在PLC無源芯片方面，承擔了國家重點研發項目“無源光電子材料與器件研究”和河南省重大引領專項“高速數據中心光互連芯片研發及產業化”，開展了石英基、硅基二氧化硅AWG芯片關鍵技術研究，研制出4通道、O波段CWDM、LAN AWG芯片，解決了小尺寸、平坦寬帶響應設計及工藝中互溶回流退火關鍵問題，通過了英特爾、索爾思及AOI等認證。
如圖1所示為一個N×N的AWG結構示意圖，其由N條輸入波導，N條輸出波導，兩個聚焦平板波導（自由傳播區）和陣列波導等五個部分組成。輸入輸出波導的位置和陣列波導的位置均滿足羅蘭圓原理，即各輸入/輸出波導連接自由傳播區的一端以一定的中心間距Δx均勻地排列在一個羅蘭圓圓周上，陣列波導連接自由傳播區的一端則以一定的中心間距d分布在光柵圓圓周上。光柵圓的半徑為R，也稱為自由傳播區的聚焦半徑。羅蘭圓起到凹面光柵的聚焦功能的作用，陣列波導的中心位于光柵圓與羅蘭圓的切點處，相鄰陣列波導保持特定的長度差ΔL。
AWG結構具有波分復用和解復用功能，以波分解復用功能為例，說明AWG的工作原理：復用光波耦合進入AWG的輸入波導，在平板波導內衍射，并耦合進陣列波導區，因陣列波導端面位于光柵圓周上，所以衍射光以相同相位到達陣列波導端面，相同相位的衍射光，經長度差為L的陣列波導傳輸后，產生了相位差（不同波長的相位差也不同），于是，不同波長的光波被輸出平板波導聚焦到不同的輸出波導位置，即完成了解復用功能；如果光逆向輸入，則實現復用功能，即合波功能，原理相同。AWG是無源合波器最常用的結構，本研究的無源合波器均采用AWG結構。
下面從AWG滿足的光柵方程來分析其波分（解）復用功能。根據多光束干涉原理，AWG的光柵方程為：
Researchers employed the CTDE in two scenarios, predictions with baseline dataset and predictions with longitudinal dataset, to predict the scores with the dataset obtained from ADNI (Alzheimer’s disease Neuroimaging Initiative) database.
The results demonstrated that the combination of correntropy regularized joint learning and DPN promoted the advantages of each other in the sense of increasing the prediction accuracy and discovering AD biomarkers.
The comparisons experiment between the CTDE and state-of-the-art methods showed that the proposed CTDE model achieved the best performance.
"One key advantage of our framework is that we utilized all the previous time points dataset to obtain the predicted scores at the next time point, which can improve the score prediction’s accuracy,” said Prof. WANG Shuqiang, “but still, other relevant clinical details, such as gender, education level and physiological factors of AD were not taken into account in this experiments. For further improving the clinical scores prediction performance, we will try to conduct more sophisticated feature selection and encoding methods in the next step.”
The study has published in Pattern Recognition.
