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Adaptive Antenna Arrays

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Adaptive antenna arrays are advanced antenna systems that dynamically adjust their radiation patterns and beamforming capabilities in response to changing signal environments. This technology enhances signal reception and transmission by optimizing the spatial characteristics of the antenna array, improving performance in applications such as wireless communications and radar systems.
lightbulbAbout this topic
Adaptive antenna arrays are advanced antenna systems that dynamically adjust their radiation patterns and beamforming capabilities in response to changing signal environments. This technology enhances signal reception and transmission by optimizing the spatial characteristics of the antenna array, improving performance in applications such as wireless communications and radar systems.

Key research themes

1. How do adaptive beamforming algorithms compare in performance and convergence for optimizing smart antenna arrays in dynamic wireless environments?

This research area focuses on the development and evaluation of adaptive beamforming algorithms such as LMS (Least Mean Squares), CMA (Constant Modulus Algorithm), RLS (Recursive Least Squares), CGM (Conjugate Gradient Method), and hybrid genetic/meta-heuristic algorithms. The goal is to optimize beam steering in smart antenna arrays to maximize signal-to-interference-plus-noise ratio (SINR), minimize sidelobe levels, and enhance system capacity in varying interference and fading channel conditions. Understanding the trade-offs between convergence speed, computational complexity, and robustness is vital for real-time practical deployment in wireless communications.

Key finding: This study provides a comparative analysis of adaptive beamforming algorithms, demonstrating that while LMS offers low computational complexity and stability, it exhibits slower convergence compared to RLS. CMA, a blind... Read more
Key finding: This paper applies hybrid genetic and meta-heuristic algorithms to optimize weights and antenna element spacing in linear arrays, outperforming classical adaptive beamforming techniques such as LMS and RLS regarding... Read more
Key finding: Incorporating variable inter-element spacing alongside adaptive weight updating with the LMS algorithm yields superior sidelobe reduction and minimized mean square error compared to uniformly spaced arrays. This adjustment to... Read more
Key finding: This paper reveals that adaptive nulling is highly sensitive to random amplitude and phase errors in element excitations. Using constrained optimization to design the weights, the study shows that sidelobe levels increase and... Read more

2. What design methodologies and antenna configurations optimize wide-angle scanning and multi-beam formation in adaptive antenna arrays while managing hardware complexity and losses?

This theme addresses antenna array structural designs and analog feeding network architectures, including innovative array geometries (e.g., faceted arrays, uniform circular arrays) and beamforming networks such as Blass matrices. The research tackles the trade-offs inherent in achieving wide scanning ranges, multi-beam capability, reduced sidelobe levels, and efficient power utilization against the complexity, losses, and practical manufacturing constraints in large-scale antenna array deployments for next-generation wireless systems.

Key finding: Proposes a 3-faceted array geometry achieving a wide angular scan range up to ±70°, surpassing the ±56° of traditional uniform linear arrays. The study integrates phase correction and amplitude tapering to reduce sidelobe... Read more
Key finding: Introduces an efficient iterative design of Blass matrix beamforming networks using identical directional couplers, enabling flexible multi-beam synthesis for arbitrary linear arrays. The approach simplifies hardware... Read more
Key finding: Demonstrates that uniform circular array configurations synthesized via Cuckoo Search Algorithm can achieve better beamforming characteristics, including lower sidelobe levels and consistent beam width during scanning,... Read more
Key finding: Examines electronically steerable parasitic array radiator (Espar) antennas, which use a single active feed and electromagnetic mutual coupling for beamforming. It develops algorithms for omnidirectional, sector, and blind... Read more

3. How can frequency diverse arrays (FDA) be jointly designed in the space-frequency domain to achieve stable and controllable scanning beam patterns for radar and communication applications?

Frequency Diverse Arrays introduce frequency offsets across elements to create range-angle dependent time-variant beam patterns with auto-scanning capabilities. Research in this theme concentrates on adjoint space-frequency design algorithms that simultaneously optimize element spatial locations and frequency distributions to ensure predictable beam periodicity, stable sidelobe levels, and desired scan rates. Achieving this enables FDAs to overcome fluctuations in beam patterns, making them viable for practical scanning applications in radar and wireless communications.

