Generalised Random Binned Antenna Arrays

IET Microwaves, Antennas & Propagation

2019

Self Cite

It has been recently shown that random arrays paired with a proper excitation strategy can be used to shape the array factor. These random arrays were termed unequally excited totally random arrays (TRAs). This scheme allows to greatly enlarge the class of obtainable patterns, well beyond the classical single beam. However, its main disadvantage is a reduction of the achievable performance, the latter measured in terms of the deviation from the average array factor. In this contribution, a strategy for remedying (even only partially) to such a loss of performance by retaining the same flexibility in shaping the pattern is addressed. To this end, a new scheme for generating random arrays that merges unequal excitations and a suitable generalised binned procedure is introduced. It is shown that this new model of generalised binned arrays always outperforms unequally excited TRAs. In particular, the study is focused on symmetric arrays (for which the elements are deployed symmetrically with respect to the array aperture centre) which allows to get closed‐form expressions without invoking some common assumptions that in general do not hold true in practice. The theoretical findings are assessed by several numerical examples for the case of multi‐beam array factors.

“…Before introducing the new random generation scheme, in order to keep the paper self-contained, it is necessary to dwell on the theory of GBAs that has been recently introduced in [29].…”

Section: Generalised Binned Arraysmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Unequally excited generalised random binned antenna arrays

Buonanno¹,

IET Microwaves, Antennas & Propagation

2019

Self Cite

“…In order to get a more complete characterisation we employ the uniform norm distribution of | (u)|, that is [6] P ε = max…”

Section: Design Error Estimationmentioning

confidence: 99%

“…The study is organised as in [6], considering only symmetric arrays. This is because the math is much easier, and after all there is no significant degradation in terms of the achievable performance with respect to the asymmetric case [7].…”

Section: Introductionmentioning

confidence: 99%

Study of Unequally-Excited Random Antenna Arrays for Beam Shaping

Buonanno¹,

2018

PIER C

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Abstract-Random arrays have been typically studied by considering real uniform excitations. This is suited for single-beam radiation patterns but does not allow for more sophisticated patterns. Indeed, only even patterns, with respect to the steering angle, can be achieved. To overcome this limitation, we recently proposed a new model whereby the excitation coefficients are not uniform and are determined by means of two random variable transformations. In this paper, we deal more extensively with the properties of this model, highlighting things that have not been pointed out previously. In order to get analytical results, we just consider symmetric random arrays. For such a case, we determine the design error, that is the cumulative distribution function of the supremum of the the difference between the actual and desired array factors. It is shown that general shaped beams can be actually achieved but at the cost of an increase of the design error as compared to the single-beam case. Numerical analysis validates the presented theory.

Unequally‐excited linear totally random antenna arrays for multi‐beam patterns

Buonanno¹,

IET Microwaves, Antennas & Propagation

2018

Self Cite

Linear random antenna arrays are usually studied in conjunction with uniform excitations with, at most, a linear phase shift in order to steer the main beam. This offers some advantages in terms of the feeding network but puts limitations on the array factor that can be obtained. The authors introduce unequally excited random arrays whose excitation currents are obtained by suitable transformations of the random variables related to the element positions. Besides, the first‐ and second‐order statistic characterisation, the uniform norm (i.e. the supremum) of difference between the mean (the desired one) and the actual array factors is estimated. In particular, while in the general case, this is achieved only via a Monte Carlo study, for the case of symmetric arrays (where the elements are randomly deployed symmetrically with respect to the array aperture centre) that norm is analytically estimated using the up‐crossing theory for random processes. It is shown that the proposed unequally excited random arrays, unlike some other previous approaches, allow shaping the mean radiation pattern. However, the procedure in general yields reduced achievable performance. Therefore, the theoretical findings are checked through some numerical examples only for the important class of multi‐beam array factors.