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1.
A linear array antenna design with desired radiation pattern has been presented based on genetic algorithm (GA) approach. Examples of cosecant and flat‐topped beam patterns are illustrated to show the flexibility of GA to solve complex antenna synthesis problems by suitably selecting the fitness function, even with a simple GA. The results have been validated by IE3D electromagnetic simulation. The antenna arrays with different element geometries can also be implemented using the proposed technique. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. 相似文献
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针对复杂战场环境下超短波电台天线接收低信噪比信号能力弱和易受定向干扰的缺陷,结合战场超短波电台不规则分布和位置不能任意改变的特点,提出任意结构天线阵信号接收模型,采用蜂群算法优化阵元相位使得天线阵输出信干噪比最大。假设信噪比为0 dB,干噪比为60 dB,且在平面内随机选取8个阵元,采用蜂群算法优化后输出信干噪比为8.633 dB。与改进差分进化算法、遗传算法和粒子群优化算法相比,分别提高了0.577 dB、1.124 dB和1.543 dB。研究成果可为超短波电台组阵通信提供参考。 相似文献
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Pattern synthesize of conformal array antennas is often a challenging problem. Various optimization algorithms such as genetic, particle swarm optimization (PSO), and invasive weed optimization have already been used for pattern synthesizing of conformal arrays. In this paper, a focused beam is synthesized for a quarter cylindrical conformal array antenna using the PSO algorithm with small computations. The desired pattern is a focused beam at θ = 90° and ? = 45° with 10° beamwidth in elevation and 15° beamwidth in azimuth with ?20 dB side‐lobe level. This method can be used in general for synthesizing arbitrary desired patterns and array geometries. 相似文献
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This article presents a versatile pattern synthesis algorithm for controlling the sidelobe level and nulling region for circular antenna arrays. Nonuniform fast Fourier transform using the min–max interpolation method is utilized to overcome the nonlinear feature of circular arrays. The major advantage of the proposed algorithm is low complexity, which is key for hardware implementation. Moreover, the proposed algorithm functions well in amplitude‐only pattern synthesis, which may be required for low‐cost array systems using attenuators instead of complete amplitude and phase adjustment modules. Additionally, element failure of antenna arrays can be minimized in practical operations by resynthesizing the pattern by using the remaining antennas to achieve satisfactory performance. Simulation results indicate the lower complexity and higher versatility of the proposed algorithm compared with the conventional methods. 相似文献
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A quantized water cycle optimization algorithm for antenna array synthesis by using digital phase shifters 下载免费PDF全文
In this article, a quantized water cycle algorithm (QWCA) is used for the antenna array pattern synthesis with low side‐lobe levels (SLLs) and nulls at desired directions by using four‐bit digital phase shifters. In addition to the standard features as a metaheuristic algorithm, QWCA has an internal quantization mechanism and a precalculated array factor method. The latter provides an accelerated procedure to QWCA under favour of the digitized values that can be stored in a three‐dimensional array. This acceleration is based on the reality that the accessing data in the memory need less time than the usage of the mathematical functions throughout the optimization process. The internal quantization mechanism of QWCA is utilized to achieve digital values matching to the discrete values of the phase shifter instead of the simple rounding up/down routines after optimization. The numerical results showed that QWCA can obtain very good SLLs and null depth levels (NDLs) on the synthesized pattern. Moreover, the results are achieved in remarkably short optimization times. SLL and NDL values obtained by QWCA are also compared with the available literature values. The comparisons reveal that QWCA is able to produce better results than the other compared alternatives. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:21–29, 2015. 相似文献
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In this article, an extended particle swarm optimization (EPSO) algorithm is proposed for designing conformal phased arrays. On the basis of traditional particle swarm optimization (PSO), novel velocity updating mechanism, new exceeding boundary control operator, and global best perturbation are introduced in EPSO to overcome the drawbacks of PSO. To validate the efficiency of the proposed algorithm, both the classical test functions and the scenarios concerning a 1 × 9‐element cylindrical conformal phased array and a 3 × 9(27)‐element cylindrical conformal array with flat‐top shaped‐beam pattern are presented. Simulation results show that the proposed method is superior to genetic algorithm (GA) and PSO when applied to both the classical test functions and the practical problems of conformal antenna array synthesis. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010. 相似文献
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伴随着雷达技术的飞速发展,数字化相控阵天线开始广泛运用于各种相控阵雷达当中;由于数字化相控阵天线的工作原理与传统模拟相控阵天线差异极大,测试方法也发生了根本性的改变,原有的基于普通微波仪表的天线测试系统无法再对数字化相控阵天线进行测试,必须设计新型的数字化相控阵天线测试系统;文章首先介绍了数字化相控阵天线自身的工作原理和测试方法,随后提出了新型数字化相控阵天线测试系统的具体软硬件设计方案,实际应用表明数字化相控阵天线测试系统可以满足各种数字化相控阵天线的测试要求。 相似文献
