The element failure of antenna arrays increases the sidelobe power level. In this paper, the problem of antenna array failure has been addressed using Fire∞y Algorithm (FA) by controlling only the amplitude excitation of array elements. A fltness function has been formulated to obtain the error between pre-failed (original) sidelobe pattern and measured sidelobe pattern and this function has been minimized using FA. Numerical example of large number of element failure correction is presented to show the capability of this ∞exible approach.

A linear antenna array failure correction using firefly algorithm

Switched-beam dipole arrays (SBAs) are widely used in order to increase system performance in wireless communications. They represent an attractive alternative to fully adaptive arrays, due to lower deployment and maintenance costs. Dual-band operation and elements failure correction are dealt with in this paper, since they are considered to be key characteristics in modern systems, like WiFi/WiMAX, and remote base stations maintenance respectively. The focus of the presented work is on the preservation of constant excitation coefficients during dual-band operation (coefficients will change after a possible elements failure), but the possibility of retaining universal, constant excitations, even after element failures, is also examined (the term universal means that excitations are kept constant, regardless of element failure or frequency of operation). This is accomplished using a genetic algorithm (GA), and numerical results are presented which demonstrate the eligibility of the proposed technique.

Genetic Design of Dual-band, Switched-beam Dipole Arrays, with Elements Failure Correction, Retaining Constant Excitation Coefficients

The failure of antenna array elements causes disturbance in the sidelobe power level. In this article, an improved flexible approach that use bat algorithm is proposed and applied to solve the problem of antenna array failure by controlling only the amplitude excitation of array elements. An adaptive inertia weight approach is applied to the standard bat algorithm to improve the quality of the solution and the speed of convergence. The effectiveness of the proposed improved bat algorithm (IBA) is verified on different standard test functions. Numerical examples of element failure correction are presented to show the capability of this flexible approach in antenna array failure correction.

A linear antenna array failure correction using improved bat algorithm

The element failure of digital beam forming array antenna systems used in defence equipment increases the side lobe power level which distorts the beam pattern of the antenna array. The problem of array failure correction becomes more complex when null steering conditions are required to be added. In this paper, the problem of linear antenna array failure has been addressed with multiple wide band null steering using firefly algorithm (FA) by controlling the amplitude and phase excitation of array elements. A fitness function in the form of template has been formulated to obtain the error between original (pre-failed) side lobe pattern and measured side lobe pattern and this error function has been minimized using FA. Numerical example of element failure correction of element failure of array along with multiple nulls is presented to show the capability of this flexible approach. Defence Science Journal, 2014, 64(2), pp. 136-142.  DOI: http://dx.doi.org/10.14429/dsj.64.4250

A Linear Antenna Array Failure Correction with Null Steering using Firefly Algorithm

The element failure of antenna arrays disturbs the sidelobe power level In this paper, the problem of circular antenna array failure is mitigated using firefly algorithm (FA) by controlling the amplitude excitation of array elements A fitness model has been developed to obtain the error between pre-failed (original) sidelobe power pattern and measured sidelobe power pattern and this function has been minimized using FA Numerical examples of different circular array structures with element failure correction are presented to show the capability of the proposed approach

A Non-Uniform Circular Antenna Array Failure Correction Using Firefly Algorithm

The orthogonal method is used to improve the patterns of the linear array in the presence of failed elements. Reconfiguration of the amplitude and phase distributions of the remaining elements can partially compensate for the failed elements and thus reduce the sidelobe level. Numerical results are presented to illustrate the effectiveness of the method. The effect of the number of failed elements, the distance between the elements and the shape of the desired pattern is demonstrated through this paper.

http://ieeexplore.ieee.org/iel5/9234/29272/01321774.pdf

M.S. Ibrahem

Papers

Array failure correction with orthogonal method