Hyundai Mobis Co., South Korea's biggest auto parts maker, said Thursday it has invested $4 million in US radar startup Zendar to develop autonomous driving technologies.

Through the stake investment, Hyundai Mobis aims to develop imaging radar optimized for Level 4 autonomous driving technology, the company said in a statement.

Imaging radar extends existing radar's ability beyond detecting bulky objects to recognizing a vehicle's environment more precisely by processing data from radars on the vehicle.

Radar is one of three core technologies that enable autonomous vehicles to see, together with light detection and ranging (LiDAR), and cameras.

In recent years, Hyundai Mobis has increased investments in overseas startups with advanced future mobility technologies, as it seeks to take the lead in next-generation vehicles.

The company set up a $4 billion joint venture with Ireland-based autonomous vehicle startup Aptiv this year to develop a self-driving platform.

It also invested $50 million in US LiDAR company Velodyne Lidar for autonomous driving technologies to mass-produce Level 3 autonomous driving systems by 2021.

A Level 3 car allows lane changes and other autonomous driving functions to work without intervention by the driver.

At Level 4, a vehicle can drive itself under limited conditions and will not operate if all required conditions are not satisfied. At Level 5, a vehicle's automated driving features can drive under any conditions.

Hyundai Mobis introduced Level 4 self-driving automation technology in its concept M.VISION at the Consumer Electronics Show in 2020.

Hyundai Mobis is a key affiliate of Hyundai Motor Group, which has Hyundai Motor Co. and Kia Corp. under its wing. (Yonhap)