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This article presents the design of a grid array antenna with pattern reconfigurable ability. Discussion of various factors that affect the radiation pattern is presented. Interdigital structure, which serves as short radiation line of grid array antenna is then introduced to reconfigure radiation pattern. Change of main beam direction is realized via state change of PIN diodes loaded in interdigital structure and variation of feed point. The scanning angle varies from ?33° to +38° and the average gain is about 10 dBi. The proposed antenna was fabricated and measured. Measured results show the proposed antenna possesses good beam‐scanning characteristics and has potential value in long‐distance power supply for various passive nodes. 相似文献
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Interruptions in the regular lattice of a phased array antenna can lead to elevated sidelobe levels in the resulting antenna pattern. A method for reducing the sidelobe level in such an array is presented, based on the use of a genetic algorithm that modifies the element weights in the array. Results are presented for both scanned and unscanned arrays. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007. 相似文献
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Autocorrelation matching method is proposed for phase‐only synthesis of power pattern of planar antenna arrays. This method is based on equating the autocorrelation coefficients of a planar array having a specified amplitude of excitations to those of a conventionally designed planar array. The effectiveness of the proposed method is verified by synthesis of pencil‐beam and flat‐top patterns. 相似文献
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为生成无栅瓣、高空间分辨率的方向图,均匀平面阵列使用的天线单元数量很多,实现难度和成本高。稀疏布阵只需要相对较少的单元数目,会出现旁瓣电平升高、测向模糊等问题。通过对天线阵列特性进行分析,以全向一致、无栅瓣、低旁瓣的高分辨方向图为目标,利用微遗传算法对多重圆环阵列单元的位置参数进行优化,性能分析表明综合出的多重圆环阵列具有方位角对称、旁瓣电平低、起伏小的特点,且该算法优化效率高、收敛速度快。 相似文献
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This article presents an optimization immune algorithm (opt‐IA) for null steering of linear antenna arrays by controlling only the element amplitudes. Nulling of the pattern is also achieved by controlling the phase‐only and the complex weights (both the amplitude and phase) of the array elements. The opt‐IA is a new evolutionary computing algorithm based on the clonal selection principle of immune system. To show the accuracy and flexibility of the proposed opt‐IA, several examples of Chebyshev array pattern with the imposed single, multiple, and broad nulls are given. It is found that the nulling technique based on opt‐IA is capable of steering the array nulls precisely to the undesired interference directions. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. 相似文献
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Phased array antennas using digital phase shifters for beam steering are characterized by beam pointing error. This study proposes a sequential phase feeding algorithm (SPFA) with minimal beam pointing error for a centrosymmetric planar array antenna. The theoretical expression of a beam pointing error caused by phase quantification error is derived. On the basis of the derivation results, the phase shift of each element is sequentially quantified through truncating or carrying to achieve a smaller beam pointing error. The proposed algorithm improves the beam pointing accuracy of the centrosymmetric planar array antenna, and the computational load is acceptable. Simulation results verify the effectiveness of SPFA. 相似文献
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MFOA‐integrated modified inverted F‐based adaptive array Antenna for 2.4 GHz band applications 下载免费PDF全文
This research has proposed a modified fruit fly optimization algorithm (MFOA)‐integrated adaptive array antenna (AAA) for the 2.4–2.5 GHz WLAN system. The principal components of the array antenna system encompass four array elements, four band pass filters (BPF), four digital phase shifters, a four‐way power combiner/splitter, a directional coupler, a radio frequency (RF) detector, and a microcontroller unit (MCU). In the realization of the adaptive antenna system, the modified inverted F antenna with a finite ground plane was first innovated and subsequently deployed as the element of the four‐element array antenna. In the study, simulations and experiments were carried out with the four‐element AAAs of two configurations, i.e. the linear and planar array configurations. The simulation and experimental results revealed that the MFOA algorithmic scheme could determine the direction of the maximum arrival signal in an efficient and accurate manner and also was capable of manipulating the radiation pattern in the desired direction. In addition, the MFOA‐integrated four‐element AAA is of compact size (20 mm × 35 mm × 1.8 mm) and operable in the 2.31–2.55 GHz frequency band with omnidirectional radiation pattern and a gain of 1.6 dBi. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2016. 相似文献
