Research And Design On Frequency Reconfigurable Antenna And Array

Frequency reconfigurable antennas will play an important role in wireless communication systems due to their abilities to dynamically change frequency characteristics.In this thesis,we mainly analyze and study the frequency reconfigurable methods of three types of antennas: slot antenna,patch antenna and pixel antenna.The main research topics of the thesis are as follows:1.According to the working conditions of the SPIN unit,a medium or metal is used instead basing on the previous research,and the equivalent models of a frequency reconfigurable slot array antenna are simulated and optimized.One equivalent antenna works in 9.8-10.2GHz(X-band)and another equivalent antenna works in 32.5-35.5GHz(Ka-band).Two samples of equivalent slot array antennas are fabricated and measured.The measured results agree with simulated results,and the rationality of the frequency reconfigurable slot array antenna design is verified.2.A frequency reconfigurable patch antenna / array is designed and fabricated based on PIN diodes.The antenna realizes frequency reconfigurability by 8 PIN diodes.When the diodes are forward biased,the antenna works as a patch antenna with an operating frequency of 3.4GHz.When the diodes are reverse biased,the antenna works as a 2×2 antenna array with an operating frequency of 12.2GHz,achieving a large span frequency reconfigurable antenna design.The reconfigurable antenna/array prototype is tested,and the test results are in good agreement with the simulation results,which verifies the rationality of the design.3.A 2×2 slot-coupled frequency reconfigurable pixel concept array antenna is designed.Firstly,the pixel antenna unit is designed based on the basic theory of the pixel antenna and the influence of the main parameters of the pixel antenna on the antenna performance is studied.Then we design a reconfigurable one point four feed network.Finally,a novel frequency reconfigurable pixel concept array antenna is completed.The antenna has two working states and the working frequencies are respectively 1.02 GHz and 1.78 GHz.