| 2 | Integrated photonic RF self-interference cancellation on a silicon platform for full-duplex communication显示文摘In-band full-duplex(IBFD) technology can double the spectrum utilization efficiency for wireless communications,and increase the data transmission rate of B5G and 6G networks and satellite communications. RF self-interference is the major challenge for the application of IBFD technology, which must be resolved. Compared with the conventional electronic method, the photonic self-interference cancellation(PSIC) technique has the advantages of wide bandwidth, high amplitude and time delay tuning precision, and immunity to electromagnetic interference.Integrating the PSIC system on chip can effectively reduce the size, weight, and power consumption and meet the application requirement, especially for mobile terminals and small satellite payloads. In this paper, the silicon integrated PSIC chip is presented first and demonstrated for IBFD communication. The integrated PSIC chip comprises function units including phase modulation, time delay and amplitude tuning, sideband filtering, and photodetection, which complete the matching conditions for RF self-interference cancellation. Over the wide frequency range of C, X, Ku, and K bands, from 5 GHz to 25 GHz, a cancellation depth of more than 20 dB is achieved with the narrowest bandwidth of 140 MHz. A maximum bandwidth of 630 MHz is obtained at a center frequency of10 GHz. The full-duplex communication experiment at Ku-band by using the PSIC chip is carried out. Cancellation depths of 24.9 dB and 26.6 dB are measured for a bandwidth of 100 MHz at central frequencies of 12.4 GHz and14.2 GHz, respectively, and the signal of interest(SOI) with 16-quadrature amplitude modulation is recovered successfully. The factors affecting the cancellation depth and maximum interference to the SOI ratio are investigated in detail. The performances of the integrated PSIC system including link gain, noise figure, receiving sensitivity, and spurious free dynamic range are characterized. | XIUYOU HAN XINXIN SU MENG CHAO XINDI YANG WEIHENG WANG SHUANGLING FU YICHENG DU ZHENLIN WU MINGSHAN ZHAO | 2023 | Photonics Research2023,11,10: | 1 |
| 4 | Crystal phase engineering of electrocatalysts for energy conversions显示文摘Crystal phase is an intrinsic structural parameter to determine the physicochemical properties and functionalities of materials.The unconventional phases of materials with distinct atomic arrangements from their thermodynamically stable phases have attracted enormous attention.Phase engineering has recently made fruitful achievements in electrocatalysis field to optimize the performance of various electrochemical reactions.In this review,theoretical and experimental advances made in phase engineering of electrocatalysts are summarized.First,we introduce basic understanding on crystal phases of catalysts to show the dialectical relationship between bulk phase and surface catalytic layer,and highlight the multiple functions of phase engineering in catalysis studies.We then describe phase-controlled synthesis of materials through various experimental methods such as wet-chemical method,phase transition,and template growth.As a focus,we discuss the wide usage of phase engineering strategy in different kinds of electrocatalytic materials,and particular emphasis is given to establishment of reasonable crystal phase-activity relationship.Finally,we propose several future directions for developing more desirable electrocatalysts by rational crystal phase design. | Hui Chen Mingcheng Zhang Yanfei Wang Ke Sun Lina Wang Zhoubing Xie Yucheng Shen Xindi Han Lan Yang Xiaoxin Zou | 2022 | Nano Research2022,15,12: | 0 |