Solution for automotive cameras enables high-definition video

Renesas Electronics Corporation has introduced its new Automotive HD Link (AHL) technology that facilitates automotive manufacturers to produce high-definition video over low-cost cables and connectors that currently support standard-definition video. HD video is increasingly essential in-car safety systems for object recognition functionality. AHL can be paired with its other products, such as the R-Car Automotive SoCs, RH850 MCUs, automotive PMICs, and analog components, to cost-effectively implement multiple safety features in practically any vehicle.

The new RAA279971 AHL encoder and RAA279972 decoder employ a modulated analog signal to transmit the video, enabling transmission rates ten times less than needed to transmit HD signals digitally. The lower transmission rate signifies that conventional twisted-pair cables and standard connectors can be employed, as can existing analog video cables and connectors. On the other hand, digital links such as SerDes need heavily shielded cables, and high-end connectors that cost far more than those for AHL may need replacement after five to seven years and are challenging to route due to bending radius limitations.

AHL is strong against noise and has a bi-directional control channel that functions independent of the video data and can initialise, program, and monitor the camera module. A key AHL performance and the cost-reducing feature can control the camera simultaneously over the same pair of wires (UTP) throughout video transmission. Another safety benefit is its performance in comparison to a digital link. In a rearview camera application, a digital link will degrade due to a failure in the cable harness or connector assembly, as weak signals can create macroblocks to appear, hiding large portions of the viewing area. Utilising the same cable under the same conditions for comparison, the AHL link will present a slight change in video colour or contrast. Still, all pixels will appear on the screen, and the image will precisely identify an object or person behind the vehicle.

“Advanced safety systems are no longer only available in luxury vehicles,” said Niall Lyne, vice president of the Automotive Analog Power and Video Business Division at Renesas. “The AHL system enables our automotive customers to now deliver these features in all new vehicles, including economy models.”