Shared Aperture Multibeam Forming of Time-Modulated Linear Array

A novel technique is proposed in this paper for shared aperture multibeam forming in a complex time-modulated linear array. First, a uniform line array is interleaved randomly to form two sparse array subarrays. Subsequently, the theory of time modulation for linear arrays is applied in the constructed subarrays. In the meantime, the switch-on time sequences for each element of the two subarrays are optimized by an optimized differential evolution (DE) algorithm, i.e., the scaling factor of the sinusoidal iterative chaotic system and the adaptive crossover probability factor are used to enhance the diversity of the population. Lastly, the feasibility of the new technique is verified by the comparison between this technique and the basic multibeam algorithm in a shared aperture and the algorithm of iterative FFT. The results of simulations confirm that the proposed algorithm can form more desired beams, and it is superior to other similar approaches.

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Micro Non-Uniform Linear Array (MNULA) for Ultrasound Plane Wave Imaging

Sensors ◽

10.3390/s21020640 ◽

2021 ◽

Vol 21 (2) ◽

pp. 640

Author(s):

Yujia Tang ◽

Zhangjian Li ◽

Yaoyao Cui ◽

Chen Yang ◽

Jiabing Lv ◽

...

Keyword(s):

Plane Wave ◽

Linear Array ◽

Near Field ◽

Uniform Linear Array ◽

Imaging Technology ◽

Linear Arrays ◽

Imaging Quality ◽

Imaging Results ◽

Wave Imaging ◽

Laboratory Technology

Ultrasound plane wave imaging technology has been applied to more clinical situations than ever before because of its rapid imaging speed and stable imaging quality. Most transducers used in plane wave imaging are linear arrays, but their structures limit the application of plane wave imaging technology in some special clinical situations, especially in the endoscopic environment. In the endoscopic environment, the size of the linear array transducer is strictly miniaturized, and the imaging range is also limited to the near field. Meanwhile, the near field of a micro linear array has serious mutual interferences between elements, which is against the imaging quality of near field. Therefore, we propose a new structure of a micro ultrasound linear array for plane wave imaging. In this paper, a theoretical comparison is given through sound field and imaging simulations. On the basis of primary work and laboratory technology, micro uniform and non-uniform linear arrays were made and experimented with the phantom setting. We selected appropriate evaluation parameters to verify the imaging results. Finally, we concluded that the micro non-uniform linear array eliminated the artifacts better than the micro uniform linear array without the additional use of signal processing methods, especially for target points in the near-field. We believe this study provides a possible solution for plane wave imaging in cramped environments like endoscopy.

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Minimal Redundancy Linear Array and Uniform Linear Arrays in Future 5G Smart Devices for Machine-to-Machine Talk

SSRN Electronic Journal ◽

10.2139/ssrn.3878674 ◽

2021 ◽

Author(s):

Satyanand Singh

Keyword(s):

Linear Array ◽

Smart Devices ◽

Machine To Machine ◽

Linear Arrays ◽

Minimal Redundancy

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Research on the Optimization of the Numerical Value Based on Improved Genetic Algorithm

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.333-335.1256 ◽

2013 ◽

Vol 333-335 ◽

pp. 1256-1260

Author(s):

Zhen Dong Li ◽

Qi Yi Zhang

Keyword(s):

Genetic Algorithm ◽

Genetic Algorithms ◽

Adaptive Genetic Algorithm ◽

Improved Genetic Algorithm ◽

Adaptive Genetic Algorithms ◽

Crossover Probability ◽

Adaptive Crossover ◽

Searching Ability ◽

New Algorithms ◽

Relevance Index

For the lack of crossover operation, from three aspects of crossover operation , systemically proposed one kind of improved Crossover operation of Genetic Algorithms, namely used a kind of new consistent Crossover Operator and determined which two individuals to be paired for crossover based on relevance index, which can enhance the algorithms global searching ability; Based on the concentrating degree of fitness, a kind of adaptive crossover probability can guarantee the population will not fall into a local optimal result. Simulation results show that: Compared with the traditional cross-adaptive genetic Algorithms and other adaptive genetic algorithm, the new algorithms convergence velocity and global searching ability are improved greatly, the average optimal results and the rate of converging to the optimal results are better.

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Optimization Design of Structure and Parameters for RBF Neural Network Using Hybrid Hierarchy Genetic Algorithm

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.951.274 ◽

2014 ◽

Vol 951 ◽

pp. 274-277 ◽

Cited By ~ 2

Author(s):

Xu Sheng Gan ◽

Can Yang ◽

Hai Long Gao

Keyword(s):

Neural Network ◽

Genetic Algorithm ◽

Optimization Design ◽

Rbf Neural Network ◽

Hybrid Genetic Algorithm ◽

Proposed Model ◽

Crossover Probability ◽

Ga Algorithm ◽

The Hierarchical Structure ◽

Adaptive Crossover

To improve the optimization design of Radial Basis Function (RBF) neural network, a RBF neural network based on a hybrid Genetic Algorithm (GA) is proposed. First the hierarchical structure and adaptive crossover probability is introduced into the traditional GA algorithm for the improvement, and then the hybrid GA algorithm is used to optimize the structure and parameters of the network. The simulation indicates that the proposed model has a good modeling performance.

