China’s award-winning submarine radar can ‘fish for a needle in the sea’

A Chinese radar research team’s scientific paper that took a deep dive of underwater discovery has been recognised in this year’s awards from the international journal Applied Optics.

The study, which stood out among 1,278 submissions to the journal’s Best Paper Prize in October, introduced a radar technology that can detect objects at great depths, a process that has been likened to “fishing for a needle in the sea”.

In the 2023 paper, the researchers, led by Xiamen University associate professor Shangguan Mingjia, unveiled the world’s first single-photon Raman lidar system, capable of operating at 1,000 metres (about 3,280 feet) below sea level.

Short for “light detection and ranging”, lidar sensors use lasers to measure the distance to objects.

The highly sensitive, low-noise single-photon detector beats the significant size and power consumption challenges of oceanic lidar systems and is also suitable for lowlight conditions.

Meanwhile, Raman scattering – the phenomenon of laser light interacting with materials to produce vibrational changes – can help to identify substances such as oil and dissolved CO2, according to the paper.