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在介绍罗兰C全向磁天线设计方法和接收特性的基础上,针对全向磁天线信号合成中的数字移相环节,设计了一种高精度数字移相算法,该算法突破了传统数字移相算法移相精度受信号采样率限制的缺陷,实现了信号的高精度数字移相。利用罗兰C标准脉冲信号对移相算法进行了仿真计算,并用实际采集的罗兰C信号进行了验证,结果均表明了算法的正确性和优越性。该算法具有计算过程简单,易于采用高性能硬件逻辑可编程芯片FPGA/CPLD来实现,在罗兰C全向磁天线设计中获得了较好的应用效果。 相似文献
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Broadband planar dipole array Antenna with double C‐shaped slit elements for digital TV broadcasting transmission 下载免费PDF全文
This research has proposed a planar rectangular dipole antenna enclosed in double C‐shaped parasitically slit elements (i.e., radiator element) on a double‐cornered reflector for bandwidth enhancement. In the study, simulations were first carried out to determine the optimal parameters of the radiator element and then a radiator element prototype was fabricated and mounted onto a double‐cornered aluminum reflector. The simulated and measured |S11|<–10 dB of the antenna element covered the frequency ranges of 451–901 MHz (66.6%) and 455–886 MHz (64.3%), respectively. The gain was enhanced by the subsequent deployment of multiple radiator elements to fabricate a four‐element vertically array antenna on an elongated double‐cornered reflector. The simulated and measured |S11|10 dB of the array antenna, respectively, covered the 410–991 MHz (82.9%) and 415–886 MHz (72.4%) frequency ranges. The proposed array antenna radiates unidirectionally across the DTV frequency band with a measured front‐to‐back ratio and cross polarization >20 and 23 dB, respectively. The simulated and measured half‐power beam widths in the E and H planes were respectively 56° ± 13° and 20° ± 6°; and 57° ± 13° and 21° ± 6°. In addition, the simulated and measured gains of the array antenna were 12.8–16.4 dBi and 11.3–15.8 dBi along the 470–862 MHz frequency range. This proposed array antenna is thus suitable for DTV broadcasting transmission. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:466–478, 2016. 相似文献
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Mohammad Khalaj‐Amirhosseini 《国际射频与微波计算机辅助工程杂志》2019,29(12)
An approach is presented to synthesize linear and planar antenna arrays to have concurrent multibeam radiation patterns as well as desired sidelobe levels. This approach is based on zeros perturbation of the pattern of linear arrays. Multibeam planar arrays are synthesized by both multiplying and transforming multibeam linear arrays. Besides, planar arrays having conical or ring type beam are synthesized by applying a special transformation to dual‐beam linear arrays. Some examples are brought to verify the effectiveness of the proposed approach for both linear and planar arrays. 相似文献
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The reconfigurable design problem is to find the element that will result in a sector pattern main beam with side lobes. The same excitation amplitudes applied to the array with zero phase should be in a high directivity, low‐side lobe pencil‐shaped main beam. This work presents a multiobjective approach to solve this problem. We consider two design objectives: the minimum value for the dual beam and the dynamic range ratio in qualify the entire array radiation pattern in order to achieve the optimal value between the antenna‐array elements. We use a recently developed and very competitive multiobjective evolutionary algorithm, called MOEA/D. This algorithm uses a decomposition approach to convert the problem of approximation of the Pareto Front into a number of single objective optimization problems. We illustrate that the best solutions obtained by the MOEA/D can outperform stat‐of‐art single objective algorithm: generalized generation‐gap model genetic algorithm (G3‐GA) and differential evolution algorithm (DE). In addition, we compare the results obtained by MOEA/D with those obtained by one of the most widely multiobjective algorithm called NSGA‐II and mutliobjective DE. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE 22: 675–681, 2012. 相似文献
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Balu Ashvanth Bactavatchalame Partibane Mohammed Gulam Nabi Alsath Rajakani Kalidoss 《国际射频与微波计算机辅助工程杂志》2019,29(12)
This article presents the design of a pattern switchable patch antenna for vehicular applications. The proposed antenna has a square patch that is divided into four triangular regions using diagonal rows of vias. The triangular regions are separately excited using a coaxial feed to achieve frequency and pattern reconfiguration. Each triangular section of the antenna has “U” shaped and inner rectangular strips to obtain two resonant frequencies of 2.4 and 3.5 GHz, respectively to cover the part of WLAN, WiMax, and car‐to‐car communication ranging from 3.4 to 3.8 GHz. In order to cover the maximum bandwidth of WLAN and WiMax standards, frequency tuning is done using a varactor diode. Upon exciting any one of the port, the antenna generates a tilted beam with a peak gain of 6.8 and 5.8 dBi at 2.45 and 3.5 GHz, respectively. A full azimuth beam coverage can be achieved by exciting the ports sequentially. The antenna is also capable of generating eight other beams using multiple feed excitations with the maximum gain of 8.4 and 9.4 dBi for the axial beam at 2.45 and 3.5 GHz, respectively. 相似文献