Research And Design Of High Performance Broadband Dual Polarization Microstrip Patch Antenna

As an important part of the wireless communication system,the antenna directly determines the effectiveness and reliability of the communication system.Because of its advantages such as low profile,light weight and easy to conformation,microstrip antenna has become one of the hotspots in the field of wireless communication.However,the microstrip antenna has the inherent shortcomings of narrow operating frequency band.Moreover,the dual-polarization antenna can greatly improve the channel capacity of the system.In this context,this thesis focuses on the microstrip antenna bandwidth broadening technology and dual-polarization realization technology,and designs two C-band wideband dual-polarization microstrip antennas.The main research contents of this thesis are summarized as follows:Aiming at the problem of the narrow operating frequency band of a microstrip patch antenna,the method of how to widen its operating frequency band is studied.Based on this,it is planned to improve the bandwidth of the microstrip antenna by using improved L probe feed mode.Moreover,the complementary antenna structure is considered.On the one hand,the structure has two resonant frequency points to further increase the working bandwidth of the microstrip antenna;on the other hand,the structure also enhances the stability of the radiation characteristics of the microstrip antenna in its working frequency band,especially at higher working frequency.According to the overall design requirements of the C-band broadband dual-line polarized microstrip antenna,the dual-line polarized microstrip antenna design based on the four-patch complementary structure was completed.The full-wave electromagnetic simulation software Ansoft HFSS15.0 was used to model and optimize the antenna's relevant performance parameters.After optimizing the relevant antenna parameters through simulation,the antenna's dual linear polarization coincidence impedance bandwidth is 38%,that is,within 3.9GHz?5.8GHz,the antenna's standing wave ratio(VSWR)is less than 2,and the antenna also has many excellent characteristics,such as the port isolation between different polarizations is greater than 22dB,the gain is not less than 9.0dBi.In addition,the antenna has the advantage of a simple structure and can be widely used in C-band ultra-wideband wireless communication system.According to the basic requirements of the C-band broadband dual-circular polarized microstrip antenna in this thesis,the design of broadband double circular polarized microstrip antenna is based on the broadband dual polarized microstrip antenna and based on the biorthogonal L probe feed structure,and through the two diagonal strips of microstrip patch antenna corner cut processing,inspire a two along the diagonal vertical amplitude equal to each other,phase difference of 900 linear polarization component,to realize the design of the double circular polarized broadband microstrip patch antenna.After the simulation and optimization of full-wave electromagnetic simulation Ansoft HFSS15.0 software,the antenna achieves 28%coincidence operating bandwidth,that is,within the operating frequency band of 4.3GHz?5.7GHz,the antenna's standing wave ratio(VSWR)is less than 2,and its axis ratio(AR)is less than 2.The dual-circular polarization antenna is not only simple in structure,but also has wide axial ratio bandwidth and can be widely used in C-band ultra-wideband wireless communication system.