Effect of Array Element Arrangement on Planar Endfire Array Characteristics

Planar end-fire phased array antennas are preferred for their low profile and directional radiation with wide scanning angles. The arrangement of the elements significantly influences their performance. In this paper, the array factors for a planar array consisting of 50 antenna elements based on several different element arrangements are calculated, and the effects of arrangements on the array's characteristics are analyzed. It is observed that compared to the square arrangement, optimized isosceles triangular, equilateral triangular, and rectangular arrangements have relatively lower sidelobe levels for the same aperture size. When the maximum sidelobe levels are the same, these arrangements exhibit a lower half-power beamwidth (HPBW) and larger element spacing, leading to better directivity and reduced coupling between elements. Consequently, flexibly selecting the element arrangement based on specific requirements can achieve optimal performance.