# Reduction of Phase Shifters in Planar Phased Arrays Using Novel Random Subarray Techniques
## 2 Random Subarray Design Methodology
### Fusions of Subarrays
The scanning range in the elevation plane is illustrated by the red rectangle (\(-40^{\circ}\leq\theta\leq 0^{\circ}\)) with an azimuth scanning range of \([-75^{\circ}\leq\phi\leq 75^{\circ}]\). The color palette for different radiation patterns indicates each step angle \(\Delta\phi\) shown in Table 4.

To overcome this, computational intelligence in the form of evolutionary algorithms was applied to the search of solutions that satisfy diverse instances of the phased array design problem by partially exploring massive spaces of solutions [14; 19; 20; 21]. The designs mentioned in Sections 3.3 and 3.4 illustrate the various applications of the planar phased arrays, given a set of design variables that are generally defined by the main task of the application, such as tracking the orbit of a satellite given a desired scan range [22] or an automotive application [13]. This diversity of solutions is shown in Table 5, with the comparison of Case IV of this work with other cases. The methodology presented in this work showed great flexibility in searching for new phased antenna array designs that met the requirements of an specific application in a short period of time. Conceptualization, C.A.B. ; Methodology, J.L.V. and M.A.P. ; Software, J.L.V. ; Validation, J.L.V. and C.d.R.B. ; Formal analysis, J.L.V. and D.H.C. ; Investigation, J.L.V. and M.A.P. ; Resources, M.A.P. and C.d.R.B. ; Writing - original draft, C.A.B. and J.L.V. ; Writing - review & editing, C.d.R.B. and C.A.B. ; Supervision, M.A.P. ; Project administration, D.H.C. ; Funding acquisition, D.H.C. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Not applicable. The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results. ## References

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