A scanning and uniform array architecture with large spacing,low complexity and high scalability is presented for high integration massive array applications.It is constructed by offset phase center elements arranged ...A scanning and uniform array architecture with large spacing,low complexity and high scalability is presented for high integration massive array applications.It is constructed by offset phase center elements arranged in a uniform and regular way,but its spacing can be larger than that of traditional arrays.An ideal model of the offset phase center element is established and its far-field distribution is derived.To suppress grating lobes,the phase center of any element is designed to be movable without changing its physical position.Using genetic algorithm(GA),a new constraint condition limiting the number of phase center changes is proposed to solve the objective function of the minimum values of grating lobes(GLs)and side lobes(SLs).It is shown that the optimal results can be achieved by two changes of phase centers.A multimode circular patch is developed and designed,and characteristics of the offset phase center are analyzed and verified.A prototype array of 12×12 offset phase center elements is implemented based on multi-mode circular patches.Full wave simulation results of radiation patterns show that the level of grating lobes is suppressed at least 7dB with 1.12λ spacing,while the scanning angle is 20°.展开更多
Implementation of a nonlocal multi-qubit conditional phase gate is an essential requirement in some quantum infor- mation processing （QIP） tasks. Recently, a novel solid-state cavity quantum electrodynamics （QED） ...Implementation of a nonlocal multi-qubit conditional phase gate is an essential requirement in some quantum infor- mation processing （QIP） tasks. Recently, a novel solid-state cavity quantum electrodynamics （QED） system, in which the nitrogen-vacancy （NV） center in diamond is coupled to a microtoroidal resonator （MTR）, has been proposed as a poten- tial system for hybrid quantum information and computing. By virtue of such systems, we present a scheme to realize a nonlocal N-qubit conditional phase gate directly. Our scheme employs a cavity input-output process and single-photon interference, without the use of any auxiliary entanglement pair or classical communication. Considering the currently available technologies, our scheme might be quite useful among different nodes in quantum networks for large-scaled QIP.展开更多
针对自由空间光通信(Free Space Optical Communication,FSO)中传统激光定位算法,如质心法、圆拟合法、Hough法等存在定位精度较差、时间较长的问题,提出了一种最大弦长算法,以提高大气湍流信道中激光中心定位效率和FSO链路性能。算法...针对自由空间光通信(Free Space Optical Communication,FSO)中传统激光定位算法,如质心法、圆拟合法、Hough法等存在定位精度较差、时间较长的问题,提出了一种最大弦长算法,以提高大气湍流信道中激光中心定位效率和FSO链路性能。算法首先对图像边缘检测后的边缘像素点进行去干扰处理,而后遍历所有边缘像素点,计算它们之间的距离,并对距离最远的每两像素点的中点累加计数,最后选出累计次数最多的中点作为中心,从而实现对激光中心的精确定位。通过与传统激光定位算法的仿真对比表明:最大弦长定位算法能有效降低激光中心的偏移量,提高定位精度,同时本算法能缩短检测过程的计算时间,提高定位效率,且在相同面积的激光中心掩膜内,本文算法包含的总像素强度更大,综合定位效果更好。展开更多
基金This work was supported by National Natural Science Foundation of China(No.U19B2028).
文摘A scanning and uniform array architecture with large spacing,low complexity and high scalability is presented for high integration massive array applications.It is constructed by offset phase center elements arranged in a uniform and regular way,but its spacing can be larger than that of traditional arrays.An ideal model of the offset phase center element is established and its far-field distribution is derived.To suppress grating lobes,the phase center of any element is designed to be movable without changing its physical position.Using genetic algorithm(GA),a new constraint condition limiting the number of phase center changes is proposed to solve the objective function of the minimum values of grating lobes(GLs)and side lobes(SLs).It is shown that the optimal results can be achieved by two changes of phase centers.A multimode circular patch is developed and designed,and characteristics of the offset phase center are analyzed and verified.A prototype array of 12×12 offset phase center elements is implemented based on multi-mode circular patches.Full wave simulation results of radiation patterns show that the level of grating lobes is suppressed at least 7dB with 1.12λ spacing,while the scanning angle is 20°.
基金Project supported by the National Fundamental Research Program of China(Grant No.2010CB923202)the Fundamental Research Funds for the Central Universities,Chinathe National Natural Science Foundation of China(Grant Nos.61177085,61205117,and 61377097)
文摘Implementation of a nonlocal multi-qubit conditional phase gate is an essential requirement in some quantum infor- mation processing （QIP） tasks. Recently, a novel solid-state cavity quantum electrodynamics （QED） system, in which the nitrogen-vacancy （NV） center in diamond is coupled to a microtoroidal resonator （MTR）, has been proposed as a poten- tial system for hybrid quantum information and computing. By virtue of such systems, we present a scheme to realize a nonlocal N-qubit conditional phase gate directly. Our scheme employs a cavity input-output process and single-photon interference, without the use of any auxiliary entanglement pair or classical communication. Considering the currently available technologies, our scheme might be quite useful among different nodes in quantum networks for large-scaled QIP.
文摘针对自由空间光通信(Free Space Optical Communication,FSO)中传统激光定位算法,如质心法、圆拟合法、Hough法等存在定位精度较差、时间较长的问题,提出了一种最大弦长算法,以提高大气湍流信道中激光中心定位效率和FSO链路性能。算法首先对图像边缘检测后的边缘像素点进行去干扰处理,而后遍历所有边缘像素点,计算它们之间的距离,并对距离最远的每两像素点的中点累加计数,最后选出累计次数最多的中点作为中心,从而实现对激光中心的精确定位。通过与传统激光定位算法的仿真对比表明:最大弦长定位算法能有效降低激光中心的偏移量,提高定位精度,同时本算法能缩短检测过程的计算时间,提高定位效率,且在相同面积的激光中心掩膜内,本文算法包含的总像素强度更大,综合定位效果更好。
