Optimizing Phased Array Beam Shape

A technique to optimize the beam shape of a Phased Array that is not rectangular in shape is presented. Phased Arrays use amplitude weighting (aka windowing) to control the level of the sidelobes. Typically, this weighting results in the elements at the vicinity of the corners of a rectangular array to be heavily attenuated. As a result, the corner elements have negligible contribution to the EIRP (effective isotropic radiated power) when the rectangular array is used for transmitting. For the receive case being mindful of the impact of removing the corner elements and their effect on the sidelobe levels is needed but many applications can take advantage of removing these elements. Consequently, removing these corner elements helps reduce cost especially when using an AESA (Active Electronically Steered Array). This paper focuses on non-rectangular arrays because the application of windowing is more complex for this type of array.