The antenna array is optimized at 698 mhz center frequency of dvbt channel 49 to concurrently achieve a particular radiation pattern shaping with high forward gain, main lobe tilting and null filling inside the service area, as well as low sidelobe level outside the service area, and low standing wave ratio at the inputs of all the array. Array sidelobes, error tolerance, gain, and beamwidth dtic. Examples are given to validate the presented method for the two array types. The main drawback of this antenna is high side lobe level and grating lobe at different. Offer flexibility over single antenna elements array factor element factor direct synthesis methods for designing af. Apart of producing narrow beam antenna low sidelobe level is also needed to.
Pdf side lobe level reduction in antenna array using weighting. For uniformlyspaced arrays, the design methods are identical to the methods for designing fir digital. Pdf synthesis of a linear antenna array for maximum sidelobe. Sidelobe level reduction in microstrip patch antenna array. Balanis, antenna theory analysis and design, a john wiley and. Peak sidelobe level distribution computation for ad hoc arrays using extreme value theory the harvard community has made this article openly available. Raoprithvi 2 department of ece, raghu institute of technology, visakhapatnam, india. This is achieved at the expense of a slight increase in main lobe beamwidth i. Then, the formulated problem is solved by using the invasive weed optimization iwo algorithm. By this method, arrays have the ability to produce the desired radiation pattern and could satisfy requirements for many applications.
The farfield region is the most important field, as this determines the antennas. Optimizing the sidelobe level of a twoway antenna array. In fact, historically, these methods were first developed in antenna theory and only later were. Antennas and propagation slide 18 chapter 4 symmetric array. This technique proved its effectiveness in improving the performance of the antenna array. Sidelobe suppression in a corporatefeed doublelayer. Printed antenna arrays with high side lobe suppression. In a modern radar system, the peak sidelobe level, however, is more important. Beam pattern characteristic is one of the most important properties of an antenna array 6. Many conventional numerical techniques are proposed to achieve this which are time consuming and often fail to handle multimodal problems.
Phased array antenna can produce beam with high directivity at any direction without any physical movement of the antenna array. Gap coupled array concept is proposed for low radiation coefficient. Linear antenna array with suppressed sidelobe and sideband. A pareto elite selection genetic algorithm for random antenna array beamforming with low sidelobe level suhanya jayaprakasam, sharul k.
In a linear antenna array, antenna elements are placed along one axis. The farfield region is sometimes referred as fraunhofer region, a carryover term from optics. Sidelobe level is an important metric used in antenna arrays, and depends on the weights and positions in the array. Abstractin most applications of antenna arrays, side lobe levels slls. Sidelobe reduction of unequally spaced arrays for 5g. Introduction adaptive beamforming is a signal processing technique in which.
Antenna arrays page 1 antenna arrays recall from our previous discussion of the 2element array that the total eld pattern from an array could be found by multiplying the element factor the pattern produced by a single element by. In antenna engineering, side lobes or sidelobes are the lobes local maxima of the far field radiation pattern of an antenna or other radiation source, that are not the main lobe the radiation pattern of most antennas shows a pattern of lobes at various angles, directions where the radiated signal strength reaches a maximum, separated by nulls, angles at which the radiated signal. Analysis of linear antenna array for minimum side lobe. Array antenna, which is a system of similar antenna elements oriented similarly to.
Synthesis of a linear antenna array for maximum sidelobe level reduction s. The low sidelobe level is obtained by implementing the chebyshev polynomial to distribute the power to each element of the patch. Research article synthesis of circular array antenna for. Design of controlled feed by nonuniform excitation, for linear array is mentioned to. Design of low side lobe level milimeterwave microstrip. Index termslinear antenna array, improved directivity, null control, particle swarm optimization, minimum side lobe level, half power beamwidth. Yagiuda antenna use a driven element a dipole or a folded dipole, and one or more parasitic elements, as reflectors and directors.
Using the differential evolution algorithm dea, low sidelobe level sll seriesfed microstrip antenna arrays of unequal interelement spacing ies are investigated. Synthesis of linear antenna array using genetic algorithm. A method of determining optimal sidelobe minimizing weights is derived that holds for any linear array geometry, beamwidth, antenna type and scan angle. Pdf phased array antennas are generally used for the inherent flexibility to steer the beam electronically and also the need for specialized. Thus, synthesizing the beam pattern of an antenna array is very. Introduction an antenna array is a combination of two or more antenna elements that can be placed in a specific geometry. Pattern sidelobe level suppression on antenna array with arbitrary geometry by the irls algorithm conference paper pdf available february 2001 with 103 reads how we measure reads. An antenna array sidelobe level reduction approach through. Optimization of sidelobe level of thinned phased array antenna using genetic algorithm and particle swarm optimization abstract. Your story matters citation krishnamurthy, siddhartha. Operation requirements are usually specified in terms of peak. First, an optimization problem is formulated for reducing the maximum sidelobe level sll of the beam patterns.
