Study On Techniques Of Miniaturized Broadband Antenna And Array For Next Generation Of Wireless Communication

With the rapid development of modern wireless communication technologies, the increasing miniaturization and highly integration become the main development directions of communication systems, and as the key front-end component of communication equipments, antenna's performance plays a crucial role on the communication quality. Therefore, the research of antennas as mobile terminals has become an important direction and received wide attention, and the research focused on miniaturization, broadband, multi-band and so on. Meanwhile, with the commercialization of the upcoming third-generation mobile communication systems and the study of the fourth-generation mobile communication systems, in order to improve the channel capacity, transmission rate and communication quality, wireless physical layer architecture of MIMO (Multiple Input Multiple Output) multi-antenna array is becoming a key technology without doubt.In this thesis, we summary and study the technologies and methods for antennas to realize miniaturization and broadband as mobile terminals, and combine multiple technologies together organically to design a new, practical and easily-made antenna structure with multi-ports.The main content of this thesis are as follows. Firstly, we analyze the antenna's basic operation mechanism, performance parameters and design requirements when applied to wireless systems, for example, MIMO antenna system; and study the methods of angle measurement with mono-pulse and the theory of received beams using sum and difference of phase with mono-pulse which are widely used in phased array radar antenna, and point out the possibility to use these technical approach for the realization of new type miniaturized broadband antenna.Secondly, we combine the theory and technology mentioned above and the methods used to realized miniaturization and wide band together, and design an antenna model with unique structure and excellent performance, specifically including the proposition of the design idea to bind the four-port antenna and the antenna with main and feed radiation elements together, and as a basis of this idea, we design a broadband, small four-port antenna with relative bandwidth of 57% and size of 0.7λ×0.7λ×0.2λ, then verify the rationality and feasibility of this theoretical research work through simulation analysis and testing.Finally, based on the broadband, small four-port antenna mentioned above, we add some techniques of array antenna in after further study to complete the design of TD-SCDMA dual-polarized small antenna array for base station, and have a detailed analysis of the array antenna which is in the±45°dual polarization mode using four steps, then demonstrate the rationality and feasibility of the array antenna design through simulation.The technical methods and research ideas in this thesis lay a foundation for the practical engineering application of the antenna in next steps and further improvement of the antenna performance.