With the increasing popularity of high-level autonomous driving, LiDAR as its core device, which ensures driving comfort and safety, is receiving more and more attention. High-performance, small-size, low-cost, low-power, high-safety LiDAR is the direction that manufacturers will be competing for in the future. Based on two years of research, Professor Wang Xingjun's group - Researcher Chang Lin's group in the School of Electronics at Peking University has developed a new multi-channel chaotic light source on silicon substrate, proposed a parallel LIDAR architecture based on chaotic light comb, and overcame the two worldwide problems of LIDAR anti-jamming and high-precision parallel detection, which ensures high performance and high safety, and at the same time, greatly reduces the volume, complexity, power consumption and cost of future LIDAR systems.
The team's research result, "Breaking the temporal and frequency congestion of LiDAR by parallel chaos," is published in the March 13, 2023 issue of Nature Photonics journal.
Screenshot of the paper
The research team generates natural multi-channel random modulated signals by integrating the modulation instability of microcavity optical combs, whose signal chaotic bandwidth can exceed 7 GHz, and the modulation instability of the optical combs shows good robustness within the detuning range of 18 GHz, which can cope with the frequency jitter of the externally pumped light source. At the same time, the high nonlinear coefficient of the material enables the threshold power of the resulting modulation-unstable optical combs to be 1-2 orders of magnitude lower compared to other material platforms, enabling co-integration with on-chip DFB lasers. On this basis, the research team built a parallel LiDAR demonstration system and performed high-precision 3D imaging of physical targets, verified single-pixel imaging at 10-channel scale, and demonstrated good orthogonal isolation between channels. In addition, the research team also tested the anti-noise power suppression ratio of the received signal under different signal interference mixing. The measured power dynamic range of the single signal is close to 60dB under the 3dB threshold criterion and 12.5μm integration time, the anti-noise power suppression ratio of the FM continuous wave signal is close to 30dB, and the anti-noise power suppression ratio of the self-modulated random signal is 22dB, which shows a good active anti-interference capability. The above results are expected to promote changes in the next generation of high-performance interference-resistant LiDAR.
Integrated Parallel Chaotic Lidar System Architecture
The co-first authors of the paper are Ruixuan Chen, a postdoctoral fellow at the Center's Boya, Haowen Shu, a PhD student, Bitao Shen, and Chang Lin, a researcher. Prof. Xingjun Wang of the Center, Prof. John E. Bowers of the University of California, Santa Barbara, and Researcher Chang Lin are the corresponding authors of the paper. The main collaborators also include Dr. Wei-Qiang Xie of University of California, Santa Barbara (now an associate professor at Shanghai Jiao Tong University), Wenchao Liao, a postdoctoral fellow at the center, and Zihan Tao, a PhD student. This work was performed by the State Key Laboratory of Regional Optical Fiber Communication Networks and Novel Optical Communication Systems, School of Electronics, Peking University as the first unit.
The research team has also made a number of important advances in integrated optoelectronics in recent years, including the realization of high-capacity optical communication and high-precision microwave photonic signal processing across the C-V band on Tb/s silicon substrate (Nature2022), lithium niobate integrated photonic chip (Science2022), 1.04 TOPS/mm2 high-computing power density on-chip optical computing (Nature Communication2023), 30nm very small particle size virus detection (Nature Communication2021), 36μm lowest power threshold optical frequency comb light source (Nature Communication2020) and many other international leading achievements. The research results were also honored with the 2022 China Top 10 Science and Technology Innovation Award, the 2022 China Top 10 Advances in Optics, the 2022 China Top 10 Social Influence Events in Optics and so on.
The above results were supported by the Key Research and Development Program of the Ministry of Science and Technology, the National Natural Science Foundation of China and the Beijing Municipal Science and Technology Commission.
Link to the original relevant paper:
1、https://www.nature.com/articles/s41586-022-04579-3
2、https://www.science.org/doi/10.1126/science.abj4396
3、https://www.nature.com/articles/s41467-022-35506-9
4、https://www.nature.com/articles/s41467-021-22271-4
5、https://www.nature.com/articles/s41467-020-15005-5
