Video decoder for automotive cameras enables economical surround view applications

Renesas Electronics Corporation offers the newest device in its Automotive HD Link (AHL) portfolio, enabling automotive manufacturers to deliver high-definition video over low-cost cables and connectors. The new RAA279974 four-channel AHL video decoder processes four input sources simultaneously, making it an economical solution for surround-view and multi-camera applications.

The company’s AHL technology uses a modulated analog signal to transmit video. The frequency is, therefore, ten times lower than digital transmission solutions available today (-37MHz vs>3GHz), making it robust against noise and allowing longer transmission distances (20-30m) with unshielded twisted pair cables and standard connectors. Existing standard-definition analog video cables and connectors can also be employed. Utilising unshielded twisted pair cables not only lowers cost but also makes it easier to route through the vehicle and provides lighter weight for improved energy efficiency and performance. Digital links such as SerDes need heavily shielded cables and high-end connectors that cost greatly more than those for AHL and may need replacement after five to seven years.

The decoder completes the AHL family of products, which consists of the RAA279971, single channel AHL video encoder and the RAA279972, a single-channel AHL video decoder. The device is an important addition to the AHL family as most OEMs want to support multiple vehicle cameras for applications such as surround-view parking assistance monitors. AHL can be paired with R-Car Automotive SoCs, RH850 MCUs, automotive PMICs, and analog components to implement numerous safety features in virtually any vehicle cost-effectively. The company supplies multiple Winning Combinations that combine these components, allowing manufacturers to implement pre-tested video designs quickly.

“Multi-camera safety systems are quickly becoming a must-have feature for many consumers,” said Davin Lee, vice president of the Analog and Connectivity Product Group. “The AHL system enables our automotive customers to now deliver these features in all new vehicles, including economy models.”

AHL is robust against noise and offers excellent picture quality. There is no discernible difference in picture quality compared to a pure digital video image. Due to the fundamental nature of an analog signal, an AHL video transmission can withstand noise and interference. The picture may degrade slightly, but a live image will still be available to view. With a digital link, any noise/interference will result in a complete loss of picture.

The four-channel decoder samples and evaluation boards are available now. The company also offers the RTKA279974ZK0000BU Camera Kit Bundle evaluation system, which includes four AHL cameras integrated with the RAA279971 AHL encoder.