Rectillinear arrays and their combined radiation patterns

A disadvantage of simple antenna is they do not always perform to specified requirements, such as the required width of the main lobe of radiation pattern (RP). In response, we often utilize straight array (SA) containing N emitters; each of which is employed as a simple antenna. The distance ‘d’ and the current phase difference ‘h’ between adjacent emitters are permanent.  Requirements to insure SA are given depending on F (θ) – normalized RP multiplier of SA to the angle θ of spherical coordinate systems.