Unequally excited generalised random binned antenna arrays

Abstract

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.

Statistically Thinned Array Antennas for Simultaneous Multibeam Applications

“…As can be seen, the side-lobes of |F (u)|/max{|F (u)|} increase with the number of beams. This trend was already observed for random aperiodic arrays [24] [29]. However, the main lobes of the actual and reference array factors are very similar.…”

Global Characterization of Linear Statistically Thinned Antenna Arrays

“…As expected, the P SLL values increase as compared to the previous examples. However, what matters is that our estimation still shows an excellent agreement with the experimental distribution, which is by far much better than (28) and (29). It worth observing that the P SLL prediction through (29) improves when the degree of thinning (16)) and asymmetric (returned by ( 15)) statistically thinned arrays for N = 1000 and for µ s (u) = µ(u) = F REF1 (u) and F REF2 (u).…”

“…level of thinning one may want to adopt. Note that this does not hold true for estimations given by (28) and (29).…”

“…Alternatively, one may be interested in how much the array factor deviates from the reference one. In this circumstance, say LB(u) = µ s (u)−ξ σ s (u) and U B(u) = µ s (u)+ξ σ s (u) the lower and upper barriers within which F s (u) should be confined, then (13) particularizes as [29]…”

Broadband Statistically Designed Thinned-Binned Array Antennas

“…The proposed method preserves the very low computational cost, and it inherits the STAs's ability to reduce the number of elements, as well as the very large bandwidth (without grating lobes) instead characterizing the binned arrays. In addition, unlike totally random arrays [1] [26]- [27], the binning step also imposes some constraints on the radiators positions, so that only the adjacent ones could be close. More in detail, due to the binned step, each radiator is deployed according to a uniform probability density function only within a single bin.…”