To gain the tradeoff between lower sidelobe and higher power amplifiers efficiency,a transmitting beam shaping scheme with limited amplitude weight values for satellite active phased array antenna is presented. The sc...To gain the tradeoff between lower sidelobe and higher power amplifiers efficiency,a transmitting beam shaping scheme with limited amplitude weight values for satellite active phased array antenna is presented. The scheme is implemented by a dual coding genetic algorithm(GA). Phase and amplitude of array weight vectors for beam shaping are encoded by real coding and finite length binary coding,respectively,which,maintaining accuracy of results,reduces the amplitude dynamic range and improves the efficiency of power amplifiers. The presented algorithm,compared with complex-coded GA,increases the convergence rate due to the search space's decrease. In order to overcome the prematurity and obtain better global optimization or quasi-global optimization,a new dual coding GA based on "species diversity retention" strategy and adaptive crossover and mutation probability are presented.展开更多
The properties of the linear chirped fiber grating （CFG） which is used in the true time delay unit of the optical beamforming networks （OBFNs） are studied intensively through theoretical analyses and numerical cal...The properties of the linear chirped fiber grating （CFG） which is used in the true time delay unit of the optical beamforming networks （OBFNs） are studied intensively through theoretical analyses and numerical calculations. It is concluded that the dispersion of the CFG is equal to 1/（3Gc）, where G is the chirp coefficient of CFG and c is the light speed. Based on this relationship, a simplified designing process of a CFG which satisfies the requirements of the O13 FN is given. The simula- tion results are coincident with the theoretical conclusions.展开更多
基金The project supported by National Natural Science Foundation of China (No. 60572095)Research Foundation for Doctors of ZZULI
文摘To gain the tradeoff between lower sidelobe and higher power amplifiers efficiency,a transmitting beam shaping scheme with limited amplitude weight values for satellite active phased array antenna is presented. The scheme is implemented by a dual coding genetic algorithm(GA). Phase and amplitude of array weight vectors for beam shaping are encoded by real coding and finite length binary coding,respectively,which,maintaining accuracy of results,reduces the amplitude dynamic range and improves the efficiency of power amplifiers. The presented algorithm,compared with complex-coded GA,increases the convergence rate due to the search space's decrease. In order to overcome the prematurity and obtain better global optimization or quasi-global optimization,a new dual coding GA based on "species diversity retention" strategy and adaptive crossover and mutation probability are presented.
基金supported by the National Natural Science Foundation of China (No.60702005)the Hi-Tech Research and Development Program of China (Nos.2009AA01Z218 and 2009AA01Z255)+1 种基金the National Basic Research Program of China (973 Program) (Nos.2010CB328202and 2010CB328204)the Fundamental Research Funds for the Central
文摘The properties of the linear chirped fiber grating （CFG） which is used in the true time delay unit of the optical beamforming networks （OBFNs） are studied intensively through theoretical analyses and numerical calculations. It is concluded that the dispersion of the CFG is equal to 1/（3Gc）, where G is the chirp coefficient of CFG and c is the light speed. Based on this relationship, a simplified designing process of a CFG which satisfies the requirements of the O13 FN is given. The simula- tion results are coincident with the theoretical conclusions.
