Low Sidelobe Phased Array Pattern Synthesis With Compensation for Errors Due to Quantized Tapering

Recently, the iterative Fourier transform (IFT) method has been introduced for the synthesis of low sidelobe patterns for array antennas with periodic element arrangement. The IFT method makes use of the property that for an array with periodic element spacing, an inverse Fourier transform relationship exists between the array factor and the element excitations. This property is used in an iterative way to derive the array element excitations from the prescribed array factor using a direct Fourier transform. With some simple additions, the same IFT technique is also applicable to mitigate the degradation of sidelobe performance of array antenna caused by quantization of its taper across the array when using discrete control devices. Numerical examples of low sidelobe pattern synthesis applying compensation for taper quantization errors are presented. The results refer to both phase as well as amplitude tapering of linear arrays of various sizes.