scholarly journals An Efficient Adaptive and Steep-Convergent Sidelobes Simultaneous Reduction Algorithm for Massive Linear Arrays

Electronics ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 170
Author(s):  
Yasser Albagory ◽  
Fahad Alraddady
Keyword(s):  
Antenna Arrays ◽  
Reduction Process ◽  
Damping Factor ◽  
Reduction Algorithm ◽  
Sidelobe Level ◽  
Simultaneous Reduction ◽  
Linear Arrays ◽  
Power Pattern ◽  
Wireless Communications Systems ◽  
Linear Antenna Arrays

Antenna arrays have become an essential part of most wireless communications systems. In this paper, the unwanted sidelobes in the symmetric linear array power pattern are reduced efficiently by utilizing a faster simultaneous sidelobes processing algorithm, which generates nulling sub-beams that are adapted to control and maintain steep convergence toward lower sidelobe levels. The proposed algorithm is performed using adaptive damping and heuristic factors which result in learning curve perturbations during the first few loops of the reduction process and is followed by a very steep convergence profile towards deep sidelobe levels. The numerical results show that, using the proposed adaptive sidelobes simultaneous reduction algorithm, a maximum sidelobe level of −50 dB can be achieved after only 10 iteration loops (especially for very large antenna arrays formed by 256 elements, wherein the processing time is reduced to approximately 25% of that required by the conventional fixed damping factor case). On the other hand, the generated array weights can be applied to practical linear antenna arrays under mutual coupling effects, which have shown very similar results to the radiation pattern of the isotropic antenna elements with very deep sidelobe levels and the same beamwidth.

Influence of the Aperture Edge Diffraction Effects on the Mutual Coupling Compensation Technique in Small Planar Antenna Arrays

2011 ◽  
Vol 57 (1) ◽  
pp. 115-120 ◽  
Author(s):  
Mariusz Zamłyński ◽  
Piotr Słobodzian
Keyword(s):  
Antenna Arrays ◽  
Mutual Coupling ◽  
Planar Antenna ◽  
Sidelobe Level ◽  
Edge Diffraction ◽  
Narrow Angle ◽  
Compensation Technique ◽  
Diffraction Effects ◽  
Linear Antenna Arrays

Influence of the Aperture Edge Diffraction Effects on the Mutual Coupling Compensation Technique in Small Planar Antenna Arrays In this paper the quality of a technique to compensate for mutual coupling (and other phenomena) in small linear antenna arrays is investigated. The technique consists in calculation of a coupling matrix, which is than used to determine corrected antenna array excitation coefficients. Although the technique is known for more than 20 years, there is still very little information about how different phenomena existing in a real antenna arrays influence its performance. In this paper two models of antenna arrays are used. In the first model the effect of mutual coupling is separated from the aperture edge diffraction. In the second model antenna both mutual coupling and aperture edge diffraction effects are included. It is shown that mutual coupling itself can be compensated very well and an ultralow sidelobe level (i.e. -50 dB) could be achieved in practice. In the presence of diffraction effects -46.3 dB sidelobe level has been attained, but radiation pattern can be controled only in narrow angle range (i.e. up to ±60°).

scholarly journals Improved ESPRIT Method for Joint Direction-of-Arrival and Frequency Estimation Using Multiple-Delay Output

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Wang Xudong ◽  
Xiaofei Zhang ◽  
Jianfeng Li ◽  
Jinchao Bai
Keyword(s):  
Antenna Arrays ◽  
Frequency Estimation ◽  
Direction Of Arrival ◽  
Joint Angles ◽  
Linear Arrays ◽  
Estimation Performance ◽  
Multiple Delay ◽  
Joint Direction ◽  
Esprit Algorithm ◽  
Linear Antenna Arrays

An automatic pairing joint direction-of-arrival (DOA) and frequency estimation is presented to overcome the unsatisfactory performances of estimation of signal parameter via rotational invariance techniques- (ESPRIT-) like algorithm of Wang (2010), which requires an additional pairing. By using multiple-delay output of a uniform linear antenna arrays (ULA), the proposed algorithm can estimate joint angles and frequencies with an improved ESPRIT. Compared with Wang’s ESPRIT algorithm, the angle estimation performance of the proposed algorithm is greatly improved. The frequency estimation performance of the proposed algorithm is same with that of Wang’s ESPRIT algorithm. Furthermore, the proposed algorithm can obtain automatic pairing DOA and frequency parameters, and it has a comparative computational complexity in contrast to Wang’s ESPRIT algorithm. By the way, this proposed algorithm can also work well for nonuniform linear arrays. The useful behavior of this proposed algorithm is verified by simulations.

