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In addition to the desired frequency, theoretically the Time Modulated Antenna Array (TMAA) radiates signals at the infinite number of different harmonics of the modulation frequency. But the radiation energy at the first few harmonics (called sidebands) is most significant. In this paper, the maximum radiation at first two harmonics of TMAA has been studied for the different values of the side lobe...
Linear Antenna Arrays are the simplest and most popular type of antenna arrays. In this paper, symmetric linear array structures, with and without centre element are assumed. Simulated results reveal, non-uniform location profile and non-uniform excitation distribution can provide low and decreasing sidelobe and narrow first null beamwidth. Low tapering of excitation moreover restricts the directivity...
Circular Array is one of the most widely used antenna array designs. Its applications include radio direction finding, air and space navigation, underground propagation, radar, sonar, and many other applications. A broadside uniform circular array radiates (receives) not only in the broadside direction, but, in the other directions as well. Such an array has a significant power loss due to along resting...
Circular antenna array has gained immense popularity in the field of communications nowadays. It has proved to be a better alternative over other types of antenna array configuration due to its all-azimuth scan capability, and a beam pattern which can be kept invariant. This paper is basically concerned with the thinning of a large multiple concentric circular array antennas of uniformly excited isotropic...
Circular antenna array has gained immense popularity in the field of communications. It has been proved to be a better alternative over other types of antenna array configurations due to its all-azimuth scan capability, and a beam pattern which can be kept invariant. This paper is basically concerned with the thinning of a large multiple concentric circular ring arrays of uniformly excited isotropic...
Sparse arrays are popular in sonar, ultrasonic imaging and other acoustic equipment. For inter-element spacing larger than one wave length, there will be grate lobes for ordinary sparse array. Using genetic algorithm to optimize array with randomly spaced elements to suppress the grate lobes is introduced in this paper. Fitness function design and variable choosing method for genetic algorithms application...
This study proposes an intelligent real-time odor monitoring system for monitoring odor problems, a new type of environmental problems, in real-time and for managing harmful substances. This system minimizes the measurement error of individual sensors by building a gas sensor array integrating 8 sensors, and applies a pattern recognition algorithm revised for accurate data analysis. The revised pattern...
Phase quantization errors appear in phased array antenna utilizing the digital phase shifter for beam steering. And this cause relatively high parasitic side-lobes. This paper demonstrates the application of genetic algorithm (GA) in reducing the phased quantization errors effects on parasitic side-lobe level of phased array antenna. GA has the ability to escape from local minima and maxima and is...
With the infinitely long current filament as the probe, the application of cosine window function with the parameters optimized by Genetic Algorithm (GA) in plane-wave synthesis technique is studied by the method of computer simulation. Cosine window function with the parameters optimized by GA is utilized to weight the amplitude and phase distribution of the linear array made up of the infinitely...
This paper presents a genetically evolved antijamming beamforming array. The performance of a genetic algorithm (GA) is evaluated in situ as part of a hardware-in-the-loop optimization system. The GA was able to find reasonable beamformer settings to thwart a maximum of three stationary jammers while allowing reception of a signal of interest. Although the array operates in the 2.4 GHz 802.11g band,...
Genetic Algorithm and Association Rules both are commonly used methods in data mining. In this paper, a brief overview of Genetic Algorithm and Association Rules has been given, and this paper has presented an improved extract method of association rules of genetic algorithm based on their respective advantages and disadvantages. It also did some research on designing encoding methods, structuring...
This paper extends an accuracy-based Learning Classifier System (XCS) to promote a generalization of classifiers by selecting effective ones and deleting ineffective ones, and calls it Identification-based XCS (IXCS). Through the intensive simulations of the Maze problem (Maze6), the following implications have been revealed : (1) IXCS can derive good solutions with a fewer number of classifiers in...
The road network of a small town is represented by a directed graph. Road junctions are the vertices of this graph and each road segment (which has a length and a priority value) is represented by a directed edge. Priority values are numbers 1, 2, etc. with the assumption that 1 is the highest priority. We seek to compute an optimal route map that begins at a particular vertex (the depot) and covers...
The paper provides the method of the improved genetic neural network for image segmentation. The method uses improved genetic algorithm BP neural network weights and thresholds to optimize, and use the definition of bipolar fitness function mapping compression to speed up neural network training speed, and then use iterative improved neural network algorithm to achieve image segmentation. The results...
The suppression of random interference nulling for uniform circular array using an improved binary coding method is investigated in this paper, which is based on Genetic Algorithm (GA) applied to smart antenna beamforming. The code lengths of the algorithm's least amplitude significant bits and least phase significant bits are analyzed, and their impacts on algorithm's performance are discussed. As...
In this paper, the data of the teaching evaluation system is optimized by multi-objective optimization to achieve the purpose of teaching evaluation. The data in the database is a significant reduction in the retrieval process by multi-objective. From the actual results, the data after the multi-objective optimization easy to teaching evaluation, to achieve the desired results.
The design method of new planar waveguide-slot array antenna with a centre hole is presented in the paper. Throughout analyzing the effects on patterns sidelobes in the waveguide-slot array antenna with a centre hole, the array's patterns is optimized by Genetic Algorithm method. The results of design are good and compare very well with ones analyzed by the emulational software of the electromagnetic...
This paper presents an intelligent-based algorithm for sizing grid-connected photovoltaic (GCPV) system using Genetic Algorithm (GA). GA had been used to determine the optimal PV module and inverter from pre-developed PV module and inverter databases such that the expected technical performance of the design could be optimized. In addition, the technical sizing outputs such as the number of photovoltaic...
In order to solve the problems such as blindfold search, slower convergence, and sometimes unsuccessfully search in the present genetic algorithms used for intelligent test paper generation, this paper introduces an improved genetic algorithm for intelligent test paper generation. This algorithm generates optimized initial chromosome group and controlling crossing and variation recurring to test paper...
On the basis of multiple transport mode selection, the paper presents the route optimization model for single-task from one origination to several destinations in the fourth party logistics, and gives the solution of Genetic Algorithms. In the algorithms, a length-variant encoding scheme of round number is adopted to represent the selected route, and idea that keeps the best individual is used. The...
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