection. The SerDes technology also features a built-in spread-spectrum capability that reduces electromagnetic interference (EMI) of the link. Requiring only shielded twisted pair or coax cables, GMSL technology simplifies the design while reducing weight, cost, size, and power consumption.

GMSL: Paving the Way for Smarter, Safer Cars

Today's vehicles are already incorporating more safety and entertainment features that are driving up interface bandwidth demands. Tomorrow's cars will become remote workstations during the daily commute or entertainment centers on a long road trip, further increasing the need for fast transport and processing of multiple data types. GMSL SerDes technology paves the way for 4K video, sensor data aggregation, Gigabit Ethernet, and audio, helping you design smarter, safer cars for the future.