Spherical Array Antenna Beamforming Technology

In order to achieve greater aerodynamic performance and weapons performance, various kinds of advanced aircraft expect the radar units they carried to be installed on surface of the flight vehicle so that the surface of the arrays coincides with the surface of aircraft, forming conformal arrays antennas. To improve the performance of the conformal arrays, this dissertation uses the technology of antennas thinned and antennas sparse to calculate the most suitable positions where the antennas should be placed. Marshalling sparse arrays on surface of the vehicle takes full advantage of its geometric shapes, not only as far as possible big aperture, low costs and high gain arrays could be got, but also RCS of the aircraft could be reduced.This article mainly researches and discusses about the spherical arrays antennas. Unifying the conformal arrays antennas and the sparse arrays antennas' correlation technique, utilizing the optimization algorithm realizes the arrays synthesis and beam forming.The main details and important results which bring forth new ideas are listed as follow:1: Introduce the emergence and the development of genetic algorithms briefly. And compared with biological evolution in nature, genetic algorithm is explained lively and clearly. Finally, a brief description is given about the basic process of genetic algorithm and parameter settings.2: A new antenna elements distribution model is proposed, in this model the antennas could be distributed approximately uniform, which guarantees the array pattern without distortion under a large scanning.3: To suppress the peak sidelobe level, the antennas in the new model is thinned. So the number of the element required become smaller, and the production cost is reduced.4: The phase-only, the amplitude-only and the phase-amplitude pattern synthesis method are adopted to achieve conformal spherical array beamforming, with these methods we could achieve wide-angle array pattern nulling shaped in the case of interference with the direction of inaccurate.5: Propose a spherical region pre-partition method, and introduce random disturbance to the distribution of the elements, through the genetic algorithms, optimal sparse of the spherical conformal array antenna unit location is achieved in the multi-constrained.