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An Improved Hierarchical Genetic Algorithm for Sheet Cutting Scheduling with Process Constraints

The Scientific World JOURNAL ◽

10.1155/2013/202683 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10

Author(s):

Yunqing Rao ◽

Dezhong Qi ◽

Jinling Li

Keyword(s):

Genetic Algorithm ◽

Parallel Machines ◽

Convergence Rates ◽

Cutting Stock ◽

Hierarchical Coding ◽

Crossover Probability ◽

Speed Up ◽

Adaptive Crossover ◽

Process Constraints ◽

Hierarchical Genetic Algorithm

For the first time, an improved hierarchical genetic algorithm for sheet cutting problem which involvesncutting patterns formnon-identical parallel machines with process constraints has been proposed in the integrated cutting stock model. The objective of the cutting scheduling problem is minimizing the weighted completed time. A mathematical model for this problem is presented, an improved hierarchical genetic algorithm (ant colony—hierarchical genetic algorithm) is developed for better solution, and a hierarchical coding method is used based on the characteristics of the problem. Furthermore, to speed up convergence rates and resolve local convergence issues, a kind of adaptive crossover probability and mutation probability is used in this algorithm. The computational result and comparison prove that the presented approach is quite effective for the considered problem.

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Interfacing a Line Array Camera to the BBC Microcomputer

International Journal of Electrical Engineering Education ◽

10.1177/002072098702400409 ◽

1987 ◽

Vol 24 (4) ◽

pp. 337-345 ◽

Cited By ~ 1

Author(s):

A. E. Adams ◽

M. P. Brammer

Keyword(s):

Linear Array ◽

Low Cost ◽

Image Data ◽

Grey Level ◽

Line Array ◽

Array Camera

A low cost design is described which enables the capture of images from a 256-element CCD linear array camera. The image data is stored in a BBC microcomputer and the microcomputer's screen used for the display of grey level images.

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Part I. A continuous configuration hydrophone array for broadband continuous seismic profiling : Part II. A comparison between the responses of a continuous line array and a discrete linear array

10.1575/1912/25255 ◽

1969 ◽

Author(s):

Sydney T. Knott ◽

Richard T. Nowak

Keyword(s):

Linear Array ◽

Continuous Line ◽

Seismic Profiling ◽

Line Array ◽

Hydrophone Array

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Application of time modulation in the synthesis of sum and difference patterns by using linear arrays

Microwave and Optical Technology Letters ◽

10.1002/mop.21489 ◽

2006 ◽

Vol 48 (5) ◽

pp. 829-832 ◽

Cited By ~ 73

Author(s):

J. Fondevila ◽

J. C. Brégains ◽

F. Ares ◽

E. Moreno

Keyword(s):

Linear Arrays ◽

Time Modulation

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Optimizing uniformly excited linear arrays through time modulation

IEEE Antennas and Wireless Propagation Letters ◽

10.1109/lawp.2004.838833 ◽

2004 ◽

Vol 3 ◽

pp. 298-301 ◽

Cited By ~ 165

Author(s):

Fondevila ◽

Bregains ◽

Ares ◽

Moreno

Keyword(s):

Linear Arrays ◽

Time Modulation

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Synthesis of Sparse Concentric Ring Arrays Based on Fitness-Associated Differential Evolution Algorithm

International Journal of Antennas and Propagation ◽

10.1155/2019/4583268 ◽

2019 ◽

Vol 2019 ◽

pp. 1-17

Author(s):

Xujian Wang ◽

Minli Yao ◽

Fenggan Zhang ◽

Dingcheng Dai

Keyword(s):

Differential Evolution ◽

Differential Evolution Algorithm ◽

Population Diversity ◽

Concentric Ring ◽

Exploration Process ◽

De Algorithm ◽

Crossover Probability ◽

Negative Effect ◽

Evolution Algorithm ◽

Enrich Population

In this paper, fitness-associated differential evolution (FITDE) algorithm is proposed and applied to the synthesis of sparse concentric ring arrays under constraint conditions, whose goal is to reduce peak sidelobe level. In unmodified differential evolution (DE) algorithm, crossover probability is constant and remains unchanged during the whole optimization process, resulting in the negative effect on the population diversity and convergence speed. Therefore, FITDE is proposed where crossover probability can change according to certain information. Firstly, the population fitness variance is introduced to the traditional differential evolution algorithm to adjust the constant crossover probability dynamically. The fitness variance in the earlier iterations is relatively large. Under this circumstance, the corresponding crossover probability shall be small to speed up the exploration process. As the iteration progresses, the fitness variance becomes small on the whole and the crossover probability should be set large to enrich population diversity. Thereby, we construct three variation strategies of crossover probability according to the above changing trend. Secondly, FITDE is tested on benchmark functions, and the best one of the three strategies is determined according to the test results. Finally, sparse concentric ring arrays are optimized using FITDE, of which the results are compared with reference algorithms. The optimization results manifest the advantageous effectiveness of FITDE.

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