This growth trend is expected to continue beyond 2025 with vehicles supporting up to 20 cameras becoming a reality in the not too distant future.
Along with the number of cameras increasing, the need for higher camera resolutions continues at pace. This resolution increase is driven by two main factors. The first factor is the need to support more ADAS features, as these features require higher resolution to achieve greater and more accurate functionality. The second factor is the need to display higher quality images as consumers now demand excellent visual quality comparable to their smartphone’s high resolution displays.
The problem here is that the lifetime of a smartphone is significantly shorter than that of a car and, therefore, automobile manufacturers need to ensure they implement the latest display technology at the start of production so that their display systems stay relevant for as long as possible.
Original equipment manufacturers (OEMs) continue to increase the size and resolution of the displays they use. As a result, when displaying a camera image on these larger and higher resolution displays, higher resolution cameras are required because using existing standard definition (SD) cameras results in a very poor user experience. A low resolution camera results in poor video quality. Additionally, many unwanted visual artifacts such as dot crawl and color leakage are clearly visible on these displays—therefore, using SD cameras to drive these displays is no longer acceptable. To provide a better customer experience, high definition (HD) cameras are required.
The addition of these cameras comes at a cost. This cost is not just limited to increased sensor and image processing costs, but also the transfer of the video data from the camera to the processing units over copper wiring incorporated in the vehicle harness. Additional copper wiring for the car camera link may not seem like a big issue, but with the vehicle harness being the third most expensive component in a car (behind engine and chassis), wiring and connector selection is of critical importance to car OEMs. Harnesses are built one at a time and consume up to 50% of the cost of labor for the entire car. The wiring harness is also the third heaviest component1 in the car (behind the chassis and engine). Inserting these wire harnesses into the vehicle proves increasingly problematic on vehicle production lines, with any additional manufacturing steps driving costs even further. Adding any additional weight to the vehicle must be avoided as we move toward greater electric vehicle use, where any additional weight directly impacts vehicle range. With the continued introduction of many new sensors and with forecasts showing up to 22 billion automotive sensors in 2020, this problem is only worsening. Any technology that can reduce the weight and cost of the cable harness is to be welcomed and offers significant appeal to automotive OEMs.
To address this, Analog Devices, Inc. (ADI) has developed a new car camera link technology called Car Camera Bus (C2B™), one of the only technologies optimized solely for the car camera link and that addresses the issues described above. C2B encompasses three main solution-defining criteria:
- Offering the easiest upgrade path to HD by reusing existing SD unshielded twisted pair (UTP) cable and connector infrastructure.
- Supporting high definition video with excellent visual quality using this infrastructure.
- Meeting all automotive EMI/EMC requirements using this infrastructure.