An Overview on Synthesis Techniques for Near-Field Focused Antennas

Pino, Marcos R.; Ayestaran, R.G.; Nepa, Paolo; Manara, Giuliano

doi:10.5772/intechopen.89600

Cited by 10 publications

(5 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The conjugate phase method is probably the most used approach, as it is also the simplest one, to realize the focusing condition. However, it does not allow to consider the mutual couplings between the antenna elements [43].…”

Section: Problem Formulationmentioning

confidence: 99%

Tolerance Analysis of Near-Field Focused Arrays to Safe-for-Humans Microwave and RF Applications

Buonanno,

Costanzo

2024

IEEE Trans. Antennas Propagat.

View full text Add to dashboard Cite

A methodology is proposed in this work to characterise the complex vector near-field of focused antenna arrays with arbitrary geometry, subject to random errors. Starting with the problem formulation, a proper mathematical relationship for the actual electric field is established, and a partial statistical characterisation is then performed. Subsequently, the mean squared errors are computed between the actual and the desired electric field, and between the actual and the ideal squared magnitude of the electric field. Finally, a method to determine the cumulative distribution function of the squared magnitude of the electric field is discussed for obtaining appropriate percentile functions. The presented numerical results show the validity of the proposed technique, which is particularly useful in those applications, such as the biomedical ones, where high performance is required to control the electric field values such to guarantee human safety conditions.

show abstract

Section: Problem Formulationmentioning

confidence: 99%

Tolerance Analysis of Near-Field Focused Arrays to Safe-for-Humans Microwave and RF Applications

Buonanno,

Costanzo

2024

IEEE Trans. Antennas Propagat.

View full text Add to dashboard Cite

show abstract

“…where we have defined ∆x nm x m − x n and ∆y nm y m −y n . By computing the solution in (8) with the expressions in (23) for A and B, this corresponds to the "maximum BCE" method. Thus the "maximum BCE" method is a special case of 7: Plot of the efficiency η = P S /P inc as a function of the distance z between the surface S and the infinite ground plane below the of dipoles.…”

Section: Maximum Active Power Flow: Far-field Casementioning

confidence: 99%

“…The method is extended to vector fields in [22]. Several other constrained optimization techniques have been proposed to select the excitation of the NF array in [23].…”

Section: Introductionmentioning

confidence: 99%

Synthesis of Near-Field Arrays based on Electromagnetic Inner Products

Lisi¹,

Michel²,

Nepa³

2022

Preprint

View full text Add to dashboard Cite

Near-field antennas have been successfully adopted in several wireless applications. To exploit the high reconfigurability of array antennas, multiple synthesis techniques for arrays operating in the near-field region have been proposed. Building upon previous works on eigenmode expansions of the radiated fields, two synthesis methods for the excitations of nearfield arrays based on the definition of an inner product on the electromagnetic fields are investigated: the "maximum norm" and "minimum error field norm" methods. The "maximum norm" method computes the array excitations that maximize either the active power flow through a target surface or the electric/magnetic energy stored in an assigned volume, depending on the adopted inner product. The performance of the maximum active power flow method is compared with the one of the simpler conjugate phase method. Furthermore, the limit solution achieved when the target surface reaches the far-field region is compared against the "maximum Beam Collection Efficiency" method. The "minimum error field norm" method allows to synthesize a given target field. As an example, the latter method is used to find the optimal excitation of a Plane Wave Generator with a spherical quiet zone. The effectiveness and performance of the discussed synthesis methods are validated through numerical simulations.

show abstract

“…To overcome these drawbacks, the optimal WPT solution would be based on radiative energy transfer, without the mandatory request of a line of sight between transmitter and receiver, and wherein a greater amount of energy is delivered and confined within the spatial location where it is required. In this respect, different approaches have been proposed in the literature [7][8][9][10][11][12][13]. For instance, a unified approach for energy harvesting and wireless power transmission is provided in [13], while experiments for radiative transmissions are provided in [11].…”

Section: Introductionmentioning

confidence: 99%

An Efficient Far-Field Wireless Power Transfer via Field Intensity Shaping Techniques

2021

View full text Add to dashboard Cite

Radiative (or far-field) energy replenishment for devices such as smartphones, laptops, robots, and small electric appliances paves the way to autonomous and continuous devices functioning, thus bypassing the need of operation interruptions, human maintenance activities, and replenishment by wired transformers. In this work, we investigate the feasibility of using a properly engineered antenna array able to deliver radiative power to devices in need of energy replenishment during their normal and unsupervised activity, whose locations are unknown. Both the case of single and multiple devices needing energy replenishment are addressed. A quantitative proof-of-concept study is carried out to validate the proposed approach. A 3D scenario is simulated to study the case of devices in need of energy replenishment within a standard office environment. Different antenna array configurations are investigated and the corresponding performances benchmarked against a standard installation of recharging antennas. Results confirm the outstanding capability of the proposed approach in terms of confinement and maximization of power transfer. Finally, in this framework, we also propose an efficient communication protocol that is able to manage multiple recharge demand given different operational rules.

show abstract

An Overview on Synthesis Techniques for Near-Field Focused Antennas

Cited by 10 publications

References 46 publications

Tolerance Analysis of Near-Field Focused Arrays to Safe-for-Humans Microwave and RF Applications

Tolerance Analysis of Near-Field Focused Arrays to Safe-for-Humans Microwave and RF Applications

Synthesis of Near-Field Arrays based on Electromagnetic Inner Products

An Efficient Far-Field Wireless Power Transfer via Field Intensity Shaping Techniques

Contact Info

Product

Resources

About