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Hua Guo,Chenjiang Guo,Jun Ding 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.4
The optimization of the sum and difference patterns for monopulse antennas by a hybrid real/integer-coded invasive weed optimization (IWO) is introduced in this paper. The whole array aperture is divided into several subarrays. The configuration and weight of each subarray are optimized. In order to reduce the difficulty of designing the feeding networks of the array antenna, the elements of the same subarray stay together. Since only the weight and elements number of each subarray is optimized, the number of the optimized parameters is reduced significantly which will reduce the complexity of the simulation procedure. Several numerical simulations are applied to validate the effectiveness of the proposed approach.
Yan Qu,Chenjiang Guo,Xia Zhao,Wencan Peng,Jun Ding 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.4
Phase-only optimization of asymmetric multiple beams reflectarray with single feed is investigated in this paper. The conventional design approaches are first reviewed. Secondly, for design of asymmetric multiple beams reflectarray with arbitrary gain levels and beam directions, a general method based on invasive weed optimization is proposed. Then, practical considerations for applying the proposed method to design multiple beams reflectarray are talked over. For illustrating the effectiveness of the proposed method, several multiple beams design cases with different design requirements are optimized through this method, and the optimized results are analyzed through simulation approach based on array theory. The simulation results show that the optimized cases demonstrate the satisfactory multiple beams performance.
Design of Single-Feed Multi-Beam Reflectarray Using Iterative Fourier Techniques
Yan Qu,Chenjiang Guo,Hua Guo,Jun Ding 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.4
Reflectarray antenna with multiple simultaneous beams is a promising antenna candidate for the multiple beam applications. A comprehensive and systematic study on the design of single-feed multi-beam reflectarray antenna is presented in this paper. The traditional direct design method, called aperture field superposition method, is investigated first. It is demonstrated that although this method can generate a multi-beam pattern, it cannot provide satisfactory performances, mainly because of high side lobe level, gain loss and beam deviation. The iterative Fourier technique is then applied to optimize the performances of the multi-beam reflectarray antenna. The required mask and cost function for multi-beam design and the flow of the iterative Fourier techniques are represented. Finally, a Ku-band four beam reflectarray with a single feed is designed using the iterative Fourier techniques and the radiation performances are analyzed and compared with that of single beam, as reference case, and multiple beam designed by aperture field superposition. The numerical results show that a good four beam performance can be obtained by using the iterative Fourier techniques, which suggests that the iterative Fourier technique is suitable for the design of the multi-beam reflectarray antenna with a single-feed.
Chen Jiang,Qi Song,Debao Guo,Haolin Li 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.
This work presents an investigation of the minimum dwell time during the precision cylindrical-plunge grinding process. Accordingto the model of acoustic emissions proposed in earlier work, two estimation algorithms of the dwell time, focused on the size errorand the surface roundness of the machined workpiece, are deduced from the models of the material removal and the surfaceroundness, respectively. Based on the proposed estimation algorithms, an on-line estimation method of the minimum dwell time isdeveloped using the measurement and analysis of the acoustic emission signal. A series of experiments of grinding C45 steel areconducted to confirm the validity of the proposed estimation algorithms and determine the model coefficient. The ability of theestimation algorithms to predict the minimum dwell time is deemed necessary for optimal control of the grinding process. In addition,the proposed model provides a new approach to estimate the machined qualities of a workpiece such as the surface roughness andsize error using the dwell time of the grinding process.