The Asia Communications and Photonics Conference (ACP) 2020 was held in Beijing from October 24-27. Hongyan Fu, Associate Professor of the Tsinghua-Berkeley Shenzhen Institute (TBSI), Yuhan Dong, Associate Professor of Tsinghua Shenzhen International Graduate School (SIGS), and their groups attended this flagship conference and presented their latest research progress. Master students Shi Zhang and Zhiyuan Cao won Best Student Paper Award and Best Poster Award, respectively.
Associate Prof. Hongyan Fu and his research group
Associate Prof. Yuhan Dong and his research group
Best Student Paper Award went to Shi Zhang for his work entitled “Gbps Spatial Diversity Visible Light Communication System Using a Pair 75-μm Micro-LED.” A high-speed visible light communication system was implemented based on a pair of blue micro-LEDs designed by collaborators. The work utilized structural illumination to expand the coverage of micro-LED and was able to facilitate communication over 1 Gbps and illumination simultaneously.
Shi Zhang, giving an oral presentation
Best Poster Award went to Zhiyuan Cao for his work entitled “High-speed Long-distance Optical Wireless Communication Based on a 940-nm VCSEL with 4.46-Gbps QAM-OFDM.” He implemented a 12-meter optical wireless communication system by a common commercial VCSEL and achieved a data rate of 4.46 Gbps. The adaptive resource allocation and frequency rectification were adopted to maximize bandwidth utilization and improved anti-interference ability.
Zhiyuan Cao and his poster
Other students also gave fascinating presentations of their research work.
Keming Ma’s work entitled “Impedance Characteristic Study of Packaged InGaN QD-based Micro-LED for Visible Light Communication” analyzed the impedance characteristic of a 50-μm QD-micro-LED designed, fabricated, and packaged by collaborators. He fixed the equivalent circuit model of the QD micro-LED and provided a basis for the comparison of theoretical and practical 3dB bandwidth.
Novel emitting devices such as VCSEL were a highlight of the optical wireless communication section during the conference. Zhaoming Wang’s work entitled “8.23 Gbps High-speed Near-infrared VCSEL Based Facile Optical Wireless Communication System via QAM-OFDM” proposed a potential invisible uplink approach for more than 8 Gbps data rate transmission. This infrared 850nm light is also operated under a relatively low intensity to avoid damage to the human eyes.
Simei Mao’s work entitled “Compact Five-mode De-multiplexer based on Grating Assisted Asymmetric Directional Couplers” proposed a 25-μm five-mode de-multiplexer based on subwavelength grating directional couplers with constant bus waveguide. The insertion loss was less than 0.31 dB at 1550 nm and its 1-dB bandwidth was over 100 nm.
Lirong Cheng’s work entitled "Silicon Photonic Vertical Few-mode Fiber Interface Designed by Adjoint Optimization" proposed a vertical few-mode fiber interface on silicon photonics. Compact mode-size converter and non-uniform grating coupler supporting both LP11a and LP21a modes were demonstrated using adjoint optimization.
Xin Liu’s work entitled “Sequence Detector based Autoencoder for ACO-OFDM Optical Wireless Communication” proposed a novel transceiver scheme for optical wireless communication based on neural network to handle the multipath fading channel. Results showed that the proposed system outperformed conventional quadrature amplitude modulation (QAM) formats and other neural networks over multipath fading channel.
Students from the Fu and Dong groups presented at the ACP conference: (top row, from left) Keming Ma, Zhaoming Wang; (bottom row, from left) Lirong Cheng, Simei Mao, Xin Liu
ACP is currently the largest conference in the Asia-Pacific region on optical communication, photonics and relevant technologies. It has been held annually since 2001 and is jointly sponsored by OSA, SPIE, IEEE Photonics Society, COS and CIC. This year, 8 best student papers and 15 best posters were selected by the ACP technical program committee from a total of 592 accepted papers.
Writers: Shi Zhang, Zhiyuan Cao, Keming Ma, Zhaoming Wang, Simei Mao, Lirong Cheng, Xin Liu