Key finding: Presents a novel adjoint spatial-frequency algorithm that simultaneously optimizes element frequency and spatial distributions using a symmetrical FDA array factor formulation. The algorithm enforces unified scan periodicity... Read more
Key finding: Extends FDA design by deriving a simplified analytical expression for the array factor based on spatial symmetry, enabling calculation of scan periodicity and angle-changing rates for individual array factor exponents.... Read more

All papers in Adaptive Antenna Arrays

Redundant robotic manipulators offer enhanced flexibility, dexterity, and fault tolerance compared to conventional robotic systems. However, this redundancy also introduces significant complexity in motion planning and obstacle avoidance,... more
Los textos e imágenes publicados en esta obra están sujetos -excepto que se indique lo contrario-a una licencia de Reconocimiento-NoComercial-SinObraDerivada (BY-NC-ND) v.3.0 España de Creative Commons. Podéis copiarlos, distribuirlos y... more
Los textos e imágenes publicados en esta obra están sujetos -excepto que se indique lo contrario-a una licencia de Reconocimiento-NoComercial-SinObraDerivada (BY-NC-ND) v.3.0 España de Creative Commons. Podéis copiarlos, distribuirlos y... more
The LPDA antennas are employed widely, especially in the VHF and UHF bands. They have a lower gain, and may be increased by combining several antennas in an array. The arrays are characterized by the location of the elements with respects... more
of the thesis presented by Juan Carlos Gonzalez Islas as a partial requirement to obtain the MASTER OF SCIENCE degree in ELECTRONICS AND TELECOMMUNICATIONS with orientation in TELECOMMUNICATIONS. Ensenada, Baja California, México, August... more
The smart antenna is a new technology and has been applied to the mobile communication system such as GSM and CDMA. Advent of powerful, low-cost, digital processing components and the development of software-based techniques has made... more
The genetic algorithm has proven useful in the design of conventional, static beamforming networks. It is also quite useful as an adaptive algorithm for smart antennas. This paper demonstrates two uses of the genetic algorithm to... more
Water is one of the vital resources for human life. The dramatic change in climate and increase in the population made water insufficient compared to demand. Smart water management is a system that collects meaningful and usable data... more
Wireless link layer multicast is an important service primitive for emerging applications, such as live video, streaming audio, and other content telecasts. The broadcast nature of the wireless channel is amenable to multicast because a... more
Este artículo propone un nuevo esquema de filtro híbrido adaptativo en cascada basado en los algoritmos de mínimos cuadrados promediados y recursivo de mínimos cuadrados para arreglos lineales uniformes de antenas para generar lóbulos de... more
Представлений метод прямого обчислення оберненої кореляційної матриці перешкоди для рішення рівняння Вінера-Хопфа в адаптивних антенних решітках і формуванні "нуля" діаграми спрямованості при усуненні перешкод навігаційних... more
Purpose: On the basis of spatial filtering, we propose a method for direct calculation of the inverse correlation interference matrix with unknown parameters of the input action for controlling the pattern of the adaptive antenna array... more
Smart antennas are becoming popular in the area of cellular wireless communication for capacity enhancement and reduction of the multipath effect and interference. The demand for smart antennas is widely increasing as 5G cellular... more
One of the key parameters in the processing system of a smart antenna system is the direction of arrival of the signal of interest (DOA). DOA's estimation traditionally performed spectral analysis on the signal received by the antenna... more
To effectively detect the targets in any direction, the radar antenna should be in the form of a planar array that has a large number of elements. In such a case, partially adaptive planar arrays, where only a few elements are adaptive,... more
This article is devoted to showing the applications of innovative reconfigurable antenna systems suitableforthenextgeneration4G/5Gdevices.Microwaveantennatechnologycanbeveryuseful for next generation devices based on 4G/5G standards. Next... more
Recent studies and research have centred on new solutions in different elements and stages to the increasing energy and data rate demands for the fifth generation and beyond (B5G). Based on a new-efficient digital beamforming approach for... more