Phase Perturbation Method (PPM) is introduced as a new phase-only synthesis method to design reflectarray antennas so as their sidelobe level is reduced. In this method, only the reflected phase of conventional unit cells are perturbed from their required values. To this end, two approaches namely the conventional Optimization method and newly introduced Phase to Amplitude Approximation (PAA) m...

Results of an exhaustive search for minimum peak sidelobe level binary sequences are presented. Several techniques for efficiency implementation of search algorithm are described. A table of number of non-equivalent optimal binary sequences with minimum peak sidelobe (MPS) level up to length 68 is given. This number can be used in prediction of the longest length for a given sidelobe level of b...

This paper presents a new pattern synthesis algorithm for arbitrary arrays based on adaptive array theory. With this algorithm, the designer can efficiently control both mainlobe shaping and sidelobe levels. The element weights optimize a weighted L2 norm between desired and achieved patterns. The values of the weighting function in the L2 norm, interpreted as imaginary jammers as in Olen and C...

The pattern synthesis for large antenna arrays has drawn significant attention because of its wide applications. This paper introduces a hybrid approach for the fast pencil beam pattern synthesis of the large non-uniform linear or planar array, which can significantly reduce the computational cost, the number of antenna in the array, the minimum sidelobe level and the null control. The proposed...

Concentric circular arrays are increasingly shown more interest in antenna design for generating low sidelobe patterns as they have radial symmetry and an invariant beam in the azimuthal plane. Such patterns are desirable in low EMI applications. In the present work, an attempt is made to generate low sidelobe patterns from concentric circular arrays by optimizing both ring radii and individual...

This paper presents a significant sidelobe reduction if nonuniform elevational spacing of antenna elements on the sphere is used. Antenna elements are progressively phased with a uniform amplitude excitation. The calculation of the required element position is presented. The achieved sidelobe level reduction with unequally spaced arrays could reach even more than 20dB difference with regard to ...

A trinary-phased array, in which a phase quantization unit of phase shifters is 120 degrees is examined. The phase quantization unit of 120 degrees is the roughest value in practical phased array applications. Despite its rough phase quantization, the sidelobe level of less than −9 dB is attained by a genetic algorithm approach. key words: phased array, trinary phase shifter sidelobe reduc-

For phased and adaptive arrays of antennas, an optimal arrangement of antenna elements is essential to avoid grating lobes in the visible angular region of the array. Large sidelobes cause degradation in signal-to-noise ratio; grating lobes, in the worst case, cause malfunctions. One method of evaluating sidelobe level is square integration. For a given set element positions, evaluation by squa...

Low sidelobe slotted waveguide antenna is developed in the millimeter-wave band. Millimeter-wave technologies are expected to apply to automotive radars and high-bit-rate mobile communication systems because high gain and narrow beam-width is possible even though the physical size of the antenna aperture is small. Waveguide antenna is advantageous for high gain applications since the feeding lo...

Theory for random arrays predicts a mean sidelobe level given by the inverse of the number of elements. In this paper two optimization methods for thinned arrays are given: one is for optimizing the weights of each element, and the other one optimizes both the layout and the weights. The weight optimization algorithm is based on linear programming and minimizes the peak sidelobe level for a giv...