Researchers at the City University of Hong Kong have designed a tiny new radar chip that could help shape the future of wireless technology. About the size of a small coin, this device is the world’s first fully integrated photonic millimeter-wave radar chip. Despite its compact size, it can deliver extremely precise information about objects and movement in its surroundings. This breakthrough could play a key role in the development of next-generation 6G networks, which are expected to combine communication and sensing in a single system. Radar is commonly used to detect objects, measure distance, and track movement. Today’s radar systems are mostly electronic, which means they rely on electrical signals to send and receive information. These systems often face a trade-off: higher frequencies can give better detail, but they are harder to generate and process. The Hong Kong research team found a way around this problem by using light instead of electricity for much of the process. In this new chip, radar signals are created and processed using optical, or light-based, technology. Light can handle a much wider range of frequencies than traditional electronic systems, which allows the radar to achieve much better resolution. In simple terms, this means the radar can “see” more clearly and detect finer details, such as how far away an object is, how fast it is moving, and even its shape. The device works in what is called the millimeter-wave band, specifically around 45 gigahertz, with a very wide bandwidth. This gives it the ability to perform very precise ranging and speed measurements. It can even carry out advanced imaging techniques that help identify and track objects in complex environments. All of these functions are built into a single chip, which handles both producing the radar signals and analyzing the echoes that bounce back from targets. One of the key innovations behind this chip is the use of a special material called thin-film lithium niobate. This material is well known for its ability to control and guide light very efficiently. The researchers have spent years refining a way to build complex optical circuits using this material, and it is the foundation that makes this miniature radar system possible. Another important advantage is that the design does not require bulky, high-cost components that are normally needed to convert between digital and analog signals at high speeds. That makes the system more affordable and practical. The chip can be made at scale on standard 4-inch wafers, which means it could one day be produced in large quantities for use in real products. In the future, chips like this could allow everyday devices to not only communicate but also understand their surroundings. They could be used in indoor sensing, smart homes, self-driving cars, health monitoring systems, and many other applications. By combining communication and sensing, this tiny radar chip represents a big step toward a more connected and aware 6G world.
https://knowridge.com/2025/11/a-tiny-radar-chip-could-power-the-smart-sensing-world-of-6g/
A tiny radar chip could power the smart sensing world of 6G
