Multi-antenna Design Based On The Characteristic Modes Analysis

The renewal of information technology plays a decisive role in the development of society and the progress of mankind.The rapid development of mobile communication technology,and the antenna as the front end of the communication system to transmit and receive signals,bears the brunt of the need to adapt to the needs of the market,the need to achieve the miniaturization of the antenna,broadband and integration.This paper takes the integration of multiple communication antennas as its application background.Based on the previous experience in designing MIMO antennas,Wi Fi antennas and Bluetooth antennas,and based on the research of the characteristic modes analysis method used to design antennas,this article designed a multi-antenna that consists of three antennas that can cover the mobile communications band,the Wi Fi 2.4GHz and 5.8GHz bands,and the Bluetooth band,respectively.The mobile communication antenna uses a coupled broadband monopole antenna as a unit to form a four-element MIMO antenna.The characteristic modes analysis results are used to slot the appropriate location on the large floor to reduce the correlation coefficient between the antenna elements,so that each antenna can provide Independent channel;Wi Fi dual-band dual-polarized antenna uses the Babinet principle to design a square-ring slot resonant antenna as an array element to form an equal-amplitude in-phase feed binary array to increase the antenna gain,and orthogonally excite two modes to achieve bipolarity.Dual-polarized port isolation is improved by adjusting feed lines and adding neutralization lines.Two antennas of similar structure cover two Wi Fi bands.The Bluetooth antenna uses the mobile communication antenna floor as a radiator after analyzed the characteristic modes of the floor.Choosing the right feed position excite it so that the antenna operates in the Bluetooth band.In order to verify the correctness of the antenna design and simulation,we have processed,manufactured and tested the physical object of the antenna.The test results are in good agreement with the simulation results.The indicators of the antenna can meet the design requirements.The completion of this work shows that the characteristic modes analysis method has considerable significance for the design and optimization of antennas with complex structures such as multiple antennas.