scholarly journals Optimized Hyper Beamforming of Linear Antenna Arrays Using Collective Animal Behaviour

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Gopi Ram ◽  
Durbadal Mandal ◽  
Rajib Kar ◽  
Sakti Prasad Ghoshal
Keyword(s):  
Antenna Arrays ◽  
Optimization Technique ◽  
Optimal Solution ◽  
Beam Width ◽  
Animal Behaviour ◽  
Linear Antenna ◽  
Sidelobe Level ◽  
Real Coded Genetic Algorithm ◽  
Linear Antenna Arrays ◽  
Collective Animal Behaviour

A novel optimization technique which is developed on mimicking the collective animal behaviour (CAB) is applied for the optimal design of hyper beamforming of linear antenna arrays. Hyper beamforming is based on sum and difference beam patterns of the array, each raised to the power of a hyperbeam exponent parameter. The optimized hyperbeam is achieved by optimization of current excitation weights and uniform interelement spacing. As compared to conventional hyper beamforming of linear antenna array, real coded genetic algorithm (RGA), particle swarm optimization (PSO), and differential evolution (DE) applied to the hyper beam of the same array can achieve reduction in sidelobe level (SLL) and same or less first null beam width (FNBW), keeping the same value of hyperbeam exponent. Again, further reductions of sidelobe level (SLL) and first null beam width (FNBW) have been achieved by the proposed collective animal behaviour (CAB) algorithm. CAB finds near global optimal solution unlike RGA, PSO, and DE in the present problem. The above comparative optimization is illustrated through 10-, 14-, and 20-element linear antenna arrays to establish the optimization efficacy of CAB.

scholarly journals A Feeding Network with Chebyshev Distribution for Designing Low Side-lobe Level Antenna Arrays

2017 ◽  
Author(s):  
Toan The Tang ◽  
Tran Minh Nguyen ◽  
Giang Truong Vu Bang
Keyword(s):  
Antenna Arrays ◽  
Linear Array ◽  
Side Lobe ◽  
Power Divider ◽  
Side Lobe Level ◽  
Linear Antenna ◽  
Sidelobe Level ◽  
Weighting Method ◽  
Low Sidelobe ◽  
Linear Antenna Arrays

This paper proposes a feeding networking to gain low sidelobe levels for microstrip linear antenna arrays. The procedure to design a feeding network using Chebyshev weighting method will be proposed and presented. As a demonstration, a feeding network for 8×1 elements linear array with Chebyshev distribution weights (preset sidelobe level of -25 dB) has been designed. An unequal T-junction power divider has been applied in designing the feeding network to guarantee the output powers the same as Chebyshev weights. The obtained results of the amplitudes at each output port have been validated with theory data. The phases of output signals are almost equal at all ports. The proposed feeding network, therefore, can be a good candidate for constructing a low sidelobe level linear array antenna.

MULTI-OBJECTIVES ADAPTIVE ARRAY SYNTHESIS USING SPEEDY-PARTICLE SWARM METHOD

2015 ◽  
Vol 77 (10) ◽  
Author(s):  
N.N.N.A. Malik ◽  
M. Esa ◽  
S.K.S. Yusof ◽  
N.M.A. Latiff
Keyword(s):  
Antenna Arrays ◽  
Particle Swarm ◽  
Main Beam ◽  
Adaptive Array ◽  
Sidelobe Level ◽  
Pattern Synthesis ◽  
Swarm Optimization ◽  
Particle Swarm Method ◽  
Distance Position ◽  
Linear Antenna Arrays

A method of computing the optimum element distance position of multi-objectives adaptive linear antenna arrays (MLAA) is developed by taking several objectives (eg. adaptive capability, beamwidth and minimum sidelobe level (SLL)) into consideration. In this paper, the recently invented algorithm, known as Speedy-Particle Swarm Optimization (SpPSO) algorithm is adopted to optimize the distance between the MLAA elements. Different numerical examples of 8- and 12-element MLAA are presented to validate and illustrate the capability of SpPSO for pattern synthesis with a prescribed adaptive angle, controllable beamwidth and minimum SLL. It was found that by employing SpPSO method, the results provide considerable improvement over the conventional array. It is observed that the maximum normalized SLL of -12.27 dB has been achieved by using SpPSO for 8-element MLAA. The proposed SpPSO-based LAA also able to achieve a beampattern with sufficiently low sidelobes for 12-element MLAA by having maximum SLL of -16.46 dB, a desired wider FNBW of 50° and main beam that is pointing to 20°.  

Sign in / Sign up

Export Citation Format

Share Document