Studies On Decoupling And Intelligent Design Technologies For Base Station Antenna Arrays

Base station antennas,serving as the critical link between the communication system and users,facilitate data transmission between terminals through the reception and emission of signals and are crucial components of mobile communication systems.In pursuit of significant advancements in transmission rates and channel capacities,mobile communication systems have introduced substantial challenges to base station antennas,including requirements for large-scale,multi-band,and compact integration.In confined spaces with complex electromagnetic environments,traditional base station antennas face issues,including pattern distortion,port mismatch,and increased power consumption.These issues have become bottlenecks in the performance of communication systems.Therefore,a profound analysis of the physical mechanisms underlying coupling interference is crucial.Exploring novel technologies for decoupling in base station antenna arrays has become an urgent need for mobile communication systems.This dissertation integrates subwavelength structures and artificial intelligence algorithms into the design of base station antennas,conducting research on array decoupling technology at both the physical structure and optimization algorithm levels.At the level of subwavelength physical structures,the research explores decoupling technologies based on higher-order mode suppression methods,scattering reduction techniques,and spoof surface plasmon polaritons(SSPPs)structures,achieving significant improvements in array decoupling performance.At the artificial intelligence algorithm level,the research investigates in-band decoupling techniques based on forward and backward networks,and cross-band decoupling techniques based on generative adversarial networks,overcoming performance bottlenecks in artificial decoupling design.The main contents of this dissertation are summarized as follows:1.Studies on decoupling technology for shared-aperture antennas based on higherorder mode suppression method.This research addresses the issue of pattern distortion due to scattering interference among shared-aperture antennas.It proposes a decoupling technique based on the suppression of higher-order modes.Originating from characteristic mode theory,this technique attributes scattering interference to the excitation of higher-order modes.It identifies the target higher-order modes through precise analysis of the scattering field.On this basis,a shared-aperture antenna array is designed,incorporating structures that suppress higher-order modes into the design of low-band antenna.This endows the lowband antenna with electromagnetic-transparent characteristic.Both simulated and measured results show stable radiation from the antenna,achieving the decoupling effect from scattering interference,confirming the practical application value of the decoupling technique based on the suppression of higher-order modes.2.Studies on triple-band shared-aperture antenna decoupling technology based on scattering reduction method.Addressing issues such as narrow decoupling bandwidth,insufficient control precision,and low efficiency in existing scattering interference decoupling technologies,this work proposes a decoupling technique based on the scattering reduction method.This technique establishes a set of quantitative analysis and assessment models for scattering interference,introduces a scattering reduction method suitable for decoupling in base station antenna arrays,achieves precise control of electromagnetic-transparent bands,and designs a dual-band electromagnetic-transparent comb-shaped antenna.Utilizing this comb-shaped antenna,a triple-band shared-aperture antenna array is designed,demonstrating the accuracy of the scattering interference assessment model through simulated and measured results.This work achieves precise control of the decoupling characteristics and effectively broadens the decoupling bandwidth,showcasing the application value of the scattering reduction method in shared-aperture antenna design.3.Studies on triple-band shared-aperture antenna decoupling technology based on SSPPs structure.This work proposes a decoupling technique based on the SSPPs structure for addressing the common issue of port signal interference in shared-aperture antennas.This technique innovatively incorporates the tunable dispersion characteristics of SSPPs structures into shared-aperture base station antennas.By integrating transmission structures with specific cutoff frequency,it achieves an ultra-wideband decoupling effect for port signal interference.On this basis,by combining the equivalent circuit and miniaturization methods,an integrated design is proposed,realizing efficient integration of SSPPs structure and antenna.Simulation and measurement on the triple-band sharedaperture antenna array indicate that the SSPPs structure effectively enhances port isolation,achieving an ultra-wideband array decoupling effect.4.Studies on intelligent design technology for decoupling in base station antenna arrays.Addressing the several challenges encountered in interference decoupling design,such as the complexity of the decoupling structure,the massive computational demands of array optimization,and the limitations of manual design,this research has introduced artificial neural networks into the design of decoupling structures.The research proposes a in-band decoupling technique based on forward and backward neural networks and a cross-band decoupling technique based on generative adversarial networks.The forward and reverse neural networks possess excellent feature extraction and multidimensional data processing capabilities,reducing the time needed for simulation optimization.The networks quickly determine antenna parameters that meet engineering requirements.Generative adversarial networks utilize image synthesis capabilities,mapping decoupling structures and electromagnetic characteristics to visual images and their labels,intelligently designing excellent decoupling structures and overcoming the performance limitations of traditional manual designs.Through a series of model simulations and measurements,this research validates the effectiveness of these two techniques,providing new research directions for achieving leapfrog development in base station antenna performance.