The structure of a microlens array（ MLA） can be formed on copper by an indentation process which is a new manufacture approach we applied here instead of a traditional method to test the material property,thereby wo...The structure of a microlens array（ MLA） can be formed on copper by an indentation process which is a new manufacture approach we applied here instead of a traditional method to test the material property,thereby work time can be saved. Single-indentation and multi-indentation are both conducted to generate a single dimple and dimples array,namely micro lens and MLA. Based on finite element simulation method,factors affecting the form accuracy,such as springback at the compressed area of one single dimple and compressional deformation at the adjacent area of dimples arrays,are determined,and the results are verified by experiments under the same conditions. Meanwhile,indenter compensation method is proposed to improve form accuracy of single dimple,and the relationship between pitch and compressional deformation is investigated by modelling seven sets of multi-indentations at different pitches to identify the critical pitch for the MLA＇s indentation processing. Loads and cross-sectional profiles are measured and analyzed to reveal the compressional deformation mechanism. Finally,it is found that MLA at pitches higher than 1. 47 times of its diameter can be manufactured precisely by indentation using a compensated indenter.展开更多
This paper addresses the issue of the direction of arrival （DOA） estimation under the compressive sampling （CS） framework. A novel approach, modified multiple signal classification （MMUSIC） based on the CS array...This paper addresses the issue of the direction of arrival （DOA） estimation under the compressive sampling （CS） framework. A novel approach, modified multiple signal classification （MMUSIC） based on the CS array （CSA-MMUSIC）, is proposed to resolve the DOA estimation of correlated signals and two closely adjacent signals. By using two random CS matrices, a large size array is compressed into a small size array, which effectively reduces the number of the front end circuit. The theoretical analysis demonstrates that the proposed approach has the advantages of low computational complexity and hardware structure compared to other MMUSIC approaches. Simulation results show that CSAMMUSIC can possess similar angular resolution as MMUSIC.展开更多
基金Supported by the National Natural Science Foundation of China(51375050)
文摘The structure of a microlens array（ MLA） can be formed on copper by an indentation process which is a new manufacture approach we applied here instead of a traditional method to test the material property,thereby work time can be saved. Single-indentation and multi-indentation are both conducted to generate a single dimple and dimples array,namely micro lens and MLA. Based on finite element simulation method,factors affecting the form accuracy,such as springback at the compressed area of one single dimple and compressional deformation at the adjacent area of dimples arrays,are determined,and the results are verified by experiments under the same conditions. Meanwhile,indenter compensation method is proposed to improve form accuracy of single dimple,and the relationship between pitch and compressional deformation is investigated by modelling seven sets of multi-indentations at different pitches to identify the critical pitch for the MLA＇s indentation processing. Loads and cross-sectional profiles are measured and analyzed to reveal the compressional deformation mechanism. Finally,it is found that MLA at pitches higher than 1. 47 times of its diameter can be manufactured precisely by indentation using a compensated indenter.
基金supported by the National Natural Science Foundation of China(6117119761371045+2 种基金61201307)the Shandong Provincial Natural Science Foundation(ZR2011FM005)the Shandong Provincial Promotive Research Fund for Excellent Young and Middle-aged Scientists(BS2010DX001)
文摘This paper addresses the issue of the direction of arrival （DOA） estimation under the compressive sampling （CS） framework. A novel approach, modified multiple signal classification （MMUSIC） based on the CS array （CSA-MMUSIC）, is proposed to resolve the DOA estimation of correlated signals and two closely adjacent signals. By using two random CS matrices, a large size array is compressed into a small size array, which effectively reduces the number of the front end circuit. The theoretical analysis demonstrates that the proposed approach has the advantages of low computational complexity and hardware structure compared to other MMUSIC approaches. Simulation results show that CSAMMUSIC can possess similar angular resolution as MMUSIC.
