Planar: Broadside directivity and excitation

This synthesis algorithm will design a planar array for a specified directivity or beamwidth and excitation taper. The excitation taper is used to control the side-lobe level and distribution. The array is always designed so that the elements are arranged in the x-y plane, centered on the z-axis, resulting in a bi-directional beam along the positive and negative z-axis.

An example of a 3D pattern for this array.

When this design algorithm is used, the inter element spacing is always 0.5 λ, with an equal number of radiators in the x- and y-direction when gain is specified, and an unequal number of radiators in the x- and y-direction when different 3dB beamwidths are specified in the x- and y-planes. The excitation per element is the product of two linear array excitations, one laid out along the x-axis and the other laid out along the y-axis.

The excitation taper may be set to equal excitation [Uniform], all side-lobes equal [Dolph-Chebyshev or first few side-lobes equal [Villeneuve]. The side-lobe level and number of side lobes (where applicable) can then be set.

More information about how the array synthesis tool should be used can be found in the array article in the information browser. This article also describes the different excitation tapers in more detail, and provides references for further research.