The optimal imaging time selection of ship targets for shore-based inverse synthetic aperture radar （ISAR） in high sea conditions is investigated. The optimal imaging time includes opti- mal imaging instants and opt...The optimal imaging time selection of ship targets for shore-based inverse synthetic aperture radar （ISAR） in high sea conditions is investigated. The optimal imaging time includes opti- mal imaging instants and optimal imaging duration. A novel method for optimal imaging instants selection based on the estimation of the Doppler centroid frequencies （DCFs） of a series of images obtained over continuous short durations is proposed. Combined with the optimal imaging duration selection scheme using the image contrast maximization criteria, this method can provide the ship images with the highest focus. Simulated and real data pro- cessing results verify the effectiveness of the proposed imaging method.展开更多
In optical systems,it is necessary to investigate the propagation of optical solitons in optical fiber systems for fiber-optic communications.By means of the bilinear method,we obtain the two-soliton solution of the v...In optical systems,it is necessary to investigate the propagation of optical solitons in optical fiber systems for fiber-optic communications.By means of the bilinear method,we obtain the two-soliton solution of the variable coefficient higher-order coupled nonlinear Schrodinger equation.According to the obtained two-soliton solution,a novel two-soliton interaction structure of the system is constructed,and their interactions are studied.Two optical solitons occur with elastic interaction under certain conditions,and their amplitudes,shapes and velocities remain unchanged before and after the action.In addition to the elastic interaction,splitting action and polymerization also occur.The present study on the dynamic behavior of interaction of optical solitons may be valuable for research and applications in optical communication and other fields.展开更多
基金supported by the Innovation Foundation for Scientific Research Base(NJ20140008NJ20150018)+1 种基金the Aeronautical Science Foundation of China(20132052035)the National Defense Basic Scientific Research(B2520110008)
文摘The optimal imaging time selection of ship targets for shore-based inverse synthetic aperture radar （ISAR） in high sea conditions is investigated. The optimal imaging time includes opti- mal imaging instants and optimal imaging duration. A novel method for optimal imaging instants selection based on the estimation of the Doppler centroid frequencies （DCFs） of a series of images obtained over continuous short durations is proposed. Combined with the optimal imaging duration selection scheme using the image contrast maximization criteria, this method can provide the ship images with the highest focus. Simulated and real data pro- cessing results verify the effectiveness of the proposed imaging method.
基金supported by the National Natural Science Foundation of China(Grant Nos.11875009 and 11905016)。
文摘In optical systems,it is necessary to investigate the propagation of optical solitons in optical fiber systems for fiber-optic communications.By means of the bilinear method,we obtain the two-soliton solution of the variable coefficient higher-order coupled nonlinear Schrodinger equation.According to the obtained two-soliton solution,a novel two-soliton interaction structure of the system is constructed,and their interactions are studied.Two optical solitons occur with elastic interaction under certain conditions,and their amplitudes,shapes and velocities remain unchanged before and after the action.In addition to the elastic interaction,splitting action and polymerization also occur.The present study on the dynamic behavior of interaction of optical solitons may be valuable for research and applications in optical communication and other fields.
