Design Of MIMO Antenna For Mobile Terminal Based On Neutral Line Decoupling Technology

With the rapid development of communication technology,the existing 4G technology can no longer meet the current data communication requirements for mobile speed.On the basis of not expanding the bandwidth,how to increase the wireless data throughput of mobile terminals is the main topic of current research.MIMO(Multi-input-multi-output)is an important technology to fully tap spectrum resources and improve data capability.It uses multiple antennas to receive and receive wireless signals simultaneously to improve wireless data transmission rate.How to design MIMO antenna with good performance in the limited space of mobile terminal has become a topic of concern in the industry.The limited space of mobile terminals makes the mutual coupling effect between multiple MIMO antenna elements close to each other serious,and it is also an important factor affecting the antenna separation index.Neutral line decoupling technology is an effective way to improve the performance of MIMO antenna,but because the layout of neutral line often depends on experience,in order to make better use of neutral line to achieve decoupling,this paper uses characteristic mode analysis method to analyze the current distribution of antenna mode,and further guide the optimization of the design of neutral line,so as to improve the design efficiency of MIMO antenna.Meet the engineering design requirements.On the basis of introducing the principle and characteristics of MIMO antenna,the decoupling method of MIMO antenna is studied and analyzed.Two MIMO antennas with high isolation are designed.The main contents are as follows:Firstly,several decoupling technologies of MIMO antenna are analyzed and compared after modeling and Simulation of each decoupling technology.According to the actual structure characteristics of mobile terminal,the neutral line decoupling technology is an important method for MIMO antenna decoupling of mobile terminal,and its principle and characteristics are analyzed.Secondly,the design case of MIMO antenna with three neutral lines presented in the literature is analyzed in detail by using characteristic mode analysis method,and the original model is further optimized according to the conclusions of the analysis,and the MIMO antenna with good performance is obtained.Through the integration of characteristic mode analysis and neutral line design,the guiding method of neutral line application in MIMO antenna decoupling is refined.Thirdly,a WiFi MIMO antenna for laptop mobile terminals is designed and implemented by using characteristic mode analysis method and neutral line decoupling technology.The analysis and test results show that the antenna meets the requirements of Engineering design,solves the practical engineering problems,and introduces the guidance method of decoupling the MIMO antenna in front.Line validation.Fourth,summarize the main work of the paper and put forward some problems to be solved.The method of neutral line design guided by characteristic mode analysis proposed in this paper can be used for reference in MIMO antenna design of other mobile terminals.