Abstractin this paper, a high performance phased antenna array is designed. Pdf pattern sidelobe level suppression on antenna array. The approach followed here is not to give fixed level of excitation to the elements of an array, but to change it dynamically with time. A sidelobe level reduction sll for planar array antennas. Influence of several factors that make difficult design and realization of antenna arrays with relatively high sls has been analyzed. From antenna theory, we know that the excitation distribution and. Thus the reflectivity levels that stretch southward from the reflectivity maximum can be echoes received through antenna sidelobes i. Wideband dualpolarized twobeam antenna array with low. A method of determining optimal sidelobeminimizing weights is derived that holds for any linear array geometry, beamwidth, antenna type and scan angle. Keywords adaptive beamforming, sidelobe level, genetic algorithm, linear antenna array, pattern synthesis, convergence, array factor.
Maximum sspar array sidelobe level as a function of number of antenna channels. We introduced a new type of printed antenna array with symmetrical pentagonal dipoles and symmetrical tapered feed network with chebyshev distribution. In this section we discuss array design methods and consider various design issues, such as the tradeoff between beamwidth and sidelobe level. Antennas and propagation slide 2 chapter 4 5 antenna arrays advantage. In 5, the concept of circular, triangular and pieshaped slots is proposed to decrease the sidelobe and to increase the gain. A directional mainlobe with the low sidelobe level sll of the beam pattern will e. The excitation levels of the different array elements over time are varied to get the low sidelobe and sideband levels. Sidelobe level reduction in linear array pattern synthesis. Pdf synthesis of circular array antenna for sidelobe.
Sidelobe level suppression is a major problem in circular array antenna caa synthesis. A novel technique for sidelobe and backlobe reduction in. Peak sidelobe level distribution computation for ad hoc arrays using extreme value theory. Peak sidelobe level distribution computation for ad hoc. Synthesis of a linear antenna array for maximum sidelobe. The designed antenna which has low sidelobe level is designed using the concept of taylor pattern synthesis and genetic algorithm.
The present antenna array permit thinning factors well below onehalf while retaining the sidelobe level characteristics of arrays with much higher. Pdf sidelobe level reduction in microstrip patch antenna. The proposed design method can achieve conversion between the sll and halfpower. The present invention relates to thinned linear, planar and threedimensional phased antenna array configurations which have the antenna or sensor elements positioned in a pseudorandom manner as prescribed by the equation based on difference sets. This paper optimizes the array elements weights with. Reduction of sidelobes by nonuniform elements spacing of a. Ideal array performance is obtained from classical array theory n e. Leow wireless communication centre wcc, faculty of electrical engineering, universiti teknologi malaysia, utm skudai 810, malaysia abstractrandom antenna array raa that uses the. Introduction in addition to the linear antenna array con. Development of low sidelobe level array antenna for.
This work proposes a tunable sidelobe reduction method based on a gan activeantenna technique, in which the output radio frequency power is controlled by the dc drain voltage of the amplifiers. In this paper, a linear series fed yagilike antenna array is introduced leading to an endfire fan beam with low sidelobe level, sll, high front to back ratio, fb, and wide impedance bandwidth. Babale and others published synthesis of a linear antenna array for maximum sidelobe level reduction find, read and cite all. The problems of synthesizing the beam patterns of the linear antenna array laa and the circular antenna array caa are addressed. This antenna can provide high gain in a particular direction from the driven element to. The results compared with those of the application of gaussian, kaiser, hamming, blackman and chebyshev weight coefficients produce a significant improvement for the array peak sidelobe level psl. Analysis of linear antenna array for minimum side lobe level, half. The taylor nbar distribution achieves an optimal tradeoff between gain and sll. Rectangular and circular arrays with independently.
For five elements square array antenna, the simulated axial ratio bandwidth sidelobe level. The most commonly used method for reducing the sidelobe levels of a uniform array involves amplitude tapering,in which the excitation amplitudes of the array elements generally decrease with the distance from the center of the array. Sidelobe reduction with a gan active array antenna. Mandal, nulls and sidelobe levels control in a time modulated linear antenna array by optimizing excitations and element locations using rga, journal of microwaves, optoelectronics, and electromagnetic applications, vol. Optimization of sidelobe level of thinned phased array. Optimal design of aperiodic reconfigurable antenna array. As a function of the number of antenna elements, figure 33 shows the maximum array sidelobe level for a 4 m diameter, sparse, circular array designed using numerical optimization approaches to minimize sidelobes. The positions are then optimized simultaneously with the. The first sidelobe level is fully suppressed at about 24db. Keywords wireless communications nonuniform array antenna sidelobe level reduction particle swarm. The problem of side lobe suppression sls in printed antenna arrays has been investigated in the paper. Keywords radiation pattern, spherical array, sidelobe level reduction, uniform and nonuniform distribution of antenna. Research article synthesis of circular array antenna for sidelobe level and aperture size control using flower pollination algorithm v. Antenna array pattern by thinning the receive aperture randy l.
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