A new type of cascaded series feed beamforming networks (BFNs) is introduced. The network architecture is based on a dualseries Nolen matrix topology. It is able to produce tapered output amplitude distributions from N × N configurations. The general concept, analysis and systematic design of the BFNs are given. The networks are designed and intended to be used mainly for low Sidelobe Level (SL...

A new Fresnel Zone (FZ) Antenna to focus the microwave power in the radiation near field region is presented. FZ Antennas, in comparison with array antennas or reflector antennas, conventional focused antennas, take the advantages of design simplicity as well as lower sidelobe levels (SLL) in both axial and transverse directions. Simulation results and comparisons made between the new structure...

A new optimization algorithm—Improved Mayfly Optimization Algorithm (IMOA)—is proposed in this paper to fulfill the low sidelobe level (SLL) design requirements of spaceborne array antenna. MOA is a heuristic algorithm inspired by flying behavior and mating process mayflies. It has unique speed updating system with great convergence, strong stability, fast solution speed, high precision. Based ...

This paper proposes a Genetic Algorithm (GA)-enhanced Almost Difference Set (ADS)based methodology to design thinned linear arrays with low peak sidelobe levels (PSLs). The method allows one to overcome the limitations of the standard ADS approach in terms of flexibility and performances. The numerical validation, carried out in the far-field and for narrow-band signals, points out that with af...

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-

In this paper, we have addressed three major problems of uniform linear array in case of a sensor failure at any position. We assume that sensor position is known. The problems include increase in sidelobe levels, displacement of nulls and diminishing of null depth. The desired null depth is achieved by making the weight of symmetrical counterpart element passive. Genetic algorithm (GA) along w...

The communication distance and the energy of the nodes are limited in large-scale wireless sensor networks (WSNs). Collaborative beamforming is an effective way to solve such problem. However, the distribution of node location is not uniform, which leads to poor performance of the mainlobe and causes the high sidelobe level (SLL). This paper presents a novel collaborative communication method b...

In this paper one optimization heuristic search technique, Hybrid Evolutionary Programming (HEP) is applied to the process of synthesizing three-ring Concentric Circular Antenna Array (CCAA) focused on maximum sidelobe-level reduction. This paper assumes non-uniform excitations and uniform spacing of excitation elements in each three-ring CCAA design. Experimental results reveal that the design...

For pattern synthesis of arrays, it is required to find out appropriate weighting vectors to yield a desired radiation pattern. It is well known that several methods for above purpose are available in literature. It is an established fact that when an attempt is made to reduce the first sidelobe level, the beamwidth increases. However, it is of interest in the present work to synthesize an arra...