Research On Array Element And Sub-array Level Multi-beam Forming Method

One of the research hotspots in modern radar array signal processing and wireless communication is digital multi-beam forming technology,which can simultaneously form multiple beams with various directions based on a single antenna aperture.Each beam can satisfy various performance requirements,enable radar,communication,and other electronic systems to work at a much higher data rate and efficiency.Large-scale arrays can satisfy needs including radar long-range missions,but the large number of arrays connected to digital transceiver components on each array element will increase the cost of hardware and the computational burden on software.An approach to reduce the number of digital channels required is by using the weighting at the sub-array level and connect it with an adaptive approach to form multiple beams.This paper investigated the multi-beam forming method including the combined adaptive and intelligence algorithm sub-array division scheme.The following three sections can be used to summarize the content:1.Array signal model and beamforming algorithm.The basic model of the antenna array signal is provided,and the fundamentals of beamforming and multi-beamforming.Experimental simulation is used to compare the performance of beamforming based on various window functions in the data-independent method.Beamformers are studied and analyzed using various robust adaptive criteria,and extensive performance compared.A sub-array-level dimensionality reduction adaptive array model based on the sub-array transformation matrix method is also provided,which provides as the foundation for large-scale array sub-array-level beamforming.2.Algorithm for multi-beam forming at array level.By matching multiple sets of weighting vectors to each array element,the digital matching method can form multiple beams at the same time.The method can effectively control the main and side lobe performance of the beam when combined with window functions,according to the experimental simulation,but a large number of digital channels will result in a large number of digital channels.The implementation system is complex,which adds to the computational and costs involved.The IFFT-based beamforming approach utilizes the corresponding relation in the time-space domain to form multiple beams,reducing complexity of the algorithm and calculation time.However,the direction of the main lobe for forming multiple beams is fixed,which limits practical applications.The multi-beam formed based on adaptive criteria has stronger robustness.The performance of multi-beam formed under various adaptive criteria and the relationship between them are analyzed through experimental simulation.3.Sub-array level multibeam forming algorithm.Aiming at the problem of sub-array structure design,the multi-beam forming under the uniformly adjacent sub-array structure is introduced.The simulation results show that phase control must be performed at the array element level The desired multibeam could be obtained by matching the appropriate weights,and the digital beamforming can reduce the hardware complexity and make the overall system easy to control.By weighting the sum beam at the array level and weighting multiple difference beams at the sub-array level,digital beamforming enables for independent optimization of the sum and difference beams,and even the formation of the desired multibeam.Finally,based on the optimal sub-array division scheme combined with the adaptive criterion for multibeam formation,the sub-array division of large arrays based on ant colony optimization,particle swarm optimization,and genetic algorithm in population intelligence optimization algorithm is proposed,and simulations are performed for adaptive multibeam formation at the sub-array level for linear and planar arrays,respectively,with performance comparison